Mechanical tab fastener element and process for producing thereof

06/17/92 (71) The Procter and Gamble. Cineinnati. Ohio, US (72) Thomas Dennis Albert, Cineinnati, Ohio, US

Ooulait David Joseph Kenneth, Cineinnati, Ohio. US (54) Mechanical clip and method of its production

The recesses (22) are formed by depositing heated heat-sensitive material on a substrate (24) which is conveyed at different speeds relative to the heated material applied to the substrate (? 4) in the form of a recess. The conveyed substrate (24) can be towed away from the storage point at a deflection angle. By varying the speed difference between the substrate (24) and the heated heat-sensitive material. when it is stored. by varying the angle between the substrate (24) and the point of deposition of the heated heat-sensitive material, the fastening properties preferably change. in particular the shear strength of the fastening system (20) formed from these recesses (22). The recess (22) includes a shaft (28) connected to the substrate (24) in the base (26), having a proximal end adjacent said base (26) and extending outwardly from the substrate (24) at an angle to the substrate (24). (28) is terminated by a catch means (30).

running to the side behind. the circumference of said shaft (28). The catch means (30) is intended to penetrate the opposite receiving surface of the fastening system (20) and to catch behind the strands or fibers of the material of this receiving system.^r areas.

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Field of technology

The invention relates to fasteners._w Mechanical fastening systems and in particular a method of manufacturing a fastening system having improved design and fastening properties.

State of the art

Resealable mechanical fastening systems are well known in the art, typically such fastening systems include two main components, namely a protrusion which is attached to the substrate and captures an additional second component, i.e. the receiving surface. typically contains one or more layers of strands or fibers,

The protruding portion of the protrusion of the mechanical fastening system, typically referred to as the securing means, penetrates the receiving surface and catches the strands or fibers of the receiving surface. The resulting mechanical grip and physical obstacles prevent the protrusion from being removed from the receiving surface until the separating forces exceed the peel strength or shear strength of the fastening system.

In many applications, the shear strength of the fastening system becomes important (if not critical) and the designer may want to tailor the shear strength of the mechanical fastening system to the desired application. fixed according to the needs of such use.

For example, reusable mechanical fastening systems can be used in conjunction with post-use absorbent articles such as diapers. U.S. Patent No. 4,846,815 discloses a diaper having a resealable fastener that provides resistance to common shear and which is comfortable and gentle on the skin of the person wearing it. U.S. Pat. 4 U.S. Pat. was polluted.

Li If a mechanical reclosing fastening system is used in conjunction with an absorbent article for ejection after use, such as a diaper, a certain minimum shear strength is required to minimize the possibility of the mechanical fastening system disengaging during wear._r so as to allow the fabric to separate or fall off the wearer. This phenomenon increases the likelihood that the absorbent article will not properly capture body exudates to be absorbed by it.

Li If the absorbent article is an incontinence protection device for adults, reclosing systems may also be advantageously used, as described in U.S. Patent No. 07 / 382,157 of 1607.

1969 /. In contrast to the need for fastening systems to have a certain minimum shear strength, as described in the document, the adult incinement product may be required to have only a certain maximum shear strength. The difference is that the wearer may have limited manual force or dexterity, and if the shear strength of the fastening system is too great, the wearer may not be able to remove the absorbent article as needed after use to inspect whether it is soiled or to routinely replace the article.

Rain in another application, it may be desirable to have a mechanical fastening system that allows some slip of the protrusion relative to the receiving surface in a direction generally parallel to the plane of the receiving surface and the direction in which the fastening engagement is desired. Such a side sliding creates a fastening system which is somewhat adjustable in the relative position of the protrusions on the receiving surface when the two components are fastened to each other.

Other properties, such as structural properties or the geometry of mechanical fastening systems, can also be significant. The person skilled in the art may also wish to adjust these properties to the requirements. , in which to adjust these properties of the fastening system in proportion to the strength of the layers and fibers or strands of the receiving surface and the required shear strength of the fastening system ·

In particular, it has been found that there is some relationship with the angles formed by the protrusions with respect to the plane of the substrate and the shear strength of the fastening system. For a longer time, there has been a relationship between certain parameters of the production process and the angles formed by the protrusions resulting from such processes.

It is therefore an object of the invention to provide a method for suitably adjusting the fastening properties, in particular the shear strength of mechanical fastening projections, when the mechanical fastening system is produced. It is also an object of the invention to provide a method of adjusting the lateral run-out of mechanical fastening protrusions and the angles formed by the mechanical fastening protrusions relative to the substrate during manufacture of the mechanical fastening system. Finally, it is an object of the invention to provide a mechanical fastening protrusion which can slide laterally in a direction parallel to the plane at the collecting surface after it has been caught and as long as the fastening projection and the receiving surface are fastened to one another.

Characteristics of the invention

The essence of the invention is a fastening system of mechanical protrusions, which can be switched on again, for connection to an additional receiving surface, and a method of manufacturing such a fastening system. The protrusions of the reclosing fastening system have a base and at least one loosely shaped protrusion comprising a base, a shaft and a catch means. The base of the protrusion is attached to the base and the shaft abuts the base and extends outwardly therefrom. The locking means is connected to the shaft and extends to the side beyond the circumference of the shaft.

- 4 The fastening system can be designed in a way that. a heat-sensitive material is used which is heated to the melting point.

The substrate is conveyed in the first direction at a first speed relative to the depositing means. · Discontinuous amounts of heat-sensitive material are deposited in the second direction on the conveyed substrate. The substrate is pulled away from the storage means at an obtuse angle and defined in the first and second directions.

In a different embodiment, the method for manufacturing the mechanical fastening system increases the shear strength of the mechanical fastening protrusion. This process involves the processes of conveying the heated, heat-sensitive material and the substrate to each other. Discontinuous amounts of heated material and substrate relative to each other. Discontinuous amounts of heated heat-sensitive material are deposited on the substrate. such that there is a positive rate difference between the conveyed substrate and the heated heat-sensitive material.

These processes can be advantageously performed using a printing cylinder having a plurality of cells arranged around its circumference. The heated heat-sensitive material is stored in. cells. The printing roller rotates axially about its axis and the substrate is conveyed in the first direction and at the first contact speed; with cells · The heated heat-sensitive material is then deposited from the cells onto the substrate »

If necessary, it can be stored next to the platen. support roller for defining the slot and the clamping plane · The substrate is conveyed through the clamping slot in contact with the cells of the printing cylinder. The substrate is pulled away from the slot at a predetermined sharp angle with respect to the clamping plane. The substrate can be pulled through the slit at a speed that generally; is different from the circumferential speed of the platen.

