Insulating partition comprising cellulose and adapted cellulosic material

0001Insulating partition comprising cellulose and adapted cellulosic material

0002The present invention relates to an acoustic insulation wall. It has applications in the construction and layout of buildings. The invention also relates to a cellulosic material adapted to the partition.

0003Here is meant the term wall as corresponding to any type of wall. It can be either an interior separation, or more rarely an outer wall.

0004In addition to regulations concerning safety, fire protection in particular, acoustic regulations are in force today. Tests are defined in particular to measure the transmission of noise from one room to another. The measured noise level must be below a certain threshold for the construction to be put on the market.

0005The sound insulation can be obtained by the use of a solid masonry element of the structural type which has a large surface area. Sound insulation can also be obtained by the use of so-called "mass-spring-mass" systems in which two walls, which are substantially rigid but of reduced thickness, are separated by a space called the building void and which can be filled with a absorbent material by porosity and / or resonance. In the following we will use the generic term of absorbent material. This type of partition will be called later lightweight partition and is the object of the present invention. Lightweight partitions can be used vertically or horizontally depending on the desired application. On the other hand, in some applications one of the two walls substantially rigid can be replaced by a structural work of the type wall, floor or ceiling.

0006In vertical applications, lightweight partitions are used both for the construction of partition walls and for partition walls. On the other hand, it is also possible to make modular partitions, that is to say that allow to change the distribution of spaces relatively easily. In practice, partition walls can not be modulated.

0007A lightweight partition is generally made of a frame which is secured to the shell and on which are fixed, parallel to each other, two substantially rigid walls with siding. Each of the walls is generally made of a rectangular siding of standard size and based on plaster or wood. The siding is generally arranged horizontally small so that it is continuous between the floor and the ceiling in the direction of the height, at least in applications with a ceiling height less than or equal to the length of the facings. It is also possible to improve the insulation characteristics of the partition by implementing thicker walls. For this purpose it is possible to join two or more standard thickness patches to form each of the walls.

0008The frame may be metallic and then comprises elements called rails which are horizontal and placed on the floor and ceiling and elements called uprights which are vertical and arranged between the rails at regular intervals which are generally related to the width of the rails. facings forming the walls. In the case of rails, furs and metal uprights, they are U-shaped or even H depending on the applications. In some applications, the frame may be of wood.

0009In the following will be called amount an element of the frame which is vertical in the case of a vertical partition and more generally which is arranged parallel to the largest side length of the wall facings. Similarly rail will be called an element of the frame that is perpendicular or substantially perpendicular to the uprights. The frame having a certain thickness, a construction gap is created between the two walls. This building void is generally filled with an absorbent material generally of the mineral wool type or sometimes wood fiber, to improve the insulation characteristics of the partition. The present invention, which proposes an alternative solution that can be used vertically as well as horizontally, relates to an acoustic insulation partition comprising:

0010- a frame composed of rails and uprights (also called furs)

0011two walls each comprising at least one substantially rigid facing,

0012at least one thickness of a fibrous material, the walls being arranged substantially parallel at a distance [between them and fixed on the framework by fastening means in order to define internally a transverse width construction void [in which is disposed the fibrous material.

0013According to the invention, the fibrous material is a self-supporting, substantially homogeneous rectangular cellulosic mat having a density of between 200 and 800 kg / m.³ , said mattress being constituted, essentially, fiber from the treatment of recycled paper and paperboard and practically free of lignin, the connection between the fibers within the mat is obtained at least partly during the manufacture of the mattress wet, said mat having a thickness e such that e <1 so that the mattress is substantially not compressed between the two walls, the acoustic insulation supply index due to the absorbent inside said partition called ΔR and measured according to NF EN ISO 140-1, 143-3, NF EN 20140-2 and ISO 717/1, being at least 2 dB.

0014The term self-supporting means that the mattress is rigid enough not to collapse or collapse under the effect of its own weight. The homogeneous term means that the fibrous material constituting the mattress is distributed substantially uniformly in the thickness and throughout the mattress.

