Method of making fibrous material

[0001] This invention relates to methods of making fibrous materials.

BACKGROUND ART [0002] Fibrous materials, for example cellulosic and lignocellulosic materials, are made, processed and used in large quantities in a number of applications. Often, such fibrous materials are used once and then disposed of as waste.

[0003] US 4244847 describes a method of producing: (1) generally dry fiber blend; (2) powdered elastomer / fiber composite masterbatch or completely mixed material; or (3) elastomer / fiber composite masterbatch or completely mixed material.

[0004] EP 0801168 A1 discloses a method and apparatus for collecting individually layers from a laminated coating comprising a plurality of layers made of different materials by peeling or separating these layers from each other.

[0005] GB 1 503 103 discloses a method of removing a foreign material coating from the surface of a plastic material.

SUMMARY [0006] The invention relates to the subject matter of claims 1 to 12.

[0007] Methods for producing fibrous materials are disclosed that include shearing a fiber source to provide a first fibrous material and passing the first fibrous material through a first screen having an average mesh size of 1.59 mm or less (1/16 inch, 0.0625 inch) to provide a second fibrous material.

[0008] In some embodiments, the average mesh size of the first screen is less than about 0.79 mm (1/32 inch, 0.03125 inch), e.g., less than about 0.40 mm (1/64 inch, 0.015625 inch), less than about 0.20 mm (1/128 inch, 0.0078125 inch) or even less than about 0.10 mm (1/256 inch, 0.00390625 inch).

[0009] In specific embodiments, shear is carried out by means of a slicer with rotary knives. [0010] The second fibrous material can be collected, for example, in a container having a pressure below nominal atmospheric pressure, for example, at least 10 percent below nominal atmospheric pressure or at least 75 percent below nominal atmospheric pressure.

[0011] The second fibrous material may, for example, be cut once or many times, for example, twice, three times or even more, for example ten times.

[0012] The second fibrous material may, for example, be cut and the resulting fibrous material passed through a first screen.

[0013] The second fibrous material can be cut and the resulting fibrous material passed through a second screen having an average mesh size smaller than the first screen to obtain a third fibrous material.

[0014] The ratio of the average length to diameter ratio of the second fibrous material to the average ratio of length to diameter of the third fibrous material may be, for example, below about 1.5, below about 1.4, below about 1.25, or even below about 1, 1.

[0015] The second fibrous material may, for example, be passed through a second screen having an average mesh size smaller than the first screen.

[0016] This shearing and passing can, for example, be carried out in parallel.

[0017] The second fibrous material may have an average length to diameter ratio, for example, greater than about 10/1, greater than about 25/1, or even greater than about 50/1.

[0018] The average length of the second fibrous material may be, for example, in the range of from about 0.5 mm to about 2.5 mm, for example, in the range of from about 0.75 mm to about 1.0 mm. The average width of the second fibrous material may be, for example, in the range of from about 5 μm to about 50 μm, for example, in the range of from about 10 μm to about 30 μm.

[0019] The standard deviation of the length of the second fibrous material may be less than about 60 percent of the average length of the second fibrous material, for example, less than about 50 percent of the average length of the second fibrous material.

[0020] In some embodiments, the BET surface area of ​​the second fibrous material is greater than

2 2 about 0.5 m²/ g, for example, greater than about 1.0 m²/ g, greater than about 1.5 m²/ g, greater than about 1.75 m²/ g or even greater than about 0.5 m²/ G.

[0021] In some embodiments, the porosity of the second fibrous material is greater than about 70 percent, for example, greater than about 85 percent or greater than about 90 percent.

[0022] In some embodiments, the ratio of the average length to diameter ratio of the first fibrous material to the average length to diameter ratio of the second fibrous material is below about 1.5, for example, below about 1.4, below about 1.25, or below about 1 1.

[0023] In specific embodiments, the screen is made by interleaving the monofilaments.

[0024] The fiber source may include, for example, cellulosic material, lignocellulosic material. The fiber source may be, for example, sawdust.

In some embodiments, the fiber source comprises a blend of fibers, e.g., fibers derived from a paper source and fibers derived from a textile material source, e.g., cotton.

[0026] Fibrous materials that have an average length to diameter ratio greater than about 5, and having a standard deviation of fiber length less than about sixty percent of the average fiber length can be produced.

[0027] For example, the average length to diameter ratio may be greater than about 10/1, for example, greater than about 15/1, greater than about 25/1, greater than about 35/1, greater than about 45/1 or even can be greater than about 50/1.

[0028] For example, the average length may range from about 0.5 mm to about 2.5 mm.

[0029] Composites are disclosed that include fibrous material made according to the invention, a resin and a dye. The dye may, for example, assist in masking fibrous material in the composite.

[0030] For example, the fibrous material may have an average length to diameter ratio above about 5, and a standard deviation of the fiber length below about sixty percent of the average fiber length. [0031] In some embodiments, the composite additionally comprises a pigment.

[0032] In some embodiments, the fibers are soaked or on a dye. [0033] Composites may include a fragrance or flavoring.

[0034] Also disclosed are methods for making composites that include dyeing fibrous material, combining fibrous material with resin, and making composites from this combination.

[0035] Methods for making composites are disclosed that include adding a dye to a resin to provide a dye / resin combination, combining a dye / resin combination with a fibrous material, and making a composite from a dye / resin combination and a fibrous material.

[0036] Each composite may be in the form of, for example, a platform, pipes, panels, boarding materials, boards, fasteners, sheets, blocks, bricks, columns, fences, elements, doors, shutters, awnings, curtains, signs, frames , window bands, boards, materials for building floors, tiles, railway sleepers, cuvettes, tool holders, partitions, foil, wrapping foil, tapes, boxes, baskets, shelves, covers, binders, separators (partition walls), walls, mats , frames, book shelves, sculptures, chairs, tables, desks, toys, games, pallets, marinas, moles, boats, masts, fermentation chambers for sewage, car panels, computer cases, above and below covers of electrical installations, furniture, garden tables, benches, gazebos, trays , hangers, dough blades, cases, book covers, walking sticks and rehabilitation balls.

[0037] The first aspect and / or embodiments of the first aspect may have each of the following advantages or combinations thereof. Fibrous materials are easy to disperse, for example, in molten thermoplastic resin. The fibrous materials may have, for example, a relatively narrow length distribution and / or length to diameter ratio, so that their properties are clearly defined. For example, when mixed with the molten resin, the fibers of the fibrous materials can change the rheology of the molten resin in a consistent and predictable manner, resulting in resin / fibrous material combinations that are, for example, easier to form and extrude. For example, fibrous materials can easily pass through small holes or channels, such as those in or associated with injection molds, for example injection holes or hot channels. Parts made of such fibrous materials may have a good surface finish, for example, with several visible speckles of large particles and / or agglomerated particles, if desired.

[0038] In general, the comparative aspect includes concentrated fibrous materials, methods for making concentrated fibrous materials, and composites made from concentrated fibrous materials.

[0039] Methods of thickening fibrous materials are disclosed, which include adding to the fibrous material a water-soluble binder, a water-swellable binder and / or a binder having a glass transition temperature below about 25 ° C to produce a fibrous material-binder combination. The fibrous material-binder combination is compacted to produce a densified fibrous material having a bulk density that is at least about two times greater than the bulk density of the fibrous material, for example, three times, four times, five times, six times, eight times, ten times, twelve times, twenty times or more, for example forty times. Preferably, the bulk density of the compacted material is at least about three times or about four times greater than the bulk density of the fibrous material.

[0040] Also disclosed are methods for densifying fibrous materials that include densifying fibrous material derived at least in part from polymer-coated paper to produce a densified fibrous material having a bulk density that is at least about twice the bulk density of the fibrous material, for example three times, four times, five times, six times, eight times, ten times, twelve times, twenty times or more, e.g

EP 1 877 192 B9 forty times greater. Compaction involves heating the fibrous material to a temperature of at least about 50 ° C.

[0041] The disclosed methods for densifying fibrous materials include moving the fibrous material through a binder application area in which a binder is applied to form a fibrous material-binder combination. The fibrous material-binder combination is compacted to produce a concentrated fibrous material having a bulk density of at least about twice as much as the bulk density of the fibrous material, e.g., three times, four times, five times, six times, eight times, ten times, twelve times, twenty times or more, for example forty times more.

[0042] Also disclosed are methods for densifying fibrous materials that include removing air from the fibrous material to at least approximately double the bulk density of the fibrous material. For example, the method may include sealing the fibrous material in the container and removing air from the container.

[0043] Granules or pellets are disclosed which include compacted fibrous material. Granules or lumps₃ have a bulk density of at least 0.3 g / cm³. The concentrated fibrous material includes cellulosic or lignocellulosic material, a water-soluble binder, a water-swellable binder, and / or binders having a glass transition temperature below about 25 ° C. The granules or pellets have, for example, an average thickness in the range of about 2 mm to about 20 mm, an average width in the range of about 2 mm to about 40 mm, and an average length in the range of about 5 mm to about 40 mm. In some embodiments, the granule means a structure with a hollow inner portion or multi-flap structure.

[0044] Plate-like densified fibrous materials are disclosed which have a bulk density of co ₃ at least 0.3 g / cm³. The densified fibrous materials include cellulosic or lignocellulosic material. Plate-like densified fibrous materials have, for example, an average thickness in the range of about 2 mm to about 20 mm, an average width in the range of about 2 mm to about 40 mm, and an average length in the range of about 5 mm to about 40 mm.

[0045] Methods for thickening fibrous materials are also disclosed, which include adding to the fibrous material a water-soluble binder, a water-swellable binder and / or binders having a glass transition temperature below about 25 ° C to produce a fibrous material-binder combination . The fibrous material-binder combination comprises less than about 25 weight percent binder, for example, 15 weight percent, 10 weight percent, 5 weight percent, or less than about 1 weight percent. The fibrous material-binder combination is compacted to produce a concentrated fibrous material having a bulk density that is at least about two times greater than the bulk density of the fibrous material, e.g., three times, four times, five times, six times, eight times, ten times, twelve times, twenty times or more, for example, about forty times greater.

[0046] Methods of pressing fibrous materials are disclosed, which include placing the fibrous material containing the binder in a certain position relative to the element, for example between the first and second elements, to provide an unpressed composite, and compressing the unpressed composite to produce a pressed composite.

[0047] In some embodiments, the compression is carried out using a single element and a substrate.

[0048] Any densified fibrous material can be used to make any article disclosed herein.

EP 1 877 192 B9 [0049] The densified fibrous materials may contain a fragrance or flavor.

[0050] The densified fibrous materials can be used, for example, for the production of composites, or they can be used alone or together with additives, for example, as sustained release matrices.

[0051] Also disclosed are methods for densifying fibrous materials, for example cellulosic or lignocellulosic material, in which a binder is not used.

[0052] Granules or lumps of compacted fibrous material are disclosed which have a bulk density of ₃ at least about 0.3 g / cm³. The densified fibrous materials include a fibrous material other than cellulosic or lignocellulosic material and a binder. The granules or pellets have an average thickness in the range of about 2 mm to about 20 mm, an average width in the range of about 2 mm to about 40 mm and an average length in the range of about 5 mm to about 40 mm.

[0053] Plate-like densified fibrous materials are disclosed which have a bulk density of co ₃ at least about 0.3 g / cm³. The densified fibrous materials include fibrous material, other cellulosic or lignocellulosic material and a binder. Plate-like densified fibrous materials have an average thickness in the range of about 2 mm to about 20 mm, an average width in the range of about 2 mm to about 40 mm, and an average length in the range of about 5 mm to about 40 mm.

[0054] The second aspect and / or embodiments of the second aspect may have each of the following advantages or combinations thereof. The densified fibrous materials, e.g. in the form of granules or lumps, are easier to handle, feed to machines, transport and mix with other materials, e.g. resins, e.g. thermoplastic resin.

[0055] Generally, the comparative aspect includes cross-linked composites and composites that contain fillers on a nanometric scale. Composites, which include fillers on a nanometric scale, are optionally crosslinked when desired.

[0056] Methods for making composites are disclosed that include combining a fibrous material with a radiation curable resin, for example a thermoplastic resin, to form a fibrous material / curable resin combination. The fibrous material has an average length to diameter ratio above about 5, and the standard deviation of the fiber length is below about eighty-five percent of the average fiber length. The fibrous material / curable resin is irradiated, for example with ionizing radiation, to at least partially crosslink the curable resin. In some embodiments, the desired shape is formed before the irradiation step from the fibrous material / curable resin combination.