In a method for increasing the shear strength of mechanical

When the above-mentioned slots and roller structures are used, this device defines an acute angle between the substrate and the clamping plane in the drawings.

The invention is explained in more detail in the following description of exemplary embodiments without limiting its scope, with reference to the accompanying drawings, in which FIG. can be used for the production of a protrusion of the fastening system according to the invention, FIG. 3 graphical representation of the effect of the speed difference between the conveyed substrate and the storage means on the gripping angle of the protrusion shaft for two different angles between the substrate and the clamping plane, Fig. 4 clamping plane, fig. 5 Fig. 6A and 6B are schematic representations of two protrusions made according to the invention, each having the same speed difference between the conveyed substrate and the printing cylinder and having different angles formed between the conveyed substrate and the clamping plane of the device of FIG. 2, FIG. 7A and 7B are schematic representations of two protrusions according to the invention each having the same positive speed difference between the conveyed substrate and the printing cylinder and having different angles between the conveyed substrate and the clamping plane of the slot of the device of FIG. of the invention each having the same angle formed between the conveyed substrates and the plane of clamping of the slit of the device according to FIG. 2 and having different positive speed differences between the conveyor substrate and the printing roller, and Figs. 9A and 9B are schematic representations of two protrusions according to the invention each having a negative speed difference between the conveyed substrate and

by a printing cylinder and having different angles formed between the conveyed substrate and the clamping plane of the slot of the device of FIG.

2.

The present invention

The fastening system of the present invention includes at least one protrusion 22 as shown in FIG. 1 and preferably a group of protrusions 22. Each protrusion 22 may be attached to the substrate 24 in a predetermined combination. Each of the protrusions 22 has a base 26, a shaft 28 and a catch means 30. The base 26 of the protrusions 22 are in contact with each other and are connected to the substrate; 24 and support the proximal ends of the stems 28. The stems 28 project outwards from the base 24 and the bases 36. The stems 28 terminate at a distal end which is connected to the retaining means JO.

The catch means 30 protrudes radially to the side from the shaft 28 in one or more directions and may resemble a hook-like theme. The term "lateral" as used herein means a vector component generally parallel to the plane of the substrate 24 at the main protrusion 22. The catch means 30 is engaged and preferably abuts the distal end of the protrusion 22. It will be; It can be seen that the catch means 10 can be connected to the protrusion 22 at a position between the base 26 and the distal end of the shaft 28.

As shown in Fig. 2, the array of protrusions 22 is formed by any suitable apparatus and method, including methods including a loosely shaped protrusion 22, as described below. The term "free-form" as used herein means a structure that is not removed from the mold cavity or extrusion die in a fixed or defined shape. The protrusions 22 are deposited on the substrate 24 in a molten, and preferably liquid, state and solidify by cooling and preferably quenching to achieve the desired structure and shape, as described below.

The loosely shaped protrusion 22 or array of protrusions 22 may

In this method, a generally planar substrate 24 having two opposing surfaces is passed through a nip of two generally cylindrical cylinders, namely a printing cylinder. J2 and the support roller 74, as shown in FIG. The rollers 72 and have generally parallel center lines and are maintained in contact with the substrate 24 as the substrate passes through the slot 70. the desired combination of protrusions 22 to be deposited on the substrate 24. The second roller, referred to as the support roller 74, provides support and response to the printing roller 72.^r0 depositing the substrate 24 with respect to the printing cylinder J2 as the substrate 24 passes through the slit J0.

The thermally sensitive material, preferably the thermoplastic material from which the protrusions 22 are to be formed, is provided from a heated source, such as a chute. The heat sensitive material is heated, preferably to at least the melting point. The heat-sensitive material is introduced into the cells J6 as the printing roller J2 rotates about the centerline. The cells J6 containing the heat-sensitive material transport it until contact with the substrate 24 and the heated, heat-sensitive material is deposited on the substrate 24 in the desired combination.

As the displacement between the substrate 24 and the rollers 72 and 74 continues, the protrusions 22 extend in a direction having a lateral component generally parallel to the plane of the substrate 24, thereby forming a shaft 28 and a catch means 30. Finally, it can. the waste of the protrusion 22 is cut off from the catching means 30 by the cutting means 78. However, the trimming means 18 may be discharged and the protrusion 22 may be separated from its waste without the use of a special trimming means 78, provided that the parameters for which the fastening system 20 is manufactured are suitable for waste disposal without such a special trimming means 78. Due to the viscoelastic properties material, the protrusion 22 contracts under the influence of gravity and shrinkage, which occur during cooling. The protrusion 22 then cools and preferably. - is frozen into a solid structure in which the catch means JQ abuts the shaft 28 »

The fastening system 20- is fastened to an additional receiving surface- Pod. By the receiving surface to which the gripping means JQ of the fastening system 20 is fixed, any plane or surface having an exposed surface with tightly spaced apertures complementary to the gripping means JQ and defined by one or two strands of fibers or alternatively having an exposed surface is defined. which is capable of localized elastic deformation, so that the catch means JQ can remain trapped and cannot be pulled out without collision. Localized elastic deformation openings allow the gripping means JO to enter the plane of the receiving surface, while strands / or undeformed material (receiving surfaces) inserted between the openings / or deformed surfaces prevent the fastening system 20 from being pulled out or released if requested by the user or until peelers or the shear strength of the fastening system 20 is otherwise exceeded. The receiving surface may be planar or curved.

Is the receiving surface having strands or fibers considered? is considered complementary if the openings between the strands or fibers are sized to allow at least one trapping: means JO penetrate into the plane of the receiving surface, and the springs are of such a size that they are captured by the trapping surface! The receiving surface which is locally deformable is said to be complementary if at least one catching means JO is able to cause a local disturbance in the plane of the receiving surface, this disturbance resisting removal or separation of the fastening system 20 from. reception area.

Suitable receiving surfaces include crosslinked foams, knits, nonwovens looped loop materials, such as Velcro OSA from Manchester's Velcro loop materials, vhodné · £ Ε- of Spartaburg, South Carolina, and no.

1611 &amp; from Guilford Mills of Greenstoro, North. Carollna ·.