0015In various embodiments of the invention, the following means can be used in isolation or in any technically possible combination are implemented:

0016the thickness e of the absorbent pad is between 1 mm and 5 mm and is preferably approximately 3 mm,

0017- The mattress is substantially flat, - the mattress has periodic folds of the kind waves or ribs,

0018the peak-to-peak amplitude has folds between 20 mm and 100 mm with a <[so that the mattress is not substantially compressed between the two walls,

0019the periodicity of the folds is between 40 and 600 mm,

0020- In the case of a mattress with folds of the kind undulations, the corrugations are sin usoidal,

0021- In the case of a mattress with folds of the kind undulations, the corrugations are sawtooth symmetrical or not,

0022in the case of a mattress comprising folds of the vein type, the ribs are symmetrical or non-symmetrical crenellations,

0023the folds are in a direction parallel to the long side of the mattress,

0024the folds are in a direction perpendicular to the long side of the mattress,

0025- the mattress is inserted into the frame,

0026the mattress is interposed between the framework and at least one of the two walls, in order to acoustically decouple said wall from said framework,

0027the mattress is interposed between an amount of the frame and at least one of the two walls in order to acoustically decouple said wall from said upright, the mattress is interposed between a rail of the frame and at least one of the two walls for acoustically decoupling said wall of said rail,

0028the mattress comprises a binder,

0029the mattress comprises a swelling agent; the swelling agent is an alkylene oxide;

0030the blowing agent is dosed up to 0.5% of active product relative to the dry fiber,

0031the mattress comprises at least one additive chosen from antifers, products against moisture uptake, wet strength products, products against rot and products against molds, fire-fighting agents are chosen from derivatives of halogenated products,

0032the anti-fires are chosen from boron derivatives,

0033the boron derivatives are boric acid and / or boron salts and / or phosphate salts, the product against moisture uptake is a synthetic bonding polymer,

0034the product against moisture uptake is dosed between 0.25% and 0.5% of active product relative to the dry fiber,

0035the product of resistance in the wet state is an amino-polyamide epichlorohydrin resin,

0036the product of resistance in the wet state is dosed up to 3% of active product relative to the dry fiber and is preferably dosed at 0.4%,

0037- The charge rate is advantageously less than 20%, - the mattress is perforated by openings,

0038the openings are circular,

0039- the openings are oval,

0040the average diameter of the openings is between 4 mm and 10 mm, the perforation rate measured by the ratio of the total area of ​​openings to the total area of ​​the mattress is less than 20%,

0041- In the case of a mattress with folds, the openings are arranged on the sides of the corrugations or ribs,

0042- only one mattress is used in the building vacuum, - u first wall corresponds to a structural masonry element of the wall type, floor or ceiling, the mattress then being placed in the building void defined between the masonry element and the second wall, (the term masonry covers both a structural work and plastering) - the mattress is obtained by suction on a felt and then forming a cellulosic pulp made by recycling cellulosic materials obtained by defibration of paper or cardboard recovery.

0043In the most general case of a vertical partition with vertical uprights and horizontal rails in which the wall facings are arranged vertically resting on the ground by their width, the amounts of the frame are related to the length of the / of the facing forming the walls. In some other applications where the ceiling height is smaller, attic for example, the facings may be arranged horizontally and the vertical uprights are then related to the width of the siding / s.

0044The present invention also relates to a fibrous material for use in an acoustic insulation partition comprising a framework, two walls each comprising at least one substantially rigid facing, at least one thickness of a fibrous material, the walls being arranged substantially parallel at a distance [between them and fixed to the framework by fastening means to define internally a transverse width construction void [in which the fibrous material is disposed.

0045According to the invention, the fibrous material is a cellulosic mat according to any one of the preceding characteristics and possibly combined.

0046The invention therefore uses a mat made by wet recycling of cellulosic materials from paper or cardboard recovery. The term recovery paper covers any product that was originally manufactured from paper pulp using a paper-making process of the mechanical, thermochemical or chemical kind and, for example, newsprint, cardboard, cellulosic packaging. . Cellulosic materials that are crushed for mattress production may therefore come from paper already recycled during several recycling cycles or from paper produced from a virgin pulp produced from wood most commonly other plants, straw for example. These materials may therefore have different characteristics depending on their origin and it is thus possible to modify the characteristics of the mattress by selecting and combining recovery papers of different origins. It can be seen that paper from a virgin pulp may have fibers of an average length greater than those of paper having undergone several recycling operations. Thus, the cellulosic fibers obtained by recycling fibers obtained initially by a papermaking process measure on average approximately 0.9 to 3 mm long and 10 to 50 μm wide. The present invention will be better understood by reading an example of implementation of the invention where:

0047- Figures 1 and 2 show a schematic front view of a partition;

0048FIG. 3 represents a vertical section of a partition at the level of an upright;

0049- Figure 4 shows a horizontal section of a wall at an amount;

0050- Figures 5, 6 and 7 represent acoustic decoupling methods. The example of partition 1 of the vertical wall type and shown in the figures is made from a metal frame 2 which comprises rails 21 at ground level and the ceiling and uprights 22 arranged substantially vertically between said rails. The two walls 31, 32 which are implemented in this partition are made by edge-to-edge assembly of standardized size rectangular plates or plates which can be cut to size and are, for example plaster-based plates. In some other applications the framework and / or the facings are wood. In Figure 1, the first wall which is on the side of the observer is not shown so that the frame 2, the building void and the second wall 32 are visible. The spacing between the amounts is a function of the required mechanical performance. In this example with a metal frame, the periodicity O_p of installation of the amounts is about 60 cm (O_p = 60 cm). Since the uprights and the rails are generally U-shaped profiles, the width of the free space Oj of the construction gap between and outside the uprights is less than 600 mm (Oj = 53 cm). This structure shows three alternative embodiments of a self-supporting, substantially homogeneous cellulosic rectangular mattress 4 with a density of between 200 and 800 kg / m.³ said mattress consisting essentially of fibers from the treatment of recycled and substantially lignin-free paper and / or paperboard, the bond between the fibers within the mat being obtained at least in part during manufacture of the wet mattress. In the first two variants, the mattress comprises periodic folds of the kind undulations or ribs whose directions are either perpendicular or parallel to the long side or length of the mattress. In the first variant, the folds of the mattress 41 are horizontal, that is to say that the folds are arranged in a direction perpendicular to the uprights. In the second variant, the folds of the mattress 42 are vertical, that is to say that the folds are arranged in a direction parallel to the uprights. In the third variant the mattress 43 is substantially planar. 1, the mattresses 41, 42 and 43 have a length L of about 249 cm (ML = 249 cm) and a width M | about 58 cm (M | = 58 cm). The dimension Mi is larger than the dimension Oj because when the mattress is disposed in the building gap, it engages in part by one or preferably two of its edges along its length in the female part of a post 22 like this will be explained in connection with the following figures. This engagement of the edges of the mattress is shown in Figure 1 by dashed lines. Note that in addition to the length, a commitment of a mattress edge 41, 42, 43 over the width is also possible with the rails 21, ie at the bottom or at the top or bottom and up.

0051Although the mattress is self-supporting, that is to say it is rigid enough not to collapse on itself, this rigidity is not absolute, and it has a relative flexibility to deform temporarily , or definitively depending on the case, during installation and, in particular, to be able to slide its edges length and / or. width in the elements of the frame 2, whether the rails 21 and / or the uprights 22.

0052In Figure 2, the observer-facing wall has not been shown and all of the building voids have received rectangular mattresses of the parallel-fold type on the long side. The mattresses that are used in this example initially measure 166 cm long and 58 cm wide. The height of the partition being 249 cm, a complete mattress 41 has 166 cm and a portion 41 b of mattress cut to 83 cm in length must be associated in each building void between two adjacent amounts. On the other hand, the building vacuum at the right end of the partition being narrower than the others, the mattresses 41 'a and 41' b which are placed there are also cut across the width.

0053The dimensions indicated are illustrative and the implementation of the invention with other dimensions is contemplated. Thus, mattresses 2.49 m long and 0.6 m wide or 1.66 m by 0.6 m are also produced, whether flat or corrugated mattresses in the length or width direction. . These latter dimensions allow the use of mattresses in walls of the most common type of 2.5 m in height and with a center distance of 0.6 m between uprights.