[0057] The radiation curable resin may be, for example, a thermoplastic or thermosetting resin, for example, a thermosetting casting resin. For example, the radiation curable resin may be a polyolefin, e.g. polyethylene (e.g., polyethylene copolymer), polypropylene (e.g., polypropylene copolymer), polyester (e.g., polyethylene terephthalate), polyamide (e.g., nylon 6, 6/12 or 6/10), polyethyleneimine, elastomeric styrene copolymers (e.g. styrene-ethylene, butylene-styrene copolymers), polyamide elastomer (e.g. polyether-polyamide copolymer), ethylene-vinyl acetate copolymer or compatible mixtures of these resins.

[0058] In certain specific embodiments, the resin is a polyolefin that has a polydispersity above about 2, e.g., above about 3, above about 3.5, above about 4.0, above about 4.5, above about 5.0, above about 7.5 or even above about 10. High polydispersity can improve the impact resistance of the cured composite. In some embodiments, the polyolefin has a flow rate above about 10, for example above 15, above 20, above 25, above 30, or even above about 50.

EP 1 877 192 B9

The high flow rate can facilitate the production of the composite, for example, by reducing the shear heat during the production of the composite.

[0059] In specific embodiments, the fibrous material is provided by shearing a fiber source, for example sawdust, formed when sawing deciduous or coniferous wood (for example oak, cedar or redwood).

[0060] The average ratio of fiber length to fiber diameter can be, for example, above about 10/1, e.g. above 15/1, above 25/1 or even above about 50/1. A high L / D value can improve mechanical properties, e.g. tensile strength and flexural modulus. In some embodiments, the standard deviation of the fiber length is less than about seventy-five percent of the average fiber length, e.g., less than fifty percent, less than 35 percent, less than 25 percent, less than 15 percent, less than 10 percent, less than 5 percent, or even less than about 2.5 percent. A small standard deviation can, for example, improve the processability of the fibrous material / resin mixture. The average length of fibrous material may, for example, be in the range of from about 0.5 mm to about 2.5 mm, for example in the range of from about 0.75 mm to about 1.0 mm. The average width of the fibrous material is in the range from about 5 μm to about 50 μm, for example in the range from about 10 μm to about 30 μm.

[0061] The fibrous material may, for example, come from a textile material, for example, cuttings or cotton debris, a paper source, a plant or a tree. In some embodiments, the fibrous material comprises a blend of fibers, e.g., fibers derived from a paper source, and fibers derived from a textile source, e.g., cotton.

[0062] In specific embodiments, the irradiation of the fibrous material / curable resin combination is performed by gamma rays or an electron beam.

[0063] In some embodiments, the composite is in the form of structure, articles and decorative articles, platforms, pipes, panels, boarding materials, boards, fasteners, sheets, blocks, bricks, columns, fences, elements, doors, shutters, awnings, curtains , signs, frames, window bands, boards, materials for building floors, tiles, railway sleepers, cuvettes, tool holders, partitions, foil, wrapping foil, tapes, boxes, baskets, shelves, covers, binders, spacers (partition walls) . walls, mats, frames, book shelves, sculptures, chairs, tables, desks, toys, games, pallets, marinas, moles, boats, masts, fermentation chambers for sewage, car panels, computer cases, above and underground covers of electrical installations , furniture, garden tables, benches, gazebos, trays, hangers, dough blades, boxes, book covers, walking sticks and rehabilitation balls.

[0064] The fibrous material is made by shearing the fiber source to provide the first fibrous material and passing the first fibrous material through a first screen having an average mesh size of about 1.59 mm or less (1/16 inch, 0.0625 inch) to provide second material. In some embodiments, the average mesh size of the first screen is less than 0.79 mm (1/32 inch, 0.03125 inch), e.g., less than about 0.40 mm (1/64 inch, 0.015625 inch).

[0065] In some embodiments, the irradiation is carried out by means of electro radiation₂ magnetic, which has energy per photon (in electron volts) above about 10² eV / photon, e.g. above 10³, 10⁴, 10⁵, 10⁶ or even above about 10⁷ eV / photon. In some embodiments, electromagnetic radiation has energy per photon in the range of about 10⁴ up to about 10⁷, for example in the range of about 10⁵ up to about 10⁶ eV / photon.

[0066] In some embodiments, the irradiation is carried out by means of electromagnetic radiation which has a frequency above about 10¹⁶ Hz, above about 10¹⁷ Hz, 10¹⁸,10¹⁹,10²⁰ or even above about 10²¹ H. In some embodiments, electromagnetic radiation has a frequency of 1 ft 99 1Q 91 in the range of about 10¹⁸ up to about 10²², for example, in the range of about 10¹⁹ up to about 10²¹ H.

[0067] In some embodiments, the irradiation is performed until the fibrous material / curable resin combination has received a dose of at least about 0.25 Mrad, for example at least 1.0 Mrad, at least 2.5 Mrad, at least 5.0 Mrad or at least about 10 Mrad. In some embodiments, the irradiation is performed until the fibrous material / curable resin combination receives a dose in the range of from about 1.0 Mrad to about 6.0 Mrad, for example in the range of from about 1.5 Mrad to about 4.0 Mrad. [0068] In some embodiments, the irradiation is carried out at a dose rate in the range of from about 5 to about 1500 kilorades / h, for example in the range of from about 10 to about 750 kilorades / h or in the range from about 50 to about 350 kilorades / h.

[0069] In some embodiments, the irradiation is carried out by means of electromagnetic radiation generated from the source ⁶⁰What.

[0070] Composites are disclosed that include hardened resin and fibrous material having an average length to diameter ratio greater than about 5, and a standard deviation of the fiber length is less than about eighty-five percent of the average fiber length.

[0071] In some embodiments, the average length to diameter ratio is above about 10/1, for example above about 15/1, above about 25/1, or even above about 50/1.

[0072] In some embodiments, the standard deviation of the fiber length is less than about seventy-five percent of the average fiber length, e.g., less than fifty percent, less than 35 percent, less than 25 percent, less than 15 percent, less than 10 percent, less than 5 percent or even below about 2.5 percent. In some embodiments, the average length of fibrous material is in the range of from about 5 mm to about 2.5 mm, for example, in the range of from about 5 μm to about 50 μm.

[0073] Also disclosed are Comparative Methods for Making Composites which include shearing a fiber source to provide a fibrous material, combining the fibrous material with a curable resin to provide a fibrous material / resin combination, and gamma irradiation to at least partially crosslink the curable resin .

[0074] In some embodiments, shear is carried out by means of a rotary cutter. [0075] Methods for making composites are disclosed that include combining a fibrous material with a radiation curable resin to provide a fibrous material / curable resin combination. The fibrous material has an average length to diameter ratio above about 5, and the standard deviation of the fiber length is less than about eighty-five percent of the average fiber length. The desired shape and irradiation is formed from the fiber material / curable resin to at least partially crosslink the curable resin.

[0076] Methods for making composites are disclosed that include combining a filler, for example a fibrous material, with a radiation curable resin to produce a filler / curable resin combination and irradiation of a filler / curable resin combination to at least partially crosslink the curable resin.

[0077] Methods are disclosed for reducing the growth of microorganisms, e.g. yeast and / or bacteria, in composites that include irradiating the composite with ionizing radiation prior to

EP 1 877 192 B9 use. In some embodiments, the composite is in the form of a board, e.g., boarding material.

[0078] Composites are disclosed that include a resin, a filler having a lateral dimension below about 1000 nm, and a fibrous material. In some embodiments, the transverse dimension is less than 500 nm. [0079] In some embodiments, the resin is crosslinked, for example, using a chemical crosslinker or radiation.

[0080] In some embodiments, the fibrous material includes cellulosic or lignocellulosic material. [0081] In specific embodiments, the fibrous material has an average length to diameter ratio greater than about 5, and a standard deviation of the fiber length is less than about eighty-five percent of the average fiber length.

[0082] Methods for making composites are disclosed that include combining a filler having a transverse dimension below about 1000 nm and a fibrous material with a resin. These methods may further include giving the desired shape to the filler / fibrous material / resin combination. The desired shape can, for example, be irradiated to at least partially crosslink the resin.

[0083] Methods for making composites are disclosed that comprise combining a filler having a lateral dimension below about 1000 nm and a fibrous material with a radiation curable resin to provide a filler / fibrous material / curable resin combination and irradiation of the filler / fibrous material / curable resin combination to least partial crosslinking of the curable resin.

[0084] Composites are also disclosed which include resin and sawdust containing fibers having an average length to diameter ratio greater than about 5, and a standard deviation of the fiber length is less than about eighty-five percent of the average length of the fiber dispersed therein. In some embodiments, the sawdust is derived from deciduous wood, e.g. oak, or coniferous wood, e.g. cedar, redwood or pine.

[0085] Also disclosed are methods for making composites that include cutting sawdust to provide a fibrous material and combining the fibrous material with a resin to provide a fibrous material / resin combination. In some embodiments, the methods may further include irradiating the fibrous material / resin combination with gamma radiation to at least partially cure the resin.

[0086] The comparative aspect and / or embodiments of the comparative aspect may have each of the following advantages or combinations thereof. Composites can have excellent mechanical properties, e.g. abrasion resistance, compressive strength, fracture toughness, impact strength, bending strength, tensile modulus, bending modulus and elongation at break. Composites can have excellent performance at low temperatures, e.g. reduced tendency to break and / or crack at low temperatures, e.g. below 0 ° C, e.g. below -10 ° C, -20 ° C, -40 ° C, - 50 ° C, -60 ° C or even below -100 ° C. In addition, the composites can have excellent performance at high temperatures, e.g. maintain their favorable mechanical properties at a relatively high temperature, e.g. at temperatures above 100 ° C, e.g. above 125 ° C, 150 ° C, 200 ° C, 250 ° C , 300 ° C, 400 ° C or even above 500 ° C. Composites may have excellent chemical resistance, e.g., solvent swelling resistance, e.g. hydrocarbon solvent, resistance to harmful chemical effects, e.g. strong acids, strong bases, strong oxidants (e.g. chlorine or bleach) or reducing agents (for

EP 1 877 192 B9 example of active metals such as sodium and potassium). Composites may have a reduced tendency to rot and decompose because the treatment of composites by radiation can kill all microorganisms, for example fungi, bacteria, or insects.

[0087] Generally, the comparative aspect presents fragrance-containing composites and methods of making them. Fragrance-containing composites can be crosslinked if desired.

[0088] Fiber sources, fibrous materials or concentrated fibrous materials in combination with a fragrance are disclosed. Examples of fragrances include those of cedar, evergreen or redwood. In some embodiments, the fiber source, fibrous material or concentrated fibrous material in combination with the fragrance includes a dye and / or biocide. In some embodiments, the fragrance includes a woody fragrance, e.g., a natural redwood fragrance, and the color, e.g., red, corresponds to the tree from which the fragrance originates.

[0089] Fiber sources, fibrous materials or densified fibrous materials in combination with a fragrance and resin, for example, a thermoplastic resin, are also disclosed. Some embodiments also use a dye and / or biocide. In some embodiments, the fragrance includes a woody fragrance, e.g., a natural redwood fragrance, and the color, e.g., red, corresponds to the tree from which the fragrance originates.

[0090] Methods for making composites are disclosed that include adding a fragrance to the fibrous material to provide a fibrous material-fragrance combination and compressing the fibrous material-fragrance combination to form a composite. The fragrance may be present, for example, in a resin that is added to the fibrous material.

[0091] Composites that include fibrous material and fragrance are also disclosed. In some embodiments, the composites also include a resin, for example, a thermoplastic or thermosetting resin. The fibers of the fibrous material may have a length to diameter ratio, e.g., above about 5, e.g. above 10, above 25, above 50 or above about 100.

[0092] The comparative aspect and / or embodiments of the comparative aspect may have each of the following advantages or combinations thereof. Disclosed pleasant odor composites, for example densified fibrous materials and wood substitute composites, may arouse interest in purchasers and may provide remarkable branding and marketing opportunities.

[0093] Composites are disclosed that include resin and fibrous material and which have an outer surface. Part of the fibrous material is visible.

[0094] The fibrous material may be visible on the outer surface, in the outer surface or under the outer surface, for example below this surface less than about 2.54 mm (0.100 inch), for example less than 1.27 mm (0.050 inch), below 0.635 mm (0.025 inches), less than 0.254 mm (0.010 inches) or less than about 0.127 mm (0.005 inches).

[0095] Composites that include a transparent resin, for example transparent nylon or clear polypropylene, and a fibrous material are also disclosed.

[0096] Also disclosed are methods for making composites that include combining resin and fibrous material to provide a resin / fibrous material combination, and compressing the resin / fibrous material combination to form a composite having an outer surface in which part of the fibrous material is visible.

EP 1 877 192 B9 [0097] Methods for making composites are disclosed that include combining a transparent resin and fibrous material to provide a transparent resin / fibrous material combination, and compressing a transparent resin / fibrous material combination to form a composite.