Referring again to Fig. X to examine the components of the fastening system 20 and the individual protrusions 22 in greater detail, the substrate 26 of the fastening system 20 needs to be strong enough to prevent tearing and separation between the individual protrusions 22 of the fastening system 20. at the same time it needs to be a surface to which the protrusions 22 will easily adhere and be able to be attached to the product to be fastened as required by the user. "Connection term" as used herein means a condition where the first member or component is attached or attached to the second member or component, either directly or indirectly, where the first member or component is attached or attached to. an intermediate member or folder that is itself attached or attached to another member or folder. The association between the first member or component is intended to remain for the life of the subject. Substrate ”is any exposed area to which one or two protrusions 22 are attached.

The substrate 24 should also be able to roll, as well as withstand conventional manufacturing processes, be flexible so that it can be bent to the desired shape, and be able to withstand the heat of the liquid protrusions 22 deposited thereon without melting or melting. adverse effects would occur before the protrusions 22 solidify. Substrate 24 should also be available in various widths. Suitable substrates 24 include knits, woven materials, nonwovens, rubber, and vinyl films, and especially polyolefin films, and preferably kraft paper. White kraft paper having a base p

a weight of 0.08 kg / m was found to be suitable.

The base 26 of the protrusion 22 is generally a planar portion of the protrusion 22 that is attached to the substrate 24 and abuts the proximal end of the protrusion shaft 28. As used herein, the term base refers to that portion of the protrusion 22 that is in direct contact with the substrate 24 and supports the stem 28 of the protrusion 22. It is not necessary to see the interface between the base 26 and the stem 28 of the protrusion 22.

It is only important that the shaft 28 does not separate from the base and the base 26 does not separate from the substrate 24 during use.

The cross-section 26 of the base should provide sufficient structural integrity and thus an area for the required peel strength and shear strength of the fastening system 20, based on the combination density of the protrusions 22 and the length of the stems 28 of the individual protrusions 22 and further to provide adequate adhesion to the substrate 24. longer shaft 28, base 26? should generally have a larger cross-sectional area to ensure sufficient adhesion to the substrate 24 and adequate structural integrity.

The shape of the base 26 on the substrate 24 is not important and can be expanded in any direction to provide greater structural integrity and thus greater resistance to peeling in that direction. The term heel here means the contact surface of the base 26 on the base 24. The aspect ratio of the heel should not be too large, otherwise the protrusion 22 may become unstable when subjected to forces parallel to the shorter side of the heel. A ratio of less than about 1.5 .mu.l is considered suitable and a circular heel is generally considered more preferred.

A base 26 having a heel of generally circular cross-section and a diameter of about 0.76 is suitable for the embodiment described herein. up to 1.27 mm. If it is desired to provide a fastening system / 20 having greater peel or shear strength in a particular direction, the cross-sectional area of ​​the base 26 can be changed to expand in that direction so that strength and structural integrity perpendicular to that direction increase. This variation causes the protrusions 22 to be thicker when pulled in the extended direction of the base 26.

The shaft 28 abuts the base 26 and extends outwards from the base 26 and the substrate. βθ from substrate 24. As used herein, the term longitudinal means a direction having a vector component away from the substrate 24, which direction increases the perpendicular distance to the plane of the substrate 24 at the base 26 of the protrusion 22, unless otherwise specified. ; substrate 24 »

A stem 26 is associated with the shaft 28 and the base 26 of each protrusion 22. »Origin *¹ of the shank 2S is a point which can be considered as the center of the base 26 and is typically located inside the base of the base 26. The origin j6 is visible when looking at the protrusion 22 from the side. A side view is a view in any direction directed radially to the shaft and base: 26, which is also parallel to the plane of the substrate 26. If the fastening system is manufactured according to the procedure described below, it is preferred, but not necessary, that the view of the protrusion 22 be guided in the machine direction relative to the path of the substrate 24 through the slit 70. base for the particular side view considered, and this distance is halved to obtain the center of the base for such a view. minor failures - continuities / such as roughness transitions resulting from the connection to the substrate 24 / are not taken into account. This point is the beginning of ^ 6 of shaft 28.

The shaft 28 forms an angle 4-with the plane of the substrate 24. The term plane of the substrate here means a flat planar surface of the substrate 24 at the base 26 of the main protrusion 22 considered. determines; as follows »A profile view is shown on the protrusion 22. The profile view of the protrusion 22 is one of two separate side views and is determined as follows. The protrusion 22 is visually inspected from the side views so that the direction having the maximum lateral runout becomes apparent. Lateral runout is the distance in the lateral and parallel directions and the plane of the substrate 24 from the center of the base 26 in such a view, i.e. the beginning 36 of the shaft 28, to the projection of the farthest lateral point on the protrusion visible in such a view when such a point is longitudinally a. projected downwards to the plane of the substrate 24 *

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It will be apparent to those skilled in the art that the maximum lateral protrusion jS is that which corresponds to the greatest distance from the outer circumference of the shaft 28 or gripping means jQ from the opposite side of the base 26. The side view of the protrusion 22 maximizing the lateral protrusion to such a protrusion 22. It will also be apparent to those skilled in the art that if the fastening system 20 is manufactured in the manner described below, the maximum lateral run-out jS is typically parallel to the machine direction and thus the profile view is oriented in the transverse machine direction. The side view shown in FIG.

is one of the profile views of the protrusion 22. It will be further apparent to those skilled in the art that there is another profile view, generally 10, opposite the profile view shown (so that the maximum lateral protrusion is oriented to the left of the viewer). Either of the two profile views is generally equally well suited for the method described below.

The stem 36 is located, as described above, with the protrusion 22 in profile view. While maintaining the shank 22 in profile view, the imaginary cutting plane 4040, generally parallel to the plane of the substrate 24, is then brought into tangential position with the circumference of the protrusion 22 at the point or segment of the protrusion 22 having the greatest perpendicular distance from the plane of the substrate 24. 22 having the highest elevated position. Perpendicular distance from the imaginary cutting plane 40-40 k; the surface of the substrate 24 to which the protrusion bases 26 are connected defines the height of the protrusion 22. The imaginary cutting plane 40Q-4Q is then one quarter of such maximum perpendicular distance closer to the substrate from the point of highest height so that the imaginary cutting plane captures the protrusion 22 in at the height of three quarters of the perpendicular distance from the plane of the ground 24. to the point of the protrusion 22 in the longitudinal direction furthest from the ground 24 ·

The imaginary cutting planes 4Ο-4Ο are then used to determine the three points on the protrusion 22. The first point is the point where the cutting plane captures the leading edge £ 2 of the protrusion 22 and is referred to as 75 0/0 leading point 44. The leading edge "is the vertex -