0054In FIG. 3, the partition is viewed transversely and in vertical section at a rail 21 which is a U-shaped metal section on which the two walls 31 and 32 are fixed, for example by screws 5. Inside the construction gap is disposed the first variant 41 of the mattress, so with horizontal folds. When placing the mattress in the building vacuum, its edges are introduced into the female part of the uprights. In this example, the peak-to-peak amplitude of the folds is such that the mattress is held in the rail 21 without being substantially compressed by the walls 31 and 32. However, it is also possible that the maintenance of the mattress is obtained by fixing on the rail, associated or not with the maintenance by folds. The amplitude of the corrugations or ribs of the mattress which corresponds to the peak-to-peak distance in the direction of the thickness of the partition is a function of the width of the building gap so that the mattress is substantially free in the thickness of said space. Although the mattress is substantially not compressed between the two walls, it can however be supported on the latter. In FIG. 4, the partition is seen in horizontal section at an upright 22 on which the two walls 31 and 32 are fixed, for example by screws 5. The walls 31 and 32 are made by edge-to-edge assembly which join at the uprights. Inside the building gap is arranged the second variant 42 of the mattress with vertical folds. In this example, the peak-to-peak amplitude of the folds is such that the mattress is held in the upright 22 without being substantially compressed by the walls 31 and 32. However, it is also possible that the maintenance of the mattress is obtained by fixing on the amount, associated or not with the maintenance by folds. The dimensions indicated in FIGS. 1 to 4 are purely indicative and correspond to standard values ​​in the field and other dimensions as well as other laying methods are envisaged. In another embodiment of the mattress, not shown in FIGS. 1 to 4, the latter is substantially plane,

0055In the context of the implementation of the invention is also envisaged a reinforced partition, that is to say whose walls have been "increased" by implementation of a superposition of facings, usually two adjoining siding, for each of the walls. In a preferred manner, these facings are offset between them, which requires the use of a larger number of amounts because the facings are fixed at their edges on the framework.

0056In FIG. 5 showing a partition in vertical cross-section, a planar mattress 4 is placed in the building void created by the walls 31 and 32, the rails 21 on the floor and on the ceiling 6 and the uprights (not shown). The walls 31 and 32 are fixed along their edges along the length and the width to the framework by screws 5. In order to strengthen the partition, additional amounts are here implemented. In order to acoustically decouple the walls of the framework, the mattress is interposed between the latter and the rails 21. A damper is made between the wall plate and the frame. As indicated above, the mattress has a relative flexibility, which allows it to deform to decouple alternately one 31 then the other 32 wall. Since the figures are not to scale, the deformations are in fact distributed relatively large distances relative to the thickness of the mattress. This distance corresponds approximately to the height of the partition. Figure 6 is an alternative embodiment of the assembly of Figure 5 where a greater decoupling is obtained by interposition of the mattress along the edges of the partition walls.

0057On FIG. 7, showing a partition in horizontal section, a plane mat 4 is placed in the building void created by the walls 31 and 32, rails (not shown) and posts 22. The walls 31 and 32 are fixed along their edges along the length and the width to the framework by screws 5. In order to strengthen the partition, additional amounts are here implemented. In order to acoustically decouple the walls of the framework, the mattress is interposed between the latter and the uprights 22. As indicated above, the mattress has a relative flexibility, which allows it to deform to decouple alternately one 31 then the other 32 wall. Since the figures are not to scale, the deformations are in fact distributed relatively large distances relative to the thickness of the mattress. The installation of the mattress in the female parts of the frame can be associated with the decoupling, the latter being then possible only at the end not engaged in the female part of the frame. Preferably, the wall (s) are acoustically cut so that, on the one hand, the adjacent walls of the same wall remain aligned without recess and, on the other hand, that the two walls remain substantially parallel to each other.

0058Figures 5 to 7 show a planar mattress. However, it is contemplated the implementation of a mattress having folds in an assembly with acoustic decoupling. In the context of this invention, the fibrous material mattress made of cellulose can be made in various functional forms.

0059The acoustic insulation capacity of the partition comprising the mattress can be explained by the fact that the latter, in addition to its absorption capacities, works at least in certain frequency ranges as a resonator and thus dissipates acoustic energy. .

0060It appears that the acoustic absorption depends on the interaction between the fibers and the air around them. This absorption is a function of the porosity of the fibrous mat. The mattress of the invention uses a material of high porosity and preferably greater than or equal to 50. The density of the cellulosic material of the mattress is preferably between 200 and 800 kg / m.³. In a preferred embodiment, the mattress is regularly perforated by openings. These regular perforations have a positive effect on the insulation capacity of the partition. A perforation rate measured by the ratio of the total surface area of ​​the apertures to the total area of ​​the mattress of less than 20% makes it possible to obtain interesting results.