[0098] The comparative aspect and / or embodiments of the comparative aspect may have each of the following advantages or combinations thereof. Composites can have unique, pleasant or even striking visual features and at the same time have the desired mechanical properties, for example, high abrasion resistance, high compressive strength, crack resistance, high impact strength, high flexural strength, high tensile modulus, high modulus of elasticity at bending and high elongation at break. Such composites can, for example, improve brand recognition and brand loyalty.

[0099] The term "fibrous material" as used herein means a material that includes a plurality of loose, discontinuous and separable fibers. For example, the fibrous material can be made from a source of a polymer coated paper or bleached kraft paper by shearing, for example with a rotary cutter.

[0100] The term "screen" as used herein means an element that allows screening of material by size, for example a perforated plate, cylinder or the like, or a wire mesh or fabric.

[0101] The nanometer scale filler is a filler that has a lateral dimension below about 1000 nm. The transverse dimension of a filler on a nanometric scale is its diameter, if it is a spherical particle or a relatively long, thin fiber, or the maximum size of an irregularly shaped particle.

[0102] Fibrous material is visible on or in the composite if a person with average vision can see it in daylight from a distance of three feet.

[0103] Other features and advantages of the invention will be apparent from the following detailed description and from the claims.

DESCRIPTION OF THE DRAWINGS [0104]

Fig. 1 is a block diagram illustrating the conversion of a fiber source into a first and second fibrous material.

Fig. 2 shows a cross-section of a slicer with rotary knives.

Figures 3-8 show a top view of various screens made from monofilaments.

Fig. 9 is a block diagram illustrating the conversion of a fiber source into a first, second and third fibrous material.

Figures 10A and 10B are photographs of a fiber source; Fig. 10A is a photograph of a container of polymer-coated paper, and Fig. 10B is a photograph of reams of unbleached kraft paper.

Figures 11 and 12 are micrographs of a scanning electron microscope of fibrous material made of polymer-coated paper at 25x magnification and 1000x magnification, respectively. The fibrous material was made using a rotary cutter, using a screen with 3.175 mm (1/8 inch) holes.

Figures 13 and 14 are micrographs of a scanning electron microscope of fibrous material made from bleached cardboard at 25x magnification and 1000x magnification, respectively. Material

EP 1 877 192 B9 fibrous was produced using a rotary cutter using a screen with 3.175 mm (1/8 inch) holes.

Figs. 15 and 16 are micrographs of a scanning electron microscope of fibrous material made from bleached cardboard at 25x magnification and 1000x magnification, respectively. The fibrous material was sheared twice with a rotary cutter using a screen with 1.59 mm (1/16 inch) holes during the first and second time shearing.

Figs. 17 and 18 are micrographs of a scanning electron microscope of fibrous material made of bleached cardboard at a magnification of 25x and a magnification of 1000x, respectively. The fibrous material was sheared three times with a rotary cutter. During the first shear, a 3.175 mm (1/8 inch) screen was used, during the second shear, a 1.59 mm (1/16 inch) screen was used, during the third shear, 0.79 mm (1/32 inch).

Fig. 19 is a block diagram illustrating the conversion of a fiber source into a fibrous material followed by densification of the fibrous material.

Fig. 20 shows the dense granular fibrous material.

Fig. 20A is a cross-sectional view of an empty granule in which the center of the void is aligned with the center of the granule.

Fig. 20B is a cross-sectional view of an empty granule in which the center of the void is not aligned with the center of the granule.

Fig. 20C is a cross-sectional view of the three-leaf granule

Fig. 21 is a block diagram showing a reversible increase in bulk density.

Fig. 22 is a schematic side view of the process of coating a fiber material with a binder and / or adding additives to the fiber material.

Fig. 23 is a schematic side view of a process for forming compacted fibrous material.

Fig. 24 is a partial perspective view of a pelletiser.

Fig. 25 is a schematic side view of the process for producing densified fibrous material.

Fig. 25A enlarges the area 25A in Fig. 25.

Fig. 26 is a block diagram illustrating imparting a desired shape to a fibrous material / curable resin combination and irradiating that desired shape to form a cured composite.

Fig. 27 is a partial perspective view of a gamma ray emitter.

Fig. 28 is an enlarged perspective view of the area 28 in Fig. 27.

Fig 29 is a photograph of a resin / fibrous material composite in the form of a platform on which part of the fibrous material of the composite is visible.

Fig. 30 is an enlarged view of the area in the frame of Fig. 29.

Figures 31A, 31B and 31C schematically show the production of a composite by means of a mold having a shaping surface.

Fig. 32 is a cross-sectional view of a resin / fibrous material composition having an inner portion that is substantially free of fibrous material and an outer portion surrounding the inner portion that comprises fibrous material.

EP 1 877 192 B9

Fig. 33 is a cross-sectional view of a transparent resin / fibrous material composite having an inner portion that substantially contains all fibrous material and an outer portion that substantially does not contain fibrous material surrounding the inner portion.

DETAILED DESCRIPTION [0105] In general, comparative fibrous materials, concentrated fibrous materials, and composites made from these materials and combinations of these materials have been disclosed.

[0106] Some of the fibrous materials disclosed herein are easily dispersed in a resin, such as a thermoplastic resin, and they can advantageously modify the rheology of the resin in a constant and predictable manner, resulting in a resin / fibrous material combination that may be, for example, easier to molding and extrusion. Many of the densified fibrous materials disclosed herein, such as in the form of granules or lumps, may be easier to handle, feed to machines, transport and mix with other materials. Many of the composites disclosed herein have excellent mechanical properties, such as abrasion resistance, compressive strength, fracture toughness, impact strength, flexural strength, tensile modulus, flexural modulus and elongation at break. Many of the composites, and especially many of the crosslinked composites, have a reduced tendency to break and / or crack at low temperatures and have improved high temperature stability and chemical resistance. Some of the pleasant-smelling composites, such as wood substitute composites, can arouse interest in shoppers and can provide amazing branding and marketing opportunities. Many of the disclosed composites have unique, pleasant or even striking visual features.

FIBER MATERIALS [0107] Fibrous materials are obtained from one or more fiber sources, for example, by shearing the fiber source to release the fibrous material.

[0108] Referring to Fig. 1, the fiber source 10 is sheared, for example in a rotary slicer, to provide the first fibrous material 12. This fibrous material can be used in the form in which it is supplied, for example to produce compacted fibrous materials and / or composites in comparative embodiments, or, according to the invention, the first fibrous material 12 is passed through a first screen 16 having an average mesh size of 1, 59 mm or smaller (1/16 inch, 0.0625 inch) to provide a second fibrous material 14. If desired, the fiber source 10 can be cut before shearing, for example with a chopper. For example, when paper is used as the fiber source 10, this paper can first be cut into strips that are, for example, 6.35 mm to 12.7 mm (1 / 4- to 1/2-inch) wide using shredder, for example, a shredder with counter-rotating shafts such as those manufactured by Munson (Utica, NY).

[0109] In some embodiments, shearing the fiber source 10 and passing the resulting fibrous material 12 through the first screen 16 is performed in parallel. Shearing and screening can also be carried out in a batch process.

[0110] For example, a slicer with rotary knives can be used to shear the fiber source 10 and screen the first fibrous material 12 in parallel. Referring to Fig. 2, the slicer with rotary knives 20 includes a hopper 22 into which a source of crushed fiber can be loaded

EP 1 877 192 B9

10 'produced by crushing the fiber source 10. The crushed fiber source 10' is cut between the fixed blades 24 and the rotary blades 26 to provide the first fibrous material 12. The first fibrous material 12 passes through a screen 16 having the dimensions described above and the second fibrous material 14 obtained is retained in container 30. To assist the collection of the second fibrous material 14, the container 30 may have a pressure lower than the nominal atmospheric pressure, e.g. at least 10 percent lower than the nominal atmospheric pressure, e.g. at least 25 percent lower than the nominal atmospheric pressure, at least 50 percent lower than the nominal atmospheric pressure or at least 75 percent lower than the nominal atmospheric pressure. In some embodiments, a vacuum source 50 is used to maintain a pressure lower than the nominal atmospheric pressure in the container.

[0111] Referring to Figs. 3-8, in some embodiments, the average mesh size of the first screen 16 is less than 0.79 mm (1/32 inch, 0.03125 inch), for example, less than 0.51 mm (1 / 50 inch, 0.02000 inch), less than 0.40 mm (1/64 inch, 0.015625 inch), less than 0.23 mm (0.009 inch), less than 0.20 mm (1/128 inch) , 0.0078125 inches), smaller than 0.18 mm (0.007 inches), smaller than 0.13 mm (0.005 inches) or even smaller than 0.10 mm (1/256 inches, 0.00390625 inches). The screen 16 is made by interleaving monofilaments 52 with a diameter suitable to obtain the holes of the desired size. For example, monofilaments can be made of metal, for example stainless steel. As the holes become smaller, the requirements for the structure of monofilaments may become greater. For example, for openings smaller than 0.40 mm it may be advantageous to produce screens from monofilaments made of a material other than stainless steel, e.g. titanium, titanium alloys, amorphous metals, nickel, tungsten, rhodium, rhenium, ceramics or glass. In some embodiments, the screen is made of a plate, e.g., a metal plate, having eyelets, e.g., cut into the plate by means of a laser.

[0112] In some embodiments, the second fibrous material 14 is cut and passed through a first screen 16 or a different size screen. In some embodiments, the second fibrous material 14 is passed through a second screen having an average mesh size equal to or smaller than the first screen 16.

[0113] Referring to Fig. 9, a third fibrous material 62 can be made from a second fibrous material 14 by shearing the second fibrous material 14 and passing the resulting material through a second screen 60 having an average mesh size smaller than the first screen 16.

[0114] Suitable fiber sources include cellulosic fiber sources, including paper and paper products, such as shown in Fig. 10A (polymer coated paper) and 10B (kraft paper), and lignocellulosic fiber sources, including wood and wood-related materials, example chipboard. Other suitable fiber sources include natural fiber sources, e.g., grass, rice husks, bagassa, cotton, jute, hemp, flax, bamboo, sisal agave, manila banana, straw, corn cobs, rice husks, coconut fibers; fiber sources high in α-cellulose, for example cotton; synthetic fiber sources, for example extruded yarn (oriented yarn or non-oriented yarn) or carbon fiber sources, inorganic fiber sources and metallic fiber sources. Natural synthetic fiber sources can be obtained from unused shreds of fibrous materials, e.g. debris, or they can be post-consumer waste, e.g. rags. When paper products are used as fiber sources, they may be unused materials, e.g., unused cuttings, or they may be used waste. Additional fiber sources are described in US Patent Nos. 6448307, 6258876, 6207729, 5973035 and 5952105.

[0115] In specific embodiments, the fiber source includes sawdust, for example, when sawing, machining or grinding deciduous wood or coniferous wood. Examples of deciduous wood include oak, maple, cherry (e.g. Brazilian cherry), walnut, mahogany, cypress or rosewood. Examples of coniferous wood include cedar (e.g. red and white cedar), pine, spruce, fir (e.g. Douglas fir wood) and redwood. In some embodiments, aromatic wood such as cedar or redwood is preferably used because it can give the composite a pleasant aroma. In some embodiments, the fragrance is added to sawdust. In some embodiments, it is preferred that the sawdust is sheared, for example using a rotary slicer with knives to deflect them.

[0116] Blends of any of the above sources of fiber or fibrous materials may be used, for example, to make composites or concentrated fibrous materials.

[0117] Generally, fibers of fibrous materials can have a relatively large average length-to-diameter ratio (e.g., greater than 20 to 1), even if they have been sheared more than once. In addition, the fibers of the fibrous materials described herein may have a relatively narrow length distribution and / or length to diameter ratio. Without wishing to be bound by any particular theory, it is now believed that the relatively large average length-to-diameter ratio and the relatively narrow length-and-diameter ratio are, at least in part, the reason that fibrous materials are easily dispersed into resin, for example molten thermoplastic resin. It is also believed that the relatively large average length-to-diameter ratio and the relatively narrow length-and-length ratio are at least in part the reason for the consistent properties of fibrous materials, the predictability of the rheology modification that fibrous materials cause in resin, ease, with which combinations of fibrous materials and resins are cast, extruded and injection molded, the ease with which fibrous materials pass through small, often winding channels and holes and the excellent surface quality that can be obtained with molded parts, e.g. glossy finish and / or finish substantially free of visible spots.

[0118] The average fiber widths (i.e., diameters) given herein are optically determined from about 5000 randomly selected fibers. Average fiber lengths are corrected weighted average lengths. BET surface areas (Brunauer, Emmet and Teller) are multipoint surface areas, and porosities are determined by mercury porosimetry.

[0119] The average length to diameter ratio of the second fibrous material 14 may be, e.g., above 10/1, e.g. above 25/1 or above 50/1. The average length of the second fibrous material 14 may be, for example, in the range of about 0.5 mm to 2.5 mm, for example in the range of about 0.75 mm to 1.0 mm, and the average width (i.e., diameter ) of the second fibrous material 14 may be, for example, in the range of about 5 μm to 50 μm, for example in the range of about 10 μm to 30 μm.