- 13 water of the shaft 28, which is oriented in the longitudinal direction away from the plane of the substrate 2 ^ · The second point is placed at an angle of 180 ° around the center of the protrusion 22 and is the point where the cutting plane 4θ “4θ captures the trailing edge £ 6 of the protrusion 22 and is referred to as 75 o / o rear point 48. The "rear edge" is the apex of the circumference of the shaft 28, which is longitudinally oriented towards the substrate 24 and is generally located on the opposite side with respect to the front edge 42. The line connecting the two points falls of course to the cutting plane 4 £ “4P-^and O^E bisected to obtain the center point 41 of the imaginary cutting plane 4Ο-4Ο · Then a line is drawn connecting the center point 42 of the imaginary cutting plane 42 “42^with at the beginning jS of the shank 28 at the base 26. The clamped angle cL, which this line defines with respect to the plane of the substrate 24 »Οθ, the angle Λ of the shank 28 from a perpendicular defined by a line situated in any side view joining the center point 47 of the cutting plane and the origin 36. The smallest angle formed with the plane of the substrate 24 when this line is followed in any direction radially to the shaft 28, and in particular to the origin J6, this direction being generally parallel to the plane of the substrate 24 and orthogonal to the perpendicular, is the angle *, the shaft. It should be noted that when the protrusion 22 is observed, approximately in the machine direction, or approximately 180 ° from it *, an angle θL of about 90 ° will be visible. However, as mentioned above, the angle to be measured the angle which deviates the most from the perpendicular and is generally the angle Λ, which is determined by looking at the protrusion 22 from the profile, typically in cross-section, by the machine. angular relationship with respect to this plane to provide the required strength in a particular direction, this direction being generally parallel to the maximum longitudinal extension 38. However, the angle c in the shaft 28 deviates more from the vertical, the more it results in a specific shear strength in the direction of the side.

- 14 ~ ny ·. For the embodiment described herein, the shaft 28 works well at an angle θ between about 30 ° and about 70 °, preferably about 80 °. perpendicular to the base of the substrate 24 / regardless of the lateral orientation / »

The diameter 49 of the gripping means 44 is also measured from a profile point of view. It is the maximum diameter of the bulge near the distal end of the engaging means 50 and is generally perpendicular to the projection of the center line of the shaft 28 and the catch means. what »

Previous measurements are easy to make using the Model 100-00 11 goniometer? from Tame'-Hart, Inc. of Mountain Lake, New Jersey. If more accurate measurements are required, it will be apparent to those skilled in the art that determining the profile view, origin j6, cutting plane 4Ο-4Ο, 75 0/0 points 44, 47 and 48 and angle ck of the shaft 28 can be advantageously made by taking a photograph of the protrusion 22. and deriving from scale from this photograph. The Model 1700 scanning electron microscope from Amray, Inc. was found to be well suited for this purpose. from New Bedford, Massachusetts. If necessary, several photographs can be taken to determine the maximum lateral run-out 25 and any profile view »

The shank 2S should extend in the longitudinal direction from the base 26 to a distance sufficient to provide a distance between the gripping means 30 of the substrate at a height which allows the gripping means to easily catch or engage the strands on the receiving surface. in that it can penetrate deeper into the receiving surface, thereby allowing the trapping means to trap or engage a plurality of strands or fibers. Conversely, the relatively shorter length of the shaft 28 provides the advantage of providing a relatively thicker protrusion 22, but also provides correspondingly less penetration into the receiving surface and may therefore be unsuitable for receiving surfaces such as wool or loosely interwoven materials that have less densely stored strands or fibers.

If a knitted or woven material is used, it is gray.

- a relatively shorter shaft J8 having a longitudinal length from the substrate 24 to the point or with the segment of the highest height position of about 0.5 mm, preferably at least 0.7 mm, is suitable. If a high fluffy material having a specific size greater than about 0.9 mm is used, a relatively longer shaft 28 having a larger longitudinal dimension of at least about 1.2 mm, preferably at least about 2.0 mm, is more suitable. When. the length of the shaft 28 increases and the shear strength decreases accordingly, the density of the protrusions. 22 the fastening system 20 may be raised to compensate for such loss of shear strength.

As described above, the longitudinal length of the shaft 28 determines the longitudinal distance of the gripping means JO from the substrate 24. The longitudinal distance is the smallest perpendicular distance from the plane of the substrate 24 to the circumference of the gripping means JO. For the constant geometry catch means 10, the longitudinal distance of the catch means 10 from the substrate 24 increases with increasing length of the shaft 28 in the longitudinal direction. A longitudinal distance of at least twice the diameter of the strand or fiber of the receiving area, and preferably ten times the diameter of the fiber or strand, provides good grip or engagement and holding of such strands or fibers by the gripping means 10 of the fastening system 20. In this case, the protrusion 20 having a longitudinal spacing of about 0.2 mm to about 0.8 mm works well.

The shape of the shaft 28 is not critical. The shaft 28 can thus have any desired cross-section, according to the above-mentioned parameters relating to the cross-section of the base 26. The cross-section is the planar surface of any part of the protrusion; 22, guided perpendicular to the shaft 28 or the catch means JO. The shaft 28 is preferably chamfered to reduce the cross-sectional area as the distal end of the shaft 28 and the catch means 10 of the protrusion 22 approach in the longitudinal direction and to the side. This arrangement provides a corresponding decrease in the moment of inertia of the shaft 28 and the catch means 30, which results in an almost constant stress as the separation forces are applied to the fastening system 20, thereby reducing the amount of unnecessary materials included in the protrusion 22.

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- 16 To maintain the desired geometry over a wide range of protrusion 22 sizes, it is possible to use a uniform cross-sectional area ratio to scale the protrusions 22. One ratio that typically controls the overall taper of the protrusion 22 is the ratio? the cross-sectional area of ​​the base 26 to the cross-sectional area of ​​the protrusion 22 at the highest position of the protrusion 22. As mentioned above, the term highest position refers to that point or segment of the shaft 28 or gripping means 10 which has the greatest perpendicular distance from the plane of the substrate 24. Typically, the protrusion 22 having a ratio of base cross-sectional area 26 to highest cross-sectional area highest positions ranging from about 4: 1 to about 9: 1.