0061The mattress is made wet by using cellulose pulp obtained from recycled paper and / or cardboard and which preferably comprises a blowing agent for increasing its own volume and a binder for increasing its mechanical strength. clean in the wet state. However, the connection between the fibers within the mattress is obtained at least in part during the manufacture of the wet mattress because the cellulose mattress comprises fibers of various sizes and in particular poorly oriented whose entanglement ensures cohesion from the whole.

0062Moreover, in order to increase the resistance to fire and the environment, anti-fire and anti-moisture agents are preferably incorporated in said mattress. Antifoam agents are for example based on boron. The anti-humidity agents are products against the absorption of moisture and for example synthetic polymers for bonding. The mattress may also include various loads from the paper or cardboard recovery that are triturated.

0063In a particular embodiment, cellulose is used which, in the dry state, has a density of approximately 0.6. This type of cellulose is essentially obtained in four steps: pulping, grinding of paper or cardboard recovery in an aqueous mixture comprising about 15% cellulose and 85% water;

0064- Dilution of the pulp to obtain a concentration of about 1% cellulose, or 99% water;

0065- formation of the mattress by suction on filter or felt;

0066- drying.

0067In detail, the process used for producing the mattress is as follows: A preparation is obtained by defibrating the waste paper in the water using a "hydra-pulper".

0068Old paper or cardboard is the basic raw material. They are usually delivered in compressed bales.

0069Specific unloading equipment is recommended. The storage in a particular hall and the feeding of the "hydra-pulper" are carried out by a lift truck equipped with tongs.

0070The preparation is carried out with recycled water from a storage tank. In this first phase of manufacture, a large amount of water is needed. The use of recycled water avoids excessive consumption.

0071However, some fresh water is needed to compensate for losses due mainly to evaporation in the dryer.

0072The action of "hydra-pulper" is completed by those of ancillary equipment, which allow the purification of the preparation and its dilution to the required concentration.

0073The manufacture of the mattress is to eliminate, in stages and under specific conditions, the water contained in the preparation until the mattress has sufficient cohesion. This elimination begins with a gravity desegutting, then a forced suction éévuttage, then by the combined actions of a suction and a possible pressing and finally by evaporation in a furnace-tunnel.

0074The preparation from a storage tank at the required concentration is poured on a horizontal felt through a dispenser to form the mattress. This felt, stretched, scrolls at adjustable speed.

0075The dispenser whose flow is adjustable, allows to vary the thickness of the mattress. The felt carrying the mattress first passes on crates of gravity dripping, then on vacuum crates.

0076The water collected in these boxes, is evacuated in a vat of storage for its reuse.

0077At the exit of the vacuum crates, a canvas unfolds on the upper part of the mattress. The set consisting of top to bottom, canvas, mattress and felt is introduced into the section of the presses. Water discharged by the combined action of pressure and vacuum is collected and stored for reuse. However, so that the mattress has sufficient porosity, the pressure exerted by the press is reduced, or even in a preferred mode, no pressing is carried out, the water then being essentially eliminated by the action of the vacuum.

0078At the exit of the previous step, the mattress is sufficiently substantial so that it can be conveyed without support. Circular side knives cut to the required size.

0079After this operation and in the case where it is desired to make a mattress with folds, the mattress is corrugated between an undulator and the dryer tube conveyor. If necessary, perforations and mechanical pre-cutting and / or water jet can be performed.

0080The next operation is to remove water remaining in the mattress by evaporation. For this, it is conveyed by a conveyor through a dryer. The dryer is composed of several identical zones juxtaposed. In each zone a generator produces hot air that is blown on each side of the mattress.

0081The invention is applicable to partitions of the distribution or modular type, separative and partitions, part of which consists of a masonry element corresponding to the shell. It is thus contemplated in the context of the invention that one of the walls is a wall, floor or ceiling made of concrete or any other structural construction material.

0082The examples of implementation given are only indicative and can not limit the scope of the invention. In particular, the term "corrugation" or "rib" corresponds to the forms described as well as to forms of the sinusoidal, crenellated, triangular, trapezoidal type. Similarly, it can be implemented a substantially flat mattress in the partition.