[0120] In some embodiments, the standard deviation of the length of the second fibrous material 14 is less than 60 percent of the average length of the second fibrous material 14, e.g., less than 50 percent of the average length, less than 40 percent of the average length, less than 25 percent of the average length, less than 10 percent of average length, less than 5 percent of average length or even less than 1 percent of average length.

[0121] In some embodiments, the BET surface area of ​​the second fibrous material 14 is greater than

2 2 2 0.5 m²/ g, e.g. greater than 1.0 m²/ g, larger than 1.5 m²/ g, larger than 1.75 m²/ g or even larger

EP 1 877 192 B9 ₂ than 5.0 m²/ G. The porosity of the second fibrous material 14 may be, for example, greater than 70 percent, e.g. greater than 80 percent, greater than 85 percent, or greater than 90 percent.

[0122] In some embodiments, the ratio of average length to diameter of the first fibrous material 12 to the ratio of average length to diameter of the second fibrous material 14 is, for example, less than 1.5, for example less than 1.4, less than 1.25 or even less than 1.1.

[0123] In specific embodiments, the second fibrous material 14 is re-cut and the resulting fibrous material is passed through a second screen having an average mesh size smaller than the first screen to provide the third fibrous material 62. In such cases, the ratio of the average length to diameter ratio of the second fibrous material 14 to the ratio of the average length to diameter of the third fibrous material 62 may be, for example, less than 1.5, for example less than 1.4, less than 1.25 or even less than 1.1.

[0124] In some embodiments, the third fibrous material 62 is passed through a third screen to produce a fourth fibrous material. The fourth fibrous material can, for example, be passed through a fourth screen to produce a fifth material. A similar screening process can be repeated as many times as desired to produce the desired fibrous material having the desired properties.

[0125] In some embodiments, the desired fibrous material includes fibers having an average length to diameter ratio greater than 5 and having a standard deviation of the fiber length that is less than sixty percent of the average length. For example, the average length to diameter ratio may be above 10/1, e.g. above 25/1 or above 50/1, and the average length may be in the range of about 0.5 mm to 2.5 mm, for example in the range from about 0.75 mm to 1.0 mm. The average width of fibrous material may be in the range of about 5 μm to 50 μm, for example in the range of about 10 μm to 30 μm. For example, the standard deviation may be less than 50 percent of the average length, e.g. less than 40 percent, less than 30 percent, less than 25 percent, less than 20 percent, less than 10 percent, less than 5 percent, or even less than 1 percentage of average length. The desired fibrous material may have, for example, a BET surface area greater than 0.5 m²/ g, e.g. greater than 1.0 m²/ g, greater than 1.5

2 2 2 m²/ g, larger than 1.75 m²/ g, larger than 5 m²/ g or even greater than 10 m²/ G. The desired material may have, for example, a porosity greater than 70 percent, e.g. greater than 80 percent, greater than 87.5 percent, greater than 90 percent, or even greater than 95 percent.

Examples of fibrous materials [0126] Micrographs were obtained using a JEOL 65000 field scanning electron microscope. Fiber lengths and widths (i.e., diameters) were determined by Integrated Paper Services, Inc., Appleton, WI, using an automated analyzer (TAPPI T271). The BET surface area was determined by Micromeritics Analytical Services, as well as porosity and bulk density.

Comparative Example 1 - Preparation of fibrous material from polymer-coated cardboard [0127] A pallet of 680 kg (1500 lbs) of new half-gallon juice cartons, made of unprinted polymer-coated white kraft cardboard having a bulk density of 0.32 g / cm³ (20 lb / ft³) obtained from International Paper. All cartons were folded flat and fed into a 3 hp Flinch Baugh shredder at a rate of about 6.8 kg to 9.1 kg (15 to 20 pounds) per hour

EP 1 877 192 B9. The shredder was equipped with two rotary blades 304.8 mm (12 inches), two fixed blades and a 7.62 mm (0.30 inch) outlet screen. The gap between fixed and rotating blades was set to 2.54 mm (0.10 inch). The stream from the crusher resembled confetti having a width in the range from 2.54 mm (0.1 inch) to 12.7 mm (0.5 inch), length in the range from 6.35 mm (0.25 inch) to 25, 4 mm (1 inch) and a thickness that corresponds to the thickness of the starting material (about 1.9 mm (0.075 inches)). Confetti-like material was fed to a Munson rotary cutter, Model SC30. The SC30 is equipped with four rotating blades, four fixed blades and an outlet screen having 3.175 mm (1/8 inch) holes. The gap between fixed and rotating blades was set to about 0.51 mm (0.020 inch). The rotary knife slicer cut confetti-like pieces along the edge of the knife, tearing the pieces apart and releasing fibrous material at a rate of about one pound per hour. The fibrous material had a BET surface area of ​​0.9748 m²/ g +/- 0.0167 m²/ g, porosity 89.0437 percent and bulk density (at 0.53 psia) 0.1260 g / ml. The average fiber length was 1.141 mm and the average fiber width was 0.027 mm, giving an average L / D ratio of 42: 1. The micrographs of the scanning electron microscope of fibrous material at a magnification of 25x and a magnification of 1000x are shown in Figures 11 and 12, respectively.

Comparative Example 2 - Manufacture of fibrous material from bleached kraft cardboard [0128] A 680 kg (1500 lb) pallet of freshly produced bleached white kraft cardboard 33 having a bulk density of 0.48 g / cm³ (30 lb / ft³) obtained from International Paper. The material was folded flat and fed into a 3 hp Flinch Baugh shredder at a rate of about 6.8 kg to 9.1 kg (15 to 20 pounds) per hour. The shredder was equipped with two rotary blades 304.8 mm (12 inches), two fixed blades and a 7.62 mm (0.30 inch) outlet screen. The gap between fixed and rotating blades was set to 2.54 mm (0.10 inch). The stream from the crusher resembled confetti having a width in the range from 2.54 mm (0.1 inch) to 12.7 mm (0.5 inch), length in the range from 6.35 mm (0.25 inch) to 25, 4 mm (1 inch) and thickness corresponding to the thickness of the starting material (about 1.9 mm (0.075 inch). Confetti-like material was fed to a Munson rotary cutter, Model SC30. The outlet screen had 3.175 mm (1/8 inch) holes. The gap between fixed and rotating blades was set to about 0.51 mm (0.020 inch). The rotary knife slicer cut confetti-like pieces, releasing fibrous material at a rate of about one pound per hour. The fibrous material had a surface area of ​​22

BET 1.1316 m²/ g +/- 0.0103 m²/ g, porosity 88.3285 percent and bulk density (at 0.53 psia) 0.1497 g / ml. The average fiber length was 1.063 mm and the average fiber width was 0.0245 mm, giving an average L / D ratio of 43: 1. The micrographs of the scanning electron microscope of fibrous material at a magnification of 25x and a magnification of 1000x are shown in Figures 13 and 14, respectively.

Example 3 - Production of double cut fibrous material from bleached kraft cardboard [0129] A 680 kg (1500 lb) pallet of freshly produced bleached white kraft cardboard 33 having a bulk density of 0.48 g / cm³ (30 pounds / foot³) obtained from International Paper. The material was folded flat and fed into a 3 hp Flinch Baugh shredder at a rate of about 6.8 kg to 9.1 kg (15 to 20 pounds) per hour. The shredder was equipped with two rotary blades 304.8 mm (12 inches), two fixed blades and a 7.62 mm (0.30 inch) outlet screen. The gap between fixed and rotating blades was set to 2.54 mm (0.10 inch). The outlet stream from the shredder resembled confetti (as above). Confetti-like material was fed to a Munson rotary cutter, Model SC30. Sieve

The exhaust ports had 1.59 mm (1/16 inch) holes. The gap between fixed and rotating blades was set to about 0.51 mm (0.020 inch). The rotary knife slicer cut confetti-like pieces, releasing fibrous material at a rate of about one pound per hour. The material obtained from the first shear was fed again to the same apparatus described above and sheared again. The resulting fibrous material had a BET surface area of ​​1.4408 m²/ g +/- 0.0156 m²/ g, porosity 90.8998 percent and bulk density (at 0.53 psia) 0.1298 g / ml. The average fiber length was 0.891 mm and the average fiber width was 0.026 mm, giving an average L / D ratio of 34: 1. The micrographs of the scanning electron microscope of fibrous material at a magnification of 25x and a magnification of 1000x are shown in Figures 15 and 16, respectively.

Example 4 - Manufacture of triple cut fibrous material from bleached kraft cardboard [0130] A 680 kg (1500 lb) pallet of freshly produced bleached white kraft cardboard 33 having a bulk density of 0.48 g / cm³ (30 lb / ft³) obtained from International Paper. The material was folded flat and fed into a 3 hp Flinch Baugh shredder at a rate of about 6.8 kg to 9.1 kg (15 to 20 pounds) per hour. The shredder was equipped with two rotary blades 304.8 mm (12 inches), two fixed blades and a 7.62 mm (0.30 inch) outlet screen. The gap between fixed and rotating blades was set to 2.54 mm (0.10 inch). The chopper outlet flow resembled confetti (as above). Confetti-like material was fed to a Munson rotary cutter, Model SC30. The outlet screen had 3.175 mm (1/8 inch) holes. The gap between fixed and rotating blades was set to about 0.51 mm (0.020 inch). The slicer with rotary knives cut confetti-like pieces along the edges of the knives. The material obtained from the first shear was fed again to the same device, and the screen was replaced with a 1.59 mm (1/16 inch) screen. The material was cut. The material obtained from the second shear was fed again to the same device, and the screen was replaced with a 0.79 mm (1/32 inch) screen. The material was cut. The resulting fibrous material had a BET surface area of ​​1.6897 m²/ g +/- 0.0155 m²/ g, porosity 87.7163 percent and bulk density (at 0.53 psia) 0.1448 g / ml. The average fiber length was 0.824 mm and the average fiber width was 0.0262 mm, giving an average L / D ratio of 32: 1. The micrographs of the scanning electron microscope of fibrous material at a magnification of 25x and a magnification of 1000x are shown in Figs. 17 and 18, respectively.

COMPARATIVE DENSITY OF FIBER MATERIALS [0131] Referring to Fig. 19, the fiber source is converted into a fibrous material. The fibrous material is then compacted. The binder and, optionally, other additives, such as fillers and antistatic agents, are added to the fibrous material before compacting. The fibrous material with the binder and all desired additives or fillers is compacted by applying pressure, e.g. or twin-screw). When applying pressure to heat the fiber material, heat may be used.

[0132] The fiber source can be converted to a fibrous material, for example, by mechanical means, for example, cutting or shearing the fiber source as discussed above.

EP 0 877 192 B9 [0133] All of the fibrous materials discussed above and others can be concentrated. For example, the fibers of the fibrous material may have, for example, an average length / diameter ratio (L / D) above 3, for example 5, 6, 7, 8, 10, 10, 25, 50 or more, for example 100. In some embodiments, the fibers of the fibrous material have an average length, e.g. 0.25 mm or more, e.g. 0.3 mm, 0.5 mm, 0.75 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm or more, e.g. 10 mm, and the maximum transverse dimension greater than 0.05 mm, e.g. 0.075 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm or more, for example 1 mm. If desired, the fibers of the fibrous material can be separated, for example, by sieving into fractions having different L / D ratios.

[0134] In some embodiments, the fibrous material has a bulk density of less than 0.25 g / cm before densification³for example 0.20 g / cm³, 0.15 g / cm³, 0.10 g / cm³, 0,05 g / cm³ or less, e.g. 0.025 ₃ g / cm³. Bulk density is determined in accordance with ASTM D1895B. In short, this method involves filling a measuring cylinder with a known volume with a sample and determining the mass of the sample. The bulk density is calculated by dividing the sample mass in grams by the known volume of the cylinder in cubic centimeters.

[0135] The fiber material can optionally be treated, for example, chemically or with steam, to make the fiber material fibers lipophilic, lipophobic, more compact and / or better dispersible or processable. For example, the fibrous material can be treated with plasma or chemically, for example with silanes.

[0136] Preferred binders include binders that are water-soluble, water swellable or have a glass transition temperature below 25 ° C as determined by differential scanning calorimetry. By water-soluble binders we mean binders having a solubility of at least about 0.05 weight percent in water. By water-swellable binders, we mean binders that increase in volume by more than 0.5 percent when exposed to water.