The generally circular shaft 28-, which tapers from a base q with a diameter of from about 0.76 mm to about 1.27 microns, as noted above, to a peak diameter of from about 0.41 mm to about 0.51 mm, is proved to be suitable for the embodiment discussed here. In particular, it generally provides a circular cross-sectional diameter of about 0.46 mm at the point of highest position

area about 0.17 mm. A generally circular cross-section of the base 26 with a diameter of about 1.0 mm provides a cross-sectional area of ​​the base of about 0.81 mm⁸. This construction results in a ratio of the cross-sectional area of ​​the base to the cross-sectional area at the highest point of about 5, which is within the above range.

The catch means 10 is connected to the shaft 28 and preferably abuts the distal end of the shaft 28. The catch means 30 project radially outwards and outwards from the circumference of the shaft 28 and may further have a vector component which extends longitudinally, i.e. is dimensioned to the substrate 24 or from him. As used herein, the term catch means any protrusion to the side relative to the circumference of the shaft 28 (other than small irregularities on the circumference of the shaft 28) which resists separation or sensing from the receiving surface. The term circumferential means means the outer surface of the protrusion 22. The term radial means from the perpendicular to the substrate 24 or to it, wherein! this perpendicular passes through the origin 16, which is usually centered at the base of the base 26.

Specifically, the lateral protrusion has the vector component rov

It should be noted that the gripping means 25 and the shaft 28 may have. both lateral and longitudinal vector components. It is important that the sharply defined end of the distal end of the shaft 28 is visible, or that the boundary between the shaft 28 and the catch means 25 is not recognizable at all. It is only necessary that the longitudinally oriented face of the circumference of the shaft 28 be interrupted, so that the catching means 25 has a face with the vector component parallel to the plane of the substrate 24 and facing it.

Capture means 25^m&amp; that have a larger lateral runout JS than the shaft 26 or vice versa, as required. As shown in the figures, the catch means 290^es preferably generally arcuate and may have a regressive curve. If the catch means 25 has a curved curve, the catch means 25 comprises a segment which longitudinally approaches the substrate at the base or at a position laterally spaced from the base 26. This segment is laterally oriented towards the shank 28, although the segment may not necessarily be oriented to the origin. 26.

The gripping means 25 of each protrusion in the array of protrusions 22 comprising the fastening system 20 may be oriented to the side in substantially the same direction if the relatively one-way predominant properties of the fastening system, such as peel strength and shear strength, are desired, or may be random. oriented to securing in essence; isotropic properties in lateral directions. Capture means 25^mIt may be formed by hook-like spikes which extend substantially from one side of the shaft 28 to define a substantially convex contour and penetrate the opening of the receiving surface to capture the strands or fibers of the receiving surface at the inner radius of curvature of the catch means 25. 30 and the strands of fibers of the receiving surface prevent the fastening system 20 from being released from the receiving surface until the peel and shear strengths of the fastening system are exceeded. The catch means 25b, y should not protrude radially too far towards the sides, otherwise the catch means 30 may not penetrate the opening in the receiving surface.

The cross-sectional area and geometry of the gripping means 10 are not critical as long as the gripping means 10 has a structural integrity that provides sufficient shear and flexural strengths to cover the required peel strengths. and in shear at a fastening system 20 having an array of protrusions 22 of a given density. For the embodiment described herein, a hook-shaped gripping means 32 having a maximum lateral extension JS ° d of the center center to the remote side circumference of from about 0.79 mm to about 1.4 mm is suitable. If an array of protrusions 22 is selected for the fastening system 20, the protrusions 22 can be arranged in any combination and density according to the requirements for achieving peel and shear strengths, required for the special application of the fastening system 20- In general, as the field density increases, the resistance to peeling and shear increases in a linear manner. The individual protrusions 22 should not be so tightly spaced as to interfere with the gripping means JQ of adjacent protrusions 22 and prevent them from being caught by the strands and fibers of the receiving surface. Conversely, the protrusions 22 should not be spaced too far apart so that to require an excessive area of ​​the substrate 24 to provide the fastening system 20 with adequate shear and peel strength.

It is advantageous to arrange the array of protrusions 22 in rows so that each protrusion 22 generally has the same distance from the adjacent protrusion 22. As a rule, the rows are oriented in the machine direction and the cross-machine direction according to the manufacturing process described and defined below. across the machine to provide a generally uniform stress field in the fastening system 20 and the receiving surface when separation forces are applied to the fastening system 20 ·^:/Λί·;_0Δ·ΐΔ·ΧΊ?rika,'·....·.'-0.00 0 ·

- 19 and receiving area.

The term "pitch" as used herein means the distance, measured either in the direction of the swarms or across the machine, between the centers of the bases of the bases 26 of the protrusions 22 in adjacent rows. Typically, a fastening system 20 having an array of protrusions 22 with a pitch of from about 1.02 mm to about 5.08 mm in both directions is suitable, with a pitch of about 2.03 mm being considered most preferred. Adjacent rows in the cross-machine direction are preferably offset by approximately half the pitch in the transverse machine direction to double the distance in the machine direction between adjacent rows across the machine.

The protrusions 22 may be considered arranged in a matrix on a one square centimeter grid having an array of protrusions 22 having about 2 to about 10 rows of protrusions 22 per centimeter in both the machine direction and the cross-machine direction, preferably about 5 rows of protrusions 22 per centimeter in every direction. This grid will result in a fastening system 20 having about 4 to 100 protrusions 22 per square centimeter of substrate 24.

The protrusions 22 of the fastening system 50 may be formed of a heat sensitive material that is stable and maintains its shape due to its strength, but is not so brittle as to fail when the fastening system is subjected to separating forces. The term heat-sensitive here means a property of a material which gradually changes from a solid state to a liquid state as heat is generated. A failure is considered to be a situation where the extract 22 has broken or can no longer withstand the reaction in the presence of separating forces. Preferably, the material has a tensile elasticity modulus according to ASTM D-638 of from about 24 MPa to about 31 MPa.

Furthermore, the protrusion material should have a sufficiently low melting point to ensure ease of processing and a relatively high viscosity to ensure a sticky and firm consistency at temperatures close to the melting point of the material so that the stems 28 can be stretched and the engaging means βθ can be easily shaped according to the manufacturing method described below. . It is also important that the protrusions 22 be viscoelastic to allow

- 20 large variations in the parameters affecting the structure of the protrusion 22, and in particular the geometry of the catch means. A material having a complex viscosity of from about 20 to about 100 Pascal seconds at a substrate application temperature of 24 is suitable.