[0137] In some embodiments, binders that are water-soluble or water swellable contain a functional group that can form a bond, for example, a hydrogen bond, with the fibers of a fibrous material, for example, a cellulosic fibrous material. The functional group may be, for example, a carboxylic acid group, a carboxylate group, a carbonyl group, e.g. an aldehyde or ketone, a sulfonic acid group, a sulfonate group, a phosphoric acid group, a phosphate group, an amide group, an amino group, a hydroxyl group, e.g. an alcohol , and combinations of these groups, for example a carboxylic acid group and a hydroxyl group. Examples of specific monomers include glycerin, glyoxal, ascorbic acid, urea, glycine, pentaerythritol, monosaccharide or disaccharide, citric acid and tartaric acid. Suitable saccharides include glucose, sucrose, lactose, ribose, fructose, mannose, arabinose and erythrosis. Examples of polymers include polyglycols, polyethylene oxide, polycarboxylic acids, polyamides, polyamines, and polysulfonic acids and polysulfonates.

Specific examples of polymers include poly (propylene glycol) (PPG), poly (ethylene glycol) (PEG), _® poly (ethylene oxide), for example POLYOX^®, copolymers of ethylene oxide and propylene oxide, poly (acrylic acid) (PAA), polyacrylamide, polypeptides, polyethyleneimine, polyvinylpyridine, poly (sodium 4-styrene sulfonate) and poly (2-acrylamido-methyl-1-propanesulfonic acid).

[0138] In some embodiments, the binder includes a polymer that has a glass transition temperature below 25 ° C. Examples of such polymers include thermoplastic elastomers (TPE). Examples of TPE_® include polyether block amides such as those available under the tradename PEBAX^®, poly elastomers_® strowe, such as those available under the trade name HYTREL^®, and styrenic block copolymers such as

EP 1 877 192 B9 _® available under the trade name KRATON^®. Other suitable polymers having a glass transition temperature below 25 ° C include ethylene vinyl acetate (EVA), polyolefins, e.g. polyethylene, polypropylene, ethylene-propylene copolymers, and ethylene and alpha olefin copolymers, e.g. 1-octene, such as available_® under the trade name ENGAGE^®. In some embodiments, for example, when the fiber source used to make the fibrous material includes polymer-coated paper, the fibrous material is compacted without adding a separate low glass transition temperature polymer. For example, fibrous material made of polymer-coated paper can be concentrated by heating to a temperature above about 50 ° C, e.g. 75 ° C, 80 ° C, 90 ° C, 100 ° C or higher, e.g. 125 ° C, and using pressure in₂ heating time, e.g. pressure above about 345 kPa (50 lb / in²), e.g., 689 kPa (1000 lb / in²), 1724 kPa (250 lb / in²), 3447 kPa (500 lb / in²), 6895 kPa (100 lb / in²) or higher, e.g., 17237 kPa (2500 lb / in²).

[0139] In a specific embodiment, the binder is lignin, for example, natural or synthetically modified lignin.

[0140] In some embodiments, the fiber source used to make the fibrous material already includes a binder so that no additional binder is needed to achieve densification.

[0141] The binder may have other functions besides the binding of fibrous material. For example, when compacted fibrous material is used to make composites, the binder can act as a compatibility or bonding aid, helping to homogenize the composite resin and fibrous material. Specific examples of such binders include modified polymers that have been functionalized, for example, with maleic anhydride. Maleino anhydride grafted polymers_® they are available from DuPont ™ under the trade name FUSABOND^®. Other specific examples include modified ethylene-acrylate-carbon monoxide terpolymers and ethylene-vinyl acetate (EVA) copolymers, also available from DuPont ™. If desired, the binder may include a flavoring or fragrance.

[0142] A suitable amount of binder added to the fibrous material, calculated on a dry weight basis, is, for example, from about 0.01 percent to about 50 percent, for example 0.03 percent, 0.05 percent, 0.1 percent, 0.25 percent, 0.5 percent, 1.0 percent, 5 percent, 10 percent or more, such as 25 percent, based on the total weight of the densified fibrous material. The binder can be added to the non-admixed fibrous material in the form of a pure liquid, in the form of a liquid containing the binder dissolved in it, in the form of a dry powder or in the form of granules.

[0143] In other embodiments, the amount of binder added to the fibrous material is greater than 50 percent (calculated on a dry weight basis), e.g. greater than 55 percent, greater than 60 percent, greater than 65 percent, greater than 75 percent, or even greater than 85 percent. These embodiments may contain, for example, less than 90 percent of the polymer (e.g., thermoplastic polymer).

[0144] The densified fibrous material may be in the form of granules (Fig. 20) or lumps having different shapes, the desired shape being, in part, depending on the application. For example, when the granules or lumps are to be dry mixed with the resin, and then this plasticized mixture and the composite parts are to be formed from it, it is often convenient that the granules or lumps have a cylindrical shape, for example, having a maximum transverse dimension, example, 1 mm or more, e.g. 2 mm, 3 mm, 5 mm, 8 mm, 10 mm, 15 mm or more, e.g. 25 mm. Another convenient shape for making composites includes granules or lumps that resemble tiles, for example, having a thickness of 1 mm more, on

EP 1 877 192 B9 example 2 mm, 3 mm, 5 mm, 8 mm, 10 mm or more, e.g. 25 mm, width, e.g. 5 mm or more, e.g. 10 mm, 15 mm, 25 mm, 30 mm or more, e.g. 50 mm and length 5 mm or more, e.g. 10 mm, 15 mm, 25 mm, 30 mm or more, e.g. 50 mm.

[0145] Referring to Figs. 20A and 20B, the granules can be made by extrusion through a die having a solid central portion such that the respective granule is hollow. As shown, the void may generally lie in line with the center of the granule (Fig. 20A) or outside the line passing through the center of the granule (Fig. 20B). The production of hollow granules can reduce the cooling time required for complete curing of the granules and thus can increase the granule production rate. All granules may have the same or different cross-sections.

[0146] Referring to Fig. 20C, the cross-section of the granules may have, for example, a multi-leaf, e.g. three-leaf, as shown, or four-leaf, five-leaf, six-leaf or ten-leaf. The production of granules with such shapes in cross-section can reduce cooling time.

[0147] As discussed above, granules can be used, for example, to make composites. Granules or pellets can also be used as such, for example, as extended release absorbents or matrices. As sustained-release matrices, granules or pellets can be used, for example, to fertilize grass, to release drugs or biocides, or to release fragrances. As absorbents, granules or lumps can be used, for example, as animal bedding, packaging material or in dirt absorption systems. In embodiments in which the granules or pellets are used as sustained-release matrices, the granules or pellets may include a polymer, for example a degradable material. Exemplary polymers that degrade include polyhydroxy acids, for example polylactides, polyglycolides and copolymers of lactic acid and glycolic acid, poly (hydroxybutanoic acid), poly (hydroxyvaleric acid), poly [lactide-co-fc-caprolactone)], poly [glycolide-co- fc-caprolactone)], polycarbonates, poly (amino acids), poly (hydroxyalkanoates), polyanhydrides, polyorthoesters and mixtures of these polymers.

[0148] The compacted fibrous material, together with the resin, can be used to manufacture articles such as pipes, panels, formwork materials, boards, fasteners, sheets, blocks, bricks, posts, fences, elements, doors, shutters, awnings, curtains , signs, frames, window bands, boards, floor construction materials, tiles, railway sleepers, cuvette, tool holders, partitions, foils, wrapping films, tapes, boxes, baskets, shelves, covers, binders, dividers (partitions) , walls, mats, frames, book shelves, sculptures, chairs, tables, desks, toys, games, pallets, marinas, piers, boats, masts, fermentation chambers for sewage, car panels, computer cases, above and below covers of electrical installations, furniture , garden tables, benches, gazebos, trays, hangers, cake spatulas, boxes, book covers, walking sticks and rehabilitation balls.

[0149] Granules or pellets have different densities, the desired density, in part, depending on the application. For example, when granules or lumps are to be used to make composites, these granules

3333 or lumps may have a density of, for example, 0.11 g / cm3³, 0.15 g / cm³, 0.20 g / cm³, 0.25 g / cm³, 0,3

3 3 3 3 g / cm³, 0.4 g / cm³, 0.5 g / cm³, 0.6 g / cm³ or more, e.g. 0.8 g / cm³. When making composites, it is often preferable to choose a density that granules disintegrate under shear and / or heat, releasing the fibrous material from which the granules or lumps are formed. In many applications, the densified fibrous material can be replaced by a fibrous material because the densified fibrous material is transformed back into the fibrous material inside a processing device, e.g. an extruder or injection molding machine.

[0150] Referring to Fig. 21, a fibrous material having a low bulk density can be reversibly compacted without using a binder to the fibrous material having a higher bulk density.

₃

For example, fibrous material having a bulk density of 0.05 g / cm3³ can be compacted by sealing the fibrous material in a substantially airtight bag and then removing air from the bag. After removing air from the bag, the fibrous material may have a bulk density, for example,

3 3 3 3 greater than 0.3 g / cm³for example 0.5 g / cm³, 0.6 g / cm³, 0.7 g / cm³ or more, e.g. 0.85 g / cm³. This can be advantageous when it is desirable to transport the fibrous material to another location, such as a remote manufacturing plant, before concentrating the fibrous material with the binder. After piercing the air-impermeable bag, the densified fibrous material returns to almost initial bulk density, e.g., above 60 percent of initial bulk density, e.g., 70 percent, 80 percent, 85 percent or more, e.g., 95 percent of initial bulk density. To reduce the static electricity of the fibrous material, an antistatic agent can be added to it. For example, an antistatic chemical compound, e.g., a cationic compound, e.g., a quaternary ammonium compound may be added to the fiber material. Static electricity for fibrous material can also be reduced, for example, by induction, grounding or ionization. [0151] Fig. 22 explains the operation of the device for producing and processing fibrous material 70. A sheet of paper 73, e.g., a sheet of bleached recycled kraft paper, is unwound from a roll 72 and delivered to a fiberising apparatus 74, such as a rotary crusher. Sheet 73 is converted to fibrous material 12 'and fed to the fiber loading zone 80 by means of a conveyor 78. If desired, the fibrous material fibers can be separated, for example by screening, into fractions having different L / D ratios. In some embodiments, the fibrous material 12 'is continuously supplied to zone 80, and in other embodiments, the fibrous material is supplied in portions. A blower 82 in loop 84 is positioned at the fiber loading zone 80 and can move a gaseous carrier, e.g. air, at a speed and volume sufficient to introduce the fiber material 12 'into circulation in the direction indicated by arrow 88 in loop 84.

[0152] In some embodiments, the velocity of air moving in the loop is sufficient to uniformly disperse and transfer the fibrous material through the entire loop 84. In some embodiments, the flow rate is over 12.7 m / s (2,500 feet / minute), for example 25, 4 m / s (5000 feet / minute), 30.5 m / s (6000 feet / minute) or more, such as 38.1 m / s (7500 feet / minute).

[0153] The entrained fibrous material 12 'moving in the loop passes through the binder application zone 90, which is part of the loop 84 in which the binder is applied. During operations in the binder application zone 90, the liquid binder solution 96 is applied to the circulating fibrous material through nozzles 98, 99 and 100. The nozzles create a spray stream or mist of the binder material that falls on the fibers and coats them when the fibers pass the nozzles at a short distance. The valve 102 is operated to control the flow of liquid binding material to the respective nozzles 98, 99 and 100. After the desired amount of binding agent has been applied, the valve 102 closes.

[0154] In some embodiments, the binder application zone 90 is 0.61 m (two feet) to 30.5 m (one hundred feet) in length or more, for example 38.1 m (125 feet), 45.8 m (150 feet), 76.2 m (250 feet) long or more, such as 152.4 m (500 feet) long. Longer binder application zones allow binder application for a longer period of time as the fibrous material 12 'passes through the application zone 90. In some embodiments, the nozzles are spaced about three to about four feet apart along the entire length of loop 84.

[0155] In some embodiments, the binder provides coatings on the vast majority of the surfaces of each fiber of 12 'fibrous material, for example, fifty percent or more, for example sixty percent, seventy percent, seventy five percent or more, for example eighty percent. In some embodiments, the binder forms a coating that is about 1 micron thick or less, e.g. 0.5, 0.3 micron or less, e.g. 0.1 micron.

[0156] All of the additives and / or fillers described herein can, optionally, be added to loop 84 from the reservoir 106 during the circulation of fibrous material 12 'to produce a blend of fibers and additives.

[0157] In some embodiments, after applying the liquid binder material to the fibrous material 12 ', the coated fibrous material 110 is removed from loop 84 through a separator 112 which is selectively connected to loop 84 through section 114 and a gate valve 116. When the valve 116 is opened, another valve 120 is also opened to allow air to enter loop 84 and replace the outgoing air by separator 112. With the separator 112 in the loop the fibrous coating is collected in the separator 112 and then removed from the separator through outlet 122.

[0158] In some embodiments, the fibrous material is dried by means of an optional heater 130 before removing the material from loop 84. For example, the heated air can mix with the air entering through the conduit to accelerate the evaporation of liquid, for example water in which the substance is incorporated binding.