Viscosity can be measured with a Rheometrics Model £ 00 mechanical spectrometer using dynamic operating mode at a sampling frequency of 10 Hz and 10 0/0 material stress. A disk-like or plate-like geometry is preferred, especially with a disk having a radius of about 12.5 mm and a gap of about 1.0 mm between the disk and the plate.

The protrusions 22 are preferably formed of a thermoplastic material. The term "thermoplastic" refers to the non-crosslinked poles of a thermally sensitive material that flows under the application of heat or pressure. Hot melt adhesive thermoplastics are particularly well suited for the production of a fastening system. 20 according to the invention, in particular according to the procedure described and defined below. The term adhesive and hot-melt means a viscoelastic thermoplastic which retains its residual stress when solidified from a liquid state. Hot-melt polyester and polyamide adhesive thermoplastics are particularly suitable. The term polyesters ** and polyamides * as used herein means chains having repeating ester and amide units.

If a hot melt polyester adhesive material is selected, it is found that an adhesive having a complex viscosity of about 23-2 Pascass seconds at a temperature of about 194 ° C works well. When a hot melt polyamide adhesive is selected, it has proven to be a well-functioning adhesive having a complex viscosity of about 90-10 Pascal seconds at about 204 ° C. A hot melt polyamide adhesive, available from Henkel Company of Kankakee, Illinois, under the trademark Macromelt 6300, was found to work well.

The protrusions 22 described above can be manufactured⁷ in a manner involving depositing discrete amounts of heated, heat-sensitive material on a substrate 24 that is transported relative to the selected storage means

heated heat-sensitive material. More specifically, the process comprises the steps of forming a heat-sensitive material as described above and heating it to at least a melting point so that the heated heat-sensitive material is in a fluid fluid state.

The substrate 24 is fed and transported relative to the means for storing this heated material. A means is used to store discrete amounts of heated, heat sensitive material. Discontinuous amounts of heated, heat-sensitive material are deposited on the substrate from the deposition means. One skilled in the art will appreciate that the deposition means for storing a discontinuous amount of heat sensitive material may be conveyed and the substrate 24 may be held stationary or, preferably, the substrate is conveyed and the deposition means kept held, to provide relative transport between the substrate 24 and the viewing means. .

During the transport of the substrate 24 and the deposition of discontinuous amounts of heat-sensitive material which form the protrusion 22, two directions are defined. The first direction is the direction of transport of the substrate with respect to the means for depositing heat-sensitive material. The second direction is the direction of depositing such material on the conveyed substrate 24 at the time of depositing. The tight angle β is defined between the first direction of transport and the second direction of storage.

To provide the desired shear strength properties defined below, the tight angle θ is preferably obtuse. In general, the obtuse angle β is closer to around 100 °, either from larger or smaller angles, which it typically has; resulting in a fastening system 20 having relatively greater shear strength. It should be appreciated that the preferred angle of about 100 ° may vary somewhat with the means 76 selected to deposit the heated heat sensitive material on the substrate 24.

During the process of depositing the heated, heat-sensitive material on the substrate 24, a rate difference preferably occurs between the conveyed substrate 24 and the deposited heat-sensitive material. Such a velocity difference is considered positive if the velocity of the substrate, in the first direction, is greater than the velocity of any means, such as cells J6 in the platen used to deposit hot heat sensitive material at the point of depositing such material on the substrate 24. the speed difference is considered to be negative if the speed of the transported substrate 24 is lower, It will be apparent to those skilled in the art that if the means for depositing the heated heat-sensitive material at the point of depositing such material on the substrate 24 is held still. ⁰ the substrate 2 £ is transported, there is always a positive speed difference. By creating a positive velocity difference, the viscoelastic theological properties of the heat-sensitive material can allow the material to stretch to the side and the desired fastening properties, especially the desired resultant shear strength properties.

Referring further to Figure 2, the fastening system 20 of the present invention can be fabricated using a modified gravure printing process. Gravure printing is well known in the art, as evidenced by U.S. Patent No. 4,643,130, which is incorporated herein by reference.

As shown in Figure 2, the substrate 24 can be moved. through the slit JO formed between the opposing rollers, the black roller J2 and the support roller J4. The rollers J2 and 74 have substantially parallel center lines arranged substantially parallel to the plane of the substrate 24. Each of the rollers J2 and 74 rotates about its respective axis, so that the rollers 72 and 74 have substantially the same area and direction in the slot 70 *.

If necessary, the rollers 72 and J4 may also have substantially identical circumferential speeds at the point JQ.

If desired, both the printing roller 72 and the support roller J4 may be driven by an external driving force (not shown) or one roller may be driven by an external driving force and the second roller may be driven by frictional engagement with the first roller. An AC electric motor with an output of 1,500 watts has been shown to provide adequate driving power. By rotating the rollers 72 and J4 they activate the depositing means

The rollers J2 and J4 may rotate at the same or different circumferential speeds. It is only: it is necessary for both cylinders 72 and 74 to rotate in the same direction at the clamping point 70 »

The deposition means should be able to provide the material temperature of the protrusions 22 in the liquid state, provide a substantially uniform spacing between the protrusions 22 both in the machine direction and across the machine, and provide the desired density of the protrusions 22 within the field. The deposition means should also be able to form protrusions having different base diameters and stem heights 28. Specifically, the printing roller 72 forms a depositing means for depositing the protrusions 22 on the substrate 24 in the desired field described above, or another combination, according to the manufacturing method of the invention.

The term depositing means refers to a device that conveys the liquid material of the protrusion from the free volume to the substrate 24 in dosages corresponding to the individual protrusions 22. The term storage means transporting the material · of the protrusions from bulk 22.

One suitable depositing means for depositing the protrusion material on the substrate 24 is an array of one or more cells 76 in the printing cylinder 72. The term cell as used herein means any cavity or other component of the printing cylinder 12 that transfers the protrusion material from the source to the substrate 24; deposits this material on the substrate 24 in discontinuous units.

The cross-sectional area of ​​the cell 76 considered at the surface of the printing cylinder J2 generally corresponds to the base of the base of the protrusion 22. The cross-section of the cell 76 should be approximately equal to the desired cross-section of the base 26. from base 26 to the highest position point or segment. However, while the depth of cell 76 increases to more than about 70 percent the diameter of cell 76, longitudinal

- 24 the dimension of the protrusion 22 remains substantially constant. This is because not all of the liquid material of the protrusion is withdrawn from the cell 76 and deposited on the substrate 24. Due to the surface tension and viscosity of the liquid material of the protrusion, a portion of it will remain in the cell 76 and will not be transferred to the substrate 24.