[0159] The coated fibrous material is poured loosely from the outlet 122 onto a conveyor 132 which moves it to the compaction station 150 shown in Fig. 23 or to the compaction station 200 shown in Fig. 24.

[0160] Referring to Fig. 23, the coated fibrous material 110 from the above portion of the description is delivered from the chest 152 through the slot 154 and onto the screen 156, for example the Fourdrinier screen. Excess water is sucked from the coated fibrous material 110 located on the screen 156 by a conventional vacuum system under a screen (not shown), leaving the non-concentrated fibrous material 160 which contains the binder. The uncompressed fibrous material 160 is then transferred to two sets of calender rollers 162, 164, each of which constitutes a separate nip through which the fibrous material passes. After passing through the shanks, the non-dried compacted material 170 passes into the drying section 180, where it is dried and then cut into granules or lumps.

[0161] In an alternative embodiment, the densified fibrous material can be made using a pelleting machine. Referring to Fig. 24, the pellet machine 200 has a hopper 201 containing non-concentrated fiber material 110. The hopper 201 is connected to a screw conveyor 204 driven by a speed-controlled motor 206, so that the non-concentrated fiber material 110 can be transported to the mixer 210, which mixes the non-concentrated material 110 by means of blades 212 rotated by the mixer motor 214. Other components, for example any of the additives and / or fillers described herein may be added through the inlet opening 220. If desired, when the fibrous material is in the mixer 210, it can be heated.

[0162] After mixing, the fibrous material passes from the mixer 210 through the chute 222 to the next screw conveyor 224. The chute 222, controlled by the actuator 223, enables the undisturbed flow of fibrous material from the mixer 210 to the screw conveyor 224. The screw conveyor 224 is rotated by motor 230 and is responsible for supplying fibrous material

EP 1 877 192 B9 into the matrix and rollers assembly 232. Specifically, the fibrous material is introduced into a hollow cylindrical matrix 240 which rotates about a horizontal axis and which has radially propagating holes in the matrix 250. The matrix 240 is rotated about the axis by a motor 242, which includes a power meter indicating the total energy consumption of the 242 engine.

[0163] The roll set 256 rotates on the inside of the die circumference 240, about axes parallel to the die axis 240, pressing the fiber material through the die holes 250, forming granules 300, which fall out of chute 301 and are collected and packaged.

[0164] The fibrous material discussed above can be concentrated using other methods. For example, with reference to Figs. 25 and 25A, the device 310 can be used to produce compacted fibrous material 311, e.g. a composite, e.g. As shown, the densified fibrous material 311 is made from a fibrous material-binder 313 combination by laminating the fibrous material-binder 313 combination between elements 312 and 314. Lamination is carried out, for example, using pressure alone or applying heat and pressure to the unpressed composite 322. The fibrous material-binder 313 combination may optionally include any of the additives discussed above.

[0165] The device 310 includes first and second members 312 and 314 provided from rollers 321 and 323, respectively, and a hopper 320 containing fibrous material, binder and all additives. The fibrous material, binder and all additives are supplied between components 312 and 314 to form an uncompressed 322 composite. The uncompressed composite 322 is then passed through a series of hot rollers 330, 332, 334, 336, 338, 340 and 342, forming a winding path, and then through the grips 350, 352 and 354, 356 to produce the composite 311. The hopper 320 can be used provide mixers to ensure that fibrous material, binder and all additives do not lump or stick to the walls during power supply. The uncompressed composite 322 partially compacts after passing through a winding path formed by the heated rollers 330, 332, 334, 336, 338 and 340, and then completely compacts to produce the composite 311 by passing through shanks 350, 352 and 354, 356.

[0166] In some embodiments, the fiber source used to make the fibrous material already contains a binder. In this case, no additional binder is needed to achieve thickening. For example, when the fiber source used to make the fibrous material includes polymer-coated paper, the fibrous material is compacted without adding a separate binder, for example a polymer with a low glass transition temperature.

[0167] The pinch rollers 354, 356 can rotate in such a way that each has a surface speed greater than the pinch rolls 350, 352. In this configuration, the densified fibrous material is stretched between the pinch rollers 350, 352 and the pinch rollers 354, 356. In some embodiments, stretching of the densified fibrous material is desirable because it can improve many of the mechanical properties of the composite, e.g. flexural modulus, flexural strength and tensile strength.

[0168] Elements, e.g., webs, may be made, for example, of polymer-coated paper, plastic film, plastic raw material, or textile material being upholstery, e.g. textile material being woven or non-woven fabric. When it is desired to minimize the amount of material of the element in the densified fibrous material, the thickness T1 and T2 of the elements 312 and 314, respectively, may be, for example, less

EP 1 877 192 B9 than 1.27 mm (0.050 inches), e.g. 1.0 mm (0.040 inches), 0.64 mm (0.025 inches), 0.51 mm (0.020 inches), 0.25 mm (0.010) inch), 0.127 mm (0.005 inch) or less, e.g. 0.064 mm (0.0025 inch). When it is desired to maximize the mechanical properties of the densified fibrous material, the thickness T1 and T2 of the elements 312 and 314, respectively, may be above 1.27 mm (0.050 inches), e.g. 1.52 mm (0.060 inches), 1.65 mm (0.065 1.90 mm (0.075 inches), 2.16 mm (0.085 inches), 2.54 mm (0.100 inches), 3.81 mm (0.150 inches), 6.35 mm (0.250 inches), 19, 05 mm (0.75 inches) or more, such as 50.8 mm (2.00 inches).

[0169] In some embodiments, rolls 330, 332, 334, 336, 338 and 340 are heated to a temperature in the range of 149 ° C (300 ° F) to about 260 ° C (500 ° F). In embodiments where plastic film is used as the element material, the role of these temperatures is to quickly soften the polymer material of which the film is made.

[0170] In some embodiments, the heated rolls 330, 332, 334, 336, 338 and 340 are in the range of about 127 mm (5 inches) in diameter to about 1067 mm (42 inches) in diameter, for example 254 mm (10 inches), 381 mm (15 inches), 508 mm (20 inches), 635 mm (25 inches) or more, such as 914.4 mm (36 inches).

[0171] The feeding rate of the element may be, for example, in the range of from about 0.018 m / s (3.5 feet per minute) to about 1.27 m / s (250 feet per minute), e.g. 0.13 m / s s (25 feet per minute), 0.25 m / s (50 feet per minute), 0.51 m / s (100 feet per minute) or more, e.g. 0.89 m / s (175 feet per minute) .

[0172] The pressure rollers 350, 352 and 354, 356 may be hot or unheated. If they are heated, they are typically heated to a temperature less than heated rolls 330, 332, 334, 336, 338 and 340 to allow cooling and solidification of the materials that will form the densified fibrous material. For example, the pressure rollers 350, 352 and 354, 356 are heated to a temperature in the range of 38 ° C (100 ° F) to about 149 ° C (300 ° F). The pressure between the pressure rollers is, for example, at least about 8930 kg / m (500 pounds per linear inch), for example, 17860 kg / m (1000 pounds per linear inch), 44650 kg / m (2500 pounds per linear inch), 89300 kg / m (5000 pounds per linear inch) or more, for example 446500 kg / m (25000 pounds per linear inch).

[0173] In some embodiments, the thickness T 'of the densified fibrous material 311 is at least about two times smaller than the thickness T of the unpressed composite 322, e.g., three times, four times, five times or less, e.g. Thus, the bulk density of the densified fibrous material is greater than that of the unpressed composite. For example, the density of the unpressed

3 The composite may be, for example, less than 0.25 g / cm3³for example 0.20 g / cm³, 0.15 g / cm³, 0.10 g / cm³, 33

0.05 g / cm³ or less, for example, 0.025 g / cm³and the bulk density of the densified fibrous material

3 3 may be, for example, above about 0.3 g / cm³, for example, 0.4 g / cm³, 0.5 g / cm³, 0.6 g / cm³ or more, ₃ for example 0.8 g / cm³.

[0174] The cooled condensed fibrous material 311 may be rolled or cut into sheets. Compaction of fibrous material between elements can be advantageous when it is desired to transport the fibrous material to another location, for example, a remote manufacturing plant. After transporting to this other location, the densified fibrous material can be converted back into the fibrous material by any of the methods discussed herein.

[0175] Alternatively, the cooled concentrated fibrous material can be used in various applications. For example, it can be used for silencing, insulation, structural elements, durable crates and partition walls.

[0176] Although embodiments of the fibrous material have been described in which the binder is applied to the fibrous material by spraying with a binder solution, for example a binder solution containing a binder dissolved in water, in some embodiments the binder is applied to the material fibrous as an unadulterated liquid binder solution or as a dry powder. The binder can also be applied as a gaseous material.

[0177] Although embodiments are shown in which the fibrous material is transformed into a compacted fibrous web, and then the compacted fibrous material is immediately cut into granules or lumps, in some embodiments, the compacted fibrous material is first received as a role. The compacted fibrous web can be used, for example, as an absorbent mat material or transported to a remote industrial plant where it is converted into granules or pellets. The material being the compacted fibrous web may be a convenient form for the transportation of the fibrous material due to its higher bulk density.

[0178] Although embodiments have been described in which monolayer elements 312 and 314 are used to make the compacted fibrous material 311, for example a composite, multilayer elements are used in some embodiments. For example, each of the elements may have, for example, two layers, three layers, five layers or more, for example seven layers. In addition, although densified fibrous materials have been described in which a layer of fibrous material is sandwiched between two elements, in some embodiments, the densified fibrous material is produced by pressing the fibrous material that is under a single element.

Examples of concentrated fibrous materials

Example 5 - Preparation of densified fibrous material from bleached kraft paper without added binder. A fibrous material was prepared according to Example 2. About 0.45 kg (1 pound) of water was sprayed on every 4.5 kg (10 pounds) of fibrous material. The fibrous material was compacted using California Pellet Mill 1100 operating at 75 ° C. Granules having a bulk density in the range of about 0.11 g / cm were obtained³ (7 pounds / ft³) up to about 0.24 g / cm³ (15 pounds / ft³).

Example 6- Preparation of densified fibrous material from bleached kraft paper with a binder [0180] Fibrous material was prepared according to Example 2.

_™ [0181] 2 wt. POLYOX stock solution^™ WSR N10 (polyethylene oxide) in water.

[0182] About 0.45 kg (1 pound) of the stock solution was sprayed for every 4.5 kg (10 pounds) of fibrous material. The fibrous material was compacted using California Pellet Mill 1100 operating at 33 ° C

75 ° C. Granules having a bulk density in the range of about 0.24 g / km were obtained³ (15 pounds / ft³) up to about 0.64 g / cm³ (40 pounds / ft³).

COMPARATIVE COMPOSITES FIBER MATERIAL / RESIN

EP 0 877 192 B9 [0183] Composites comprising any of the above-mentioned fibrous materials (including densified fibrous materials) or mixtures of any of the above fibrous materials, for example a first 12 or second 14 fibrous material, and a resin, for example a thermoplastic resin or a thermosetting resin can be made by combining the desired fibrous material and the desired resin. The desired fibrous material can be combined with the desired resin, for example, by mixing the fibrous material and resin in an extruder or other mixer. To form the composite, the fibrous material can be combined with the resin as such or as a densified fibrous material that can be re-opened during the bonding.

[0184] Examples of thermoplastic resins include rigid and elastomeric thermoplastics. Rigid thermoplastics include polyolefins (e.g. polyethylene, polypropylene or polyolefin copolymers), polyesters (e.g. polyethylene terephthalate), polyamides (e.g. nylon 6, 6/12 or 6/10) and polyethyleneimines. Examples of elastomeric thermoplastic resins include elastomeric styrene copolymers (e.g. styrene-ethylene-butylene-styrene copolymers), polyamide elastomers (e.g. polyether polyamide copolymers) and ethylene vinyl acetate copolymer.

[0185] In some embodiments, the thermoplastic resin has a melt flow rate in the range of 10 g / 10 minutes to 60 g / 10 minutes, for example in the range of 20 g / 10 minutes to 50 g / 10 minutes or in the range of 30 g / 10 minutes to 45 g / 10 minutes, measured in accordance with ASTM 1238.

[0186] In some embodiments, compatible blends of any of the above thermoplastic resins may be used.

[0187] In some embodiments, the thermoplastic resin has a polydispersity index (PDI), i.e. a ratio of weight average molecular weight to number average molecular weight, above 1.5, e.g. above 2.0, above 2.5, above 5.0, above 7.5 or even above 10.0.

[0188] In specific embodiments, polyolefins or mixtures of polyolefins are used as the thermoplastic resin.

[0189] Examples of thermosetting resins include natural rubber, butadiene rubber and polyurethanes.