A blind, generally cylindrically shaped cell having a depth between about 50 and about 70 percent in diameter is appropriate for the embodiment described herein. If desired, the cell may be slightly inclined into a truncated cone shape to accommodate conventional manufacturing processes such as chemical etching.

In the case of truncated cone shaping, the clamped bevel angle of the cell 76 should not be greater than about 45 to obtain the preferred bevel of the shaft 2c and to provide the base to highest position ratios listed above. If the bevel of the cell 76 has a larger closed angle, this may result in the protrusion 22 having too large a bevel. If the clamped angle is too small or the cell 76 is cylindrical, this may result in a shaft. 2S of generally uniform cross-section and thus higher stress areas. For the embodiment described herein, a suitable protrusion 22 provides a cell J6 having a closed angle of about 45 °, a cylinder circumference diameter of about 0.89 mm to about 1.22 mm, and a depth in the range of about 0.25 mm to about 0.51 mm.

J2 printing roller. and support roller J4 úy^mwere to be compressed in the plane connecting the axes of the rollers to extrude the adhesive from the cells: 76 in the printing roller 72 onto the substrate 24 and to provide a sufficient frictional load. for driving the opposing cylinder if it is not externally driven. The backing roll should be somewhat softer and more pliable than the take-up roll 72 to provide a flexible backing of the protrusion material when deposited on the backing 24 of the take-up roll 72. A support roller J4 having a rubber coating with a Shore A hardness of from about 40 to about 60 is suitable.

The temperature of the platen 72 is not critical, but the platen 72 should be heated to prevent the protrusions 22 from solidifying during transfer from the source by depositing on the substrate 24;

- 25 ~

In general, a temperature close to the material source temperature is required. It has been found that the temperature of the printing cylinder 72 around 197 ° C works well.

It should be noted that a cooling cylinder may be required if the substrate 24 is adversely affected by the heat transferred from the protrusion material. If a smoothing roller is desired, it can be incorporated into the backing roller 74 using means well known in the art. This arrangement is often necessary when using polypropylene, ethylene polymers or other polyolefin substrates 24.

The material used to form the individual protrusions 22 must be maintained in a source that provides the required temperature for applying the protrusions 22 to the substrate 24. Typically, a temperature slightly above the melting point of the material is required. The material is considered to be at or above the melting point if the material is partially or completely in a liquid state.

If the source of protrusion material is maintained at too high a temperature, the protrusion material may not be sufficiently viscous and may lead to the formation of gripping means 30 which engage laterally with the protrusions 22 adjacent in the machine direction. If the temperature of the material is very high, the protrusion 22 will flow into a small, somewhat hemispherically shaped drop, and the trapping means 30 will not form. Conversely, if the source temperature is too low, the protrusion material; is not transferred from source to. material storage means or subsequently may not be properly transferred from the storage means 76 to the substrate 24 in the desired field or combination. The material source should also provide a generally uniform temperature profile of the material, be in communication with the means for depositing the adhesive material on the substrate 24, and be easily replenished when the protrusion material is emptied.

A suitable source is trough 80, which is substantially co-expandable with that portion of the dimension across the printing cylinder 72 of the machine which has cells 76 and adjacent thereto. The trough 80 has a bottom with a closed end, an outer side and an end. The top can be open or closed. The inside of the trough 80 is open,

·. '/':. · '7'. .-. . '. '· '77 .7--7'7; -7 / .7: 7,7: 718) 7777λ77: ζ7 - '^; 7777.77 / 78ηζί7; 6) ;; ΑΛ7Λϊν7Λύ ^ · ύ ^: ι · ί7ην &lt;.&gt; / ·· 7; 87 ?.

Allowing the liquid material present in the trough 80 to freely touch and communicate with the circumference of the printing cylinder 72 and to enter the cells 76 or to communicate with any other desired means for depositing heat-sensitive material on the substrate 24;

The source is externally heated by known means (not shown) to keep the protrusion material in a liquid state and at a suitable temperature. The preferred temperature is above the melting point but below the value at which a significant loss of viscoelasticity occurs. If desired, the liquid material within the trough 80 can be mixed or recirculated to promote homogeneity and even temperature distribution.

Opposite the bottom of the trough 80 is a wiper 82 which controls the amount of protrusion material fed to the platen 72, the wiper 82 and trough 80 are kept stationary as the platen 72 rotates, allowing the wiper 82 to wipe the circumference of the cylinder 22 and scrape any protrusion material. which is not stored in the individual cells 76, from the cylinder 72, and allows such material to be recycled. This arrangement allows the protrusion material to be deposited from the cells 76 on the substrate 24 in a desired field according to the geometry of the cells 76 on the circumference of the printing cylinder 72. As seen in Figure 2, the wiper 82 preferably lies in a horizontal plane, After lying on the substrate 24, the protrusions 22 can be cut off from the printing cylinder 12 and the depositing means J6. If desired, the trimming can be completed as a separate process in the method for trimming the protrusions 22 to the fastening system catch means and waste. The term "waste" as used herein means any material cut from the protrusion 22 that does not form part of the fastening system 20. Depending on the adjustment of various parameters, such as the angle between the substrate 24 and the depositing means 76, the speed difference, the viscosity of the heated, heat sensitive material, cell J6, a separate trimming step may not be necessary. Pruning can occur naturally as

- 27 substrate functions. 24 »transported away from the point. storage, if used, the trimming means 78 should be adjustable to provide different sizes of protrusions 22 and lateral, runout of the gripping means 8 and also to ensure parallelism in the field in the transverse direction of the machine. "Cutting device **" means any device or component which separates the waste from the fastening system 20 in the longitudinal direction. The term "trimming" refers to the process of separating the waste from the fastening system 20, as described above. The trimmer 78 should also be clean and should not corrode, oxidize, or transfer corrosive substances and contaminants (such as waste material) to the protrusions 22. A suitable cutting means is a wire 78 positioned generally parallel to the centerline of the rollers 72 and 74 and spaced from the backing 24, which is somewhat greater than the perpendicular distance from the highest position of the solidified protrusion 22 to the backing 24.

Preferably, the wire 78 is electrically heated to prevent the formation of molten protrusion material 22 on the trimming means 78, to cover any cooling of the protrusions 22 that occurs between the time the protrusion material leaves the heated source and the time the trimming 1c occurs, and to promote stretching the catch means to the sides. Heating the trimmer. J8 should also ensure an even temperature distribution across the machine so that a field of protrusions is created. 22 having a substantially uniform geometry.