[0190] Generally, the fibers of fibrous materials can have a relatively large average length-to-diameter ratio (e.g., above 20 to 1), even if they have been cut more than once. In addition, the fibers of the fibrous materials described herein may have a relatively narrow length distribution and / or length to diameter ratio. Without wishing to be bound by any particular theory, it is now believed that the relatively large average length-to-diameter ratio and the relatively narrow length-and-diameter ratio are, at least in part, the reason that fibrous materials are easily dispersed into resin, for example molten thermoplastic resin. It is also believed that the relatively large average length-to-diameter ratio and the relatively narrow length-and-length ratio are at least in part the reason for the consistent properties of fibrous materials, the predictability of the rheology modification that fibrous materials cause in resin, ease, with which combinations of fibrous materials and resins are cast, extruded and injection molded, the ease with which fibrous materials pass through small, often winding channels and holes, and the excellent surface quality that can be obtained with molded parts, e.g. a glossy finish and / or a finish substantially free of visible spots, when desired.

[0191] A chemical foaming agent may be used during the production of the composite, for example an endothermic or exothermic foaming agent and / or a gas, for example nitrogen or carbon dioxide may be injected into the mixture. This can be advantageous when producing articles with a large cross-section,

EP 1 877 192 B9 for example to prevent dripping, reduce the density of parts and / or reduce the cooling time. Chemical_® foaming agents are available from Clariant Corporation, for example, under the trade name HYDROCEROL^®.

ADDITIVES [0192] Any of the following additives may be added to the fibrous materials, densified fibrous materials and composites described herein. Additives, for example, in solid, liquid or gaseous form may be added, for example, to the combination of fibrous material and resin. You can add any of the following add-ons. Additives include fillers such as calcium carbonate, graphite, wollastonite, mica, glass, fiberglass, silica and talc; inorganic flame retardants such as lithium hydroxide or magnesium hydroxide; organic flame retardants such as chlorinated or brominated organic compounds; ground construction waste; ground rubber from tires; carbon fibers; or metallic fibers or powders (e.g. aluminum, stainless steel). These additives can strengthen, extend or change electrical, mechanical or compatibility properties. Other additives include lignin, fragrances, coupling agents, homogenizing agents, e.g., maleic anhydride-functionalized polypropylene, processing aids, glidants, e.g., fluorinated polyethylene, plasticizers, antioxidants, opacifiers, heat stabilizers, dyes, foaming agents, impact modifiers , polymers, e.g. degradable polymers, photostabilizers, biocides, antistatic agents, for example, stearates or ethoxylated fatty acid amides. Suitable anti-static compounds include conductive carbon blacks, carbon fibers, metal fillers, cationic compounds, e.g., quaternary ammonium compounds, e.g., N- (3-chloro-2-hydroxypropyl) -trimethylammonium chloride, alkanolamides and amines. Exemplary polymers that degrade include polyhydroxy acids, for example polylactides, polyglycolides and copolymers of lactic acid and glycolic acid, poly (hydroxybutanoic acid), poly (hydroxyvaleric acid), poly [lactide-co-(ecaprolactone)], poly [glycolide-co ( e-caprolactone)], polycarbonates, poly (amino acids), poly (hydroxyalkanoate), polyanhydrides, polyorthoesters and mixtures of these polymers.

[0193] When the additives described are included, they can be present in amounts, calculated on the dry matter, from less than 1 percent up to 80 percent, based on the total weight of the fibrous material. More typically, the amounts range from about 0.5 percent to about 50 percent by weight, e.g., 5 percent, 10 percent, 20 percent, 30 percent or more, e.g., 40 percent.

[0194] Any of the additives described herein may be encapsulated, for example spray dried or microencapsulated, for example to protect the additives from heat or moisture during handling.

[0195] Fibrous materials, densified fibrous materials, resins or additives may be colored. For example, the fibrous material can be colored before combining with the resin and mixing to form composites. In some embodiments, this dyeing can help mask or hide fibrous material, especially large clusters of fibrous material, in molded or extruded portions, when desired. Such large clusters, when present at relatively high density, can be seen as spots on the surfaces of molded or extruded parts.

[0196] For example, the desired fibrous material can be colored using an acid dye, direct dye or reactive dye. Such dyes are available from Spectra Dyes, Kearny, NJ or Keystone Aniline Corporation, Chicago, IL. Specific examples of dyes include SPECTRA ™ LIGHT YELLOW 2G,

EP 1 877 192 B9

SPECTRACID ™ YELLOW 4GL CONC 200, SPECTRANYL ™ RHODAMINE 8, SPECTRANYL ™ NEUTRAL RED B, SPECTRAMINE ™ BENZOPERPURINE, SPECTRADIAZO ™ BLACK OB, SPECTRAMINE ™ TURQUOISE G, and SPECTRAMINE ™ GRAY LVL Spectra 200% Dy, each available.

[0197] In some embodiments, the color concentrates for resins containing pigments are mixed with the dyes. When such mixtures are then mixed with the desired fibrous material, the fibrous material can be colored in-situ during this mixing. Coloring concentrates are available from Clariant.

[0198] It may be advantageous to add aromatic or fragrance to the fibrous materials, concentrated fibrous materials or composites. For example, it may be advantageous for the composites to have the smell and / or appearance of natural wood, for example cedar wood. For example, a fragrance, e.g. a natural wood fragrance, can be mixed with the resin used to make the composite. In some embodiments, the fragrance is mixed directly with the resin as an oil. For example, the oil can be mixed with the resin using a roller mill, on_® example of a Banbury mixer^®or an extruder, for example a twin screw extruder with counter-rotating screws. An example of a Banbury mixer^® is a Banbury mixer^® F-Series, produced by _™

Farrel. An example of a twin screw extruder is WP ZSK 50 MEGAcompunder^™, produced by

Krupp Werner & Pfleiderer. After mixing, the pleasant-smelling resin can be added to the fiber material and extruded or molded. Alternatively, masterbatches of resins containing zap substances_™ stocks are commercially available from International Flavors and Fragrances under the trade name PolyIff^™ or from the RTP company. In some embodiments, the amount of fragrance in the composite ranges from about 0.005% by weight to about 10% by weight, for example in the range of from about 0.1% to about 5% or 0.25% to about 2.5%.

[0199] Other natural wood fragrances include those derived from evergreen plants or redwoods. Other fragrances include substances derived from peppermint, cherry, strawberry, peach, lime, spearmint, cinnamon, anise, basil, bergamot, black pepper, camphor, chamomile, citronellal, eucalyptus, pine, fir, geranium, ginger, grapefruit, Jasmine, Juniper, Lavender, Lemon, Tangerine, Marjoram, Musk, Myrrh, Orange, Patchouli, Rose, Rosemary, Sage, Sandalwood, Tea Tree, Thyme, Wintergreen Oil, Ilangan Oil, vanilla, a new car or a mixture of these fragrances. In some embodiments, the amount of fragrance in the fibrous material-fragrance combination ranges from about 0.005% by weight to about 20% by weight, e.g., from about 0.1% to about 5% or 0.25% to about 2, 5%.

[0200] Although fibrous materials such as cellulosic and lignocellulosic fibrous materials have been described, other fillers can be used to make composites. For example, inorganic fillers such as calcium carbonate (e.g., precipitated calcium carbonate or natural calcium carbonate), aragonite clay, rhombic clays, calcite clay, rhombohedral clays, kaolin clay, bentonite clay, phosphate (V) dicalcium, phosphate (V) tricalcium, calcium pyrophosphate, insoluble sodium (V) metaphosphate, precipitated calcium carbonate, magnesium orthophosphate, trimagnesium phosphate, hydroxyapatites, synthetic apatites, alumina, silica xerogel, metal-aluminosilicate complexes, sodium and aluminum silicates, zirconium silicate, silicon dioxide, or combinations of inorganic additives. Fillers may have a particle size, e.g., above 1 micron, e.g. above 2 microns, 5 microns, 10 microns, 25 microns, or even above 35 microns.

[0201] Nanometer scale fillers can also be used alone or in combination with fibrous materials. These fillers may be in the form of, for example, particles, plates or fibers. For example, clays on a nanometer scale, silicon and carbon nanotubes, and silicon and carbon nanowires can be used. The filler may have a transverse dimension smaller than 1000 nm, e.g. smaller than 900 nm, 800 nm, 750 nm, 600 nm, 500 nm, 350 nm, 300 nm, 250 nm, 200 nm, smaller than 100 nm or even smaller than 50 nm.

[0202] In some embodiments, the nanometer scale clay is montmorillonite. Such clays are available from Nanocor, Inc. and Southern Clay Products and described in US Patent Nos. 6849680 and 6737464. Clays can be surface treated prior to mixing, for example, with resin or fibrous material. For example, clay can be surface treated so that its surface acquires ionic, e.g. cationic or anionic, properties.

[0203] Aggregated or agglomerated fillers on a nanometer scale or fillers on a nanometer scale that are combined into supramolecular structures, for example, self-ordered supramolecular structures, can also be used. Aggregated or supramolecular fillers may have an open or closed structure and may have different shapes, for example, cages, tubes or spherical.

STRUCTURES [0204] Any composite described herein may be in the form of articles such as pipes, panels, boarding materials, boards, fasteners, sheets, blocks, bricks, columns, fences, elements, doors, shutters, awnings, curtains, signs, frames, window bands, boards, floor construction materials, tiles, railway sleepers, cuvette, tool holders, partitions, films, wrapping films, tapes, boxes, baskets, shelves, covers, binders, dividers, dividers (walls), walls, mats, frames, bookshelves, sculptures, chairs, tables, desks, toys, games, pallets, marinas, piers, boats, masts, fermentation chambers, car panels, computer cases, above and below covers of electrical installations, furniture, garden tables, benches, garden arbors, trays, hangers, cake spatulas, cases, book covers, walking sticks, rehabilitation balls, household items and house construction elements.

RADIO-CURED COMPOSITES [0205] Referring to Fig. 26, radiation-cured composites can be made, for example, by combining fibrous material, which includes separate fibers, with a radiation-curable resin, e.g. a thermoplastic resin (e.g., high melt flow polypropylene) to provide a fibrous material / curable resin combination. The fibrous material may have, for example, an average length to diameter ratio above 5 and a standard deviation of the fiber length, which is, for example, less than eighty-five percent of the average fiber length. A combination of fibrous material / curable resin is formed, for example, using extrusion or injection molding, for example, a boarding board and irradiated, for example, with ionizing radiation (e.g. electron beams, X-rays or gamma rays) to at least partially crosslinking the curable resin.

[0206] In specific embodiments, gamma radiation is used to cross-link the curable resin. Referring to Figs. 27 and 28, the gamma 400 emitter includes 408 gamma radiation sources, e.g., granules⁶⁰What, work table 410 holding the composite to be irradiated29

EP 1 877 192 B9, as well as a warehouse 412, for example made of many steel plates, all of which are located in a concrete safety chamber 402 which includes a passage requiring bypassing the wall, as in a maze, 404 behind lead-lined door 406. Warehouse 412 includes a plurality of channels 420, e.g., sixteen or more channels, allowing 408 gamma radiation sources to pass through the warehouse 412 on their path near the work table 410.

[0207] During operation, the composite to be irradiated is placed on the work table 410. The gamma radiator is positioned to deliver the desired dose rate and the monitoring equipment is connected to the experimental block 440. Then the operator leaves the safety chamber 402, passes through a passage that requires bypassing the wall 404 and through the 406 lead-lined door. The operator uses control panel 442, ordering the computer to raise radiation sources 408 to working position using cylinder 441 connected to hydraulic pump 444.

[0208] In embodiments in which the irradiation is carried out by means of electromagnetic radiation (e.g. as above), electromagnetic radiation may have energy per photon (in electron volts), e.g. above 10² eV, e.g. above 10³, 10⁴, 10⁵, 10⁶ or even above 10⁷ eV. In some embodiments, electromagnetic radiation has energy per photon in the range of 10⁴ up to 10⁷, for example in the range of 10⁵ up to 10⁶ eV. Electromagnetic radiation can have a frequency, e.g. above 10¹⁶ Hz, above 10¹⁷ Hz, 10¹⁸, 10¹⁹, 10²⁰ or even above 10²¹ H. In some embodiments, electromagnetic radiation has a frequency in the range of 10¹⁸ up to 10²² Hz, for example in the range of 10¹⁹ up to 10²¹ H.

[0209] In some embodiments, an electron beam is used as the radiation source. An electron beam can be generated, for example, by means of electrostatic generators, cascade generators, transformer generators, low-energy accelerators with a scanning system, low-energy accelerators with a linear cathode, linear accelerators and pulse accelerators. Electrons as an ionizing radiation source may be useful, for example, for composites having a relatively thin cross-section, e.g. below 0.5 inch, e.g. below 0.4 inch, 0.3 inch, 0.2 inch or below 0.1 whole. In some embodiments, the energy of each electron in the electron beam is from about 0.3 MeV to about 2.0 MeV (million electron volts), for example from about 0.5 MeV to about 1.5 MeV or from about 0.7 MeV to about 1.25 MeV.

[0210] In some embodiments, the irradiation (from any radiation source) is conducted until the fibrous material / curable resin combination receives a dose of at least 0.25 Mrad, for example at least 1.0 Mrad, at least 2.5 Mrad, at least 5.0 Mrad or at least 10.0 Mrad. In some embodiments, the irradiation is carried out until the fibrous material / curable resin combination receives a dose in the range of 1.0 Mrad to 6.0 Mrad, for example in the range of 1.5 Mrad to 4.0 Mrad.

[0211] In some embodiments, the irradiation is performed with a dose rate in the range of 5.0 to 1500.0 kilorades / hour, for example in the range of 10.0 to 750.0 kilorades / hour or in the range from 50.0 to 350 0 kilorady / hour.

[0212] The radiation curable resin may be, for example, a thermoplastic or thermosetting resin (e.g. a thermosetting casting resin). For example, the radiation curable resin may be a polyolefin, e.g. polyethylene (e.g., polyethylene copolymer), polypropylene (e.g., polypropylene copolymer), polyester (e.g., polyethylene terephthalate), polyamide (e.g., nylon 6, 6/12 or 6/10), polyethyleneimine, elastomeric styrene copolymers (e.g. styrene-ethylene copolymers)

EP 1 877 192 B9 butylene-styrene), a polyamide elastomer (e.g. polyether-polyamide copolymer), ethylene-vinyl acetate copolymer, casting polyurethane, casting silicone or compatible mixtures of these resins.

[0213] In certain specific embodiments, the resin is a polyolefin that has a polydispersity above 2.0, e.g., above 3.0, above 3.5, above 4.0, above 4.5, above 5.0, above 7, 5 or even above 10.0 (measured by high temperature gel chromatography compared to polystyrene standards, see, for example, ASTM D6474-99). High polydispersity can improve the impact resistance of hardened composite. In some embodiments, the polyolefin has a melt flow rate greater than 10.0 g / 10 minutes, for example, greater than 15.0, greater than 20.0, greater than 25.0, greater than 30.0, or even greater than 50, 0 g / 10 minutes (measured according to ASTM D1238, 230 ° C / 2.16 kg). The high melt flow rate can facilitate the production of the composite, for example, by reducing the shear heat during the production of the composite.

[0214] In a specific embodiment, the resin is a 50:50 weight percent blend of melt flow rate polypropylene (MFR) melt flow rate and MFR 50 polypropylene. Polypropylenes are available from Sunoco Chemical.

[0215] Crosslinked composites may include any fillers or any combination of fillers and / or additives disclosed herein.

[0216] Although the embodiment of Fig. 27 illustrates a "dry" safety system, water systems are also possible. Although the embodiment of Fig. 27 illustrates irradiation of the composite under normal conditions, the composite can be cooled during irradiation. Although the embodiment of Fig. 27 illustrates irradiation in a normal air atmosphere, the irradiation may be in an inert atmosphere, for example nitrogen or argon.

[0217] Radiation chemistry is described by Ivanov in "Radiation Chemistry of Polymers" (translation from Russian), VSP Press BV, Ultrech, The Netherlands (ISBN 90-6764-137-5), 1992.

COMPOSITES HAVING CERTAIN VISUAL ATTRIBUTES [0218] Referring to Figs. 29 and 30, the composite 500, for example in the form of a platform (shown) includes resin and fibrous material 504 and has an outer surface 505. Part of the fibrous material is visible on, in, or just below the outer surface of the composite. Such composites can have unique, pleasant or even striking visual features and at the same time have the desired mechanical properties, for example, flexural strength and impact resistance.

[0219] The composite can be made, for example, by combining resin and fibrous material 14 to provide a resin / fibrous material combination and compressing the resin / fibrous material combination to provide a composite having an outer surface. Generally, the resin, the fibrous material and the conditions for making the composite are selected such that the fibrous material is visible in, on or just below the outer surface, and not hidden deep below the surface where it would not be visible. For example, in the case of opaque or translucent material, the fibrous material is visible under the outer surface of the composite when it is at a distance, for example, less than 2.54 mm (0.100 inch), for example less than 1.27 mm (0.050 inch) , less than 0.635 mm (0.025 inches), less than 0.254 mm (0.010 inches), less than 0.127 mm (0.005 inches), less than 0.064 mm (0.0025 inches) or less than 0.0254 mm (0.001 inches) from the outer surface.

[0220] The composites can be made using any mechanical equipment for processing plastics, for example injection molding equipment and compression molding equipment or extrusion molding equipment.

[0221] The resin may be thermoplastic or thermosetting. The thermoplastic resin may be, for example, a polyolefin, such as polyethylene (e.g. polyethylene copolymer) or polypropylene (e.g. polypropylene copolymer); polyester such as polyethylene terephthalate (PET); polyamide such as nylon 6, 6/12 or 6/10; an elastomeric styrene copolymer such as a styrene-ethylene-butylene-styrene copolymer; polyamide elastomers such as polyether-polyamide copolymer; ethylene vinyl acetate copolymer or mixtures of these resins. [0222] To provide unique composites, it is often desirable to use a relatively viscous resin that can improve the visibility of the fiber, preventing the fiber material from "slipping" under the outer surface where it would be invisible.

[0223] In some embodiments, the resin is a polyolefin, e.g. polypropylene, having a melt flow rate less than 50 g / 10 minutes, e.g. less than 25 grams / 10 minutes, less than 20 grams / 10 minutes, less than 17 grams / 10 minutes, less than 15 grams / 10 minutes, less than 10 grams / 10 minutes, less than 7.5 grams / 10 minutes, less than 5 grams / 10 minutes, less than 2.5 grams / 10 minutes or even less than 1 gram / 10 minutes. The lower melt flow limit will depend on the treatment technique used to make the composite, for example injection molding or extrusion. In the case of injection molding, it may be desirable for the melt flow rate to be greater than 0.5 grams / 10 minutes. For compression molding and extrusion, it may be desirable for the melt flow rate to be greater than 0.1 grams / 10 minutes. Melt flow rates are measured using ASTM D1238 at 230 ° C and 2.16 kg, the disclosure of which is incorporated by reference in its entirety.

[0224] The fibrous material used can be, for example, densified fibrous material created by applying pressure to the fibrous material (optionally containing a binder), for example, by passing the fibrous material through a grip between counter-rotating bias rollers or by passing the fibrous material through a pelleting machine, as discussed above. The compacted fibrous material can be, for example, in the form of granules or lumps or other lumps of various shapes. The density of the densified fibrous material may, for example, be greater than

3 3 3

0.11 g / cm^{3 * * * * * * 10}, e.g. greater than 0.15 g / cm³, greater than 0.20 g / cm³, greater than 0.25 g / cm³, bigger than

3 3 3

0.3 g / cm³, greater than 0.4 g / cm³, greater than 0.5 g / cm³ or even greater than 0.6 g / cm³. It is desirable to select such a density that the compacted material "disintegrates" under shear and / or heat, releasing the fibrous material or agglomerated fibrous material. Generally, it is desirable to get concentrated₃ the fibrous material had a density less than 0.9 g / cm³.

[0225] Fibers of fibrous materials may have a relatively large average length to diameter ratio (for example above 20 to 1). The average ratio of length to diameter of the second fibrous material 14 may be, e.g., greater than 10/1, e.g. greater than 25/1 or greater than 50/1. The average length of the second fibrous material 14 may be, for example, in the range of from about 0.5 mm to 2.5 mm, for example in the range of from about 0.75 mm to 1.0 mm, and the average width (i.e. diameter) of the second fibrous material 14 may be, for example, in the range of from about 5 μm to 50 μm, for example, in the range of from about μm to 30 μm.

[0226] To improve the "mottled" appearance of composites, it is often desirable for fibrous materials to have a relatively large percentage of fibers over 2.5 mm in length. For example, at least 2.5 percent

EP 1 877 192 B9 by weight of the fibrous material are fibers having a length greater than 2.5 mm, for example at least 5.0 percent by weight of the fibrous material are fibers having a length greater than 2.5 mm, at least 7.5 percent by weight of the fibrous material are fibers having a length greater than 2.5 mm or at least 10.0 weight percent of the fibrous material are fibers having a length greater than 2.5 mm. In each of these cases, for example, in order not to adversely affect processability, less than 25 weight percent of fibrous material are fibers having a length greater than 2.5 mm. [0227] In the case of an opaque or translucent resin material, the composite may contain, for example, above 20 percent by weight of fibrous material, e.g. above 30 percent, above 40 percent, above 50 percent, above 55 percent or even above 60 weight of fibrous material . For any of the embodiments in this paragraph, the composites generally contain less than 70 percent by weight of fibrous material.

[0228] If desired, the fibrous material can be dyed, for example, to improve the strength of the visual effect. The fibrous material can be dyed, for example, by dyeing prior to combining with the resin to form composites. In some embodiments, this dyeing can, for example, improve the visibility of the fibrous material in the outer surface, especially large clusters of fibrous material.

[0229] In some embodiments, the resin may be stained, for example, with a pigment or dye to improve the contrast between the fibrous material (colored or natural) and the resin, for example, to improve the overall strength of the visual effect. Coloring concentrates are available from Clariant.

[0230] Any of these composites having certain visual attributes may include any of the flavoring additives described herein.

[0231] Various shapes can be formed from the composite, such as those described above.

[0232] When the composites are injection molded, it is often desirable to quickly "freeze" the molten resin, for example, by molding the composite with a relatively cool mold surface so that there is no time to "sink" the fibers under the resin surface where they would be invisible. Regarding Fig. 31A-31C, "mottled" composites can be obtained by making composite 600 by pressing molten resin with a mold 602 having a cooled surface 604, and then removing the formed composite 600. In some embodiments, the pressing is carried out with a mold surface having a temperature below 100 ° C, for example below 75 ° C, below 50 ° C, below 25 ° C or below 15 ° C. [0233] Still other composites having unique, pleasant or even striking visual features and desirable mechanical properties include transparent resin and fibrous material. In some embodiments, the fibrous material is visible in the composite. Generally, to make such composites, the transparent resin and fibrous material are combined to provide a transparent resin / fibrous material combination and the transparent resin / fibrous material combination is pressed, for example, in an extruder or in a mold to make a composite.

[0234] The resin may be thermoplastic or thermoset. The thermoplastic resin may be, for example, a clear polyolefin, such as clear polypropylene (e.g. polypropylene copolymer); polyester such as polyethylene terephthalate (PET); amorphous polyamide; polycarbonate; a styrene polymer such as a styrene-acrylonitrile (SAN) copolymer; polyacrylate, such as poly (methyl methacrylate) (PMMA).

_® [0235] Clarifying agents for polyolefins are available from Milliken Chemical under the trade name MILLAD^®on _® MILLAD example^® 3988. Clear polyolefin coloring agents are also available from Milliken Chemical _® under the trade name CLEARTINT^®.

[0236] In order to increase the effect obtained when using transparent resin, it is often desirable for the resin to have a transmittance above 60 percent, for example above 65 percent, above 70 percent, above 75 percent, above 80 percent, above 85 percent or even above 90 percent. In addition, it is often desirable for the resin to have haze of less than 40 percent, e.g., less than 35 percent, less than 30 percent, less than 25 percent, less than 20 percent, less than 15 percent, or even less than 10 percent. Both transmittance and haze are measured using ASTM D1003-92, which is fully incorporated herein by reference.

[0237] In order to increase the effect obtained when using transparent resin, it is often desirable for the composite to have a relatively low content of fibrous material, for example less than about 20 percent by weight of the fibrous material, less than 17.5 percent, less than 15 percent, less less than 12.5 percent, less than 10 percent, less than 7.5 percent, less than 5 percent, less than 2.5 percent, or even less than 1 percent by weight of fibrous material. The relatively low fiber content allows light to pass through the composite, so that a large amount of fibrous material is visible inside the composite. [0238] Referring to Fig. 32, the resin / fibrous material composite may have an inner portion 610 that includes a first resin essentially free of fibrous material, and an outer portion 612 that includes a second resin that surrounds the inner portion and includes substantially all of the fibrous material . Such a composite can be made, for example, by co-molding or co-extrusion. Any of the fibrous materials or additives described above can be used to make such a composite. Any of the shapes described above can be formed from such composites. The first and second materials may be the same or different and may be, for example, any of the resins described above.

[0239] Referring to Fig. 33, the transparent resin / fibrous material composite may have an inner portion 620 including the first resin and containing substantially all fibrous material and an outer portion 622 surrounding the inner portion comprising the second resin and substantially no fibrous material. Any of the fibrous materials or additives described above can be used to make such a composite. Any of the shapes described above can be formed from such composites. The first and second materials may be the same or different and may be, for example, any of the resins described above.