In general, as the temperature of the protrusion material increases, the relatively colder temperature of the cutting means wire 78 may be used. As the speed of the substrate 2j decreases, the hot wire 78 cools less frequently as each protrusion 22 and debris are cut, allowing for greater feasibility of using the hot wire 78 at the same lower power temperatures. It should be noted that as the temperature of the hot wire 78 increases, this will result in a protrusion 22 having a relatively shorter shaft 28. Reverse length

·Ί · \\

28 to the shank 28 and the lateral length of the catch means 30 will increase in reverse as the temperature of the hot wire 78 decreases.

The JS actually touched the protrusion 22 so that trimming could occur. The protrusion 22 can be cut by radiant heat emitted by the cutting means J8. For the embodiments described herein, it has been found to be a suitable chrome-nickel wire JS having a diameter of about 0.51 mm heated to a temperature of from about 343 ° C to about 416 ° C. It will be appreciated that a knife, laser cutting or other cutting means 78 may replace the hot wire J8 described above.

It is important that the trimming means 78 be placed in a position that allows the protrusion material to be stretched before the protrusion is cut from the waste. If the JS trimmer is placed too far from the ground plane? 24 »the protrusion material will pass under the trimming means JS and will not be caught by it, thus creating a very thin gripping means JO which will not be placed at a proper distance from the substrate 24 or adjacent protrusions 22. Conversely, if the trimming means 78 is placed too close to the plane background 24. » J8 clipping tool:

shorten the shaft 28. and the catch means JO are not formed;

Hot wire cutting means JS, placed approximately 14 mm to 22 mm, preferably about 1 mm in the machine direction and from the clamping point JQ, approximately 4.8 mm to 7.9 mm radially outwards from the support roller J4 and approximately 1 mm. .5mm to about 4.5 .mu.m radially outward from the printing cylinder 72; adequately stored for the method of manufacture described herein

During operation, the substrate 24 is conveyed in the first direction relative to the depositing means 76. More specifically, the substrate 24 is conveyed through the gap JO and is preferably towed by a draw roller (not shown).

The area of ​​the substrate 24 for continuously depositing the protrusions 22 and 1 removes portions of the substrate 24 having the protrusions 22 disposed thereon. A direction generally parallel to the main direction of transport of the substrate 24 when. passes through the gap JO, it is referred to as the machine direction '' - Machine direction as indicated by the arrow Jj&gt; on

<img file="CS9101995A3_D0002.tif" />

Fig. 29 is generally perpendicular to the axis of the printing cylinder 72 and the support cylinder 24. The direction generally perpendicular to the machine direction and parallel to the plane of the substrate 2 is referred to as the transverse direction of the machine. "Clamping plane" is a plane containing a straight line and tangent to the printing cylinder J2 and the support! cylinders 76.

After storing the protrusion material. 22 from cell 76 to the base of cylinder J2^and 74 continue to rotate in the directions indicated by arrows J5 in FIG. 2. This results in a period of relative displacement between the conveyed substrate 24 and the cells 76 during which (prior to trimming) the protrusion material bridges the substrate and the platen 72. The relative displacement continues, the protrusion material stretches until it is cut, and the protrusion 22 is separated from the printing cylinder cell 76. 20.

As noted above, it may also be necessary to trim the individual protrusions 22 from the printing cylinder 72 as part of the process by which the gripping means is formed. remains with the fastening system 20 and waste (not shown) which remains with the printing roller 72 and can be recycled as needed. After the protrusions 22 are cut from the waste, the fastening system 20 is allowed to solidify before the protrusions 22 come into contact with other objects. After the protrusions 22 have solidified, the substrate 24 can be wound into a roll for storage as needed.

The substrate 28 can be conveyed through the slit 70 in the first direction at about 3 to 31 meters per minute. The substrate 26 can be drawn through the slot JO at a speed of from about 50% to about 15% less than the circumferential speed of said printing roller J2, thereby obtaining a percentage positive speed difference up to a 15 percent negative speed difference. Preferably, a positive speed difference of at least 2 o / o is used. If a device is used

- 30 of Fig. 2_r the speed of the conveyed substrate 24 is therefore at least about 2% higher than the surface speed of the printing roller 72.

The fastening properties, in particular the shear strength of the fastening system 2CT or the individual protrusion 22, can also be influenced by the tight angle formed between the two directions occurring in the dynamic processes of this process, the first direction being the main transport direction of the substrate 24 and the second direction being the direction in which heated heat sensitive material applied to the conveyed substrate 24. It will be apparent to those skilled in the art that if this device is used to deposit heated heat sensitive material on the substrate 24 at the time of deposition, the angle Z will be approximately 90 °, since the first direction of transport of the substrate 24 through the slit 70 is generally perpendicular to the second direction. by which the heated, heat-sensitive material is withdrawn from the cell 76 in the circumference of the printing cylinder 72.

As noted above, the substrate 24 may be drawn from the nip plane of the printing cylinder 72 at a particular angle 9S which is sharp with respect to the clamping plane 70 and blunt with respect to the direction of deposition of the heated heat sensitive material on the conveyed substrate 24. Typically; as the tightening angle decreases between the transport direction of the substrate after passing through the slot 70 and the clamping plane (or more generally the angle θ) between the first transported substrate direction 24 and the second heated heat sensitive material deposition direction / on the transported substrate 24, the resulting fastening system 20 will have relatively high strength. in shear, as shown in more detail in the figures below: and as described in more detail below.

This relationship generally applies, regardless of the relative speed difference between the transported substrate 24 ^and by means of depositing heated, heat-sensitive material on the conveyed substrate 24. This relationship also applies to both positive speed differences and negative speed differences. The process by which the conveyed substrate 24 is drawn at an obtuse angle p&gt; with respect to the depositing direction

of heated heat sensitive material to a conveyed substrate of about 100 ° to about 110 °, and more particularly where the conveyed substrate 24 is pulled from the plane of the clamping plane JQ at a tight angle jr of about 5 to about 40 °, is found to function well.

In Fig. 3, it is generally seen that as the positive speed difference increases, the constricted angles 22 relative to the substrate 24 decreases and the protrusions 22 become more side-oriented and closer to a direction parallel to the direction of the substrate 24. This relationship holds and is substantially linear for two selected clamping angles of 15 ° and 35 ° between the clamping plane 70 and the direction in which the substrate 24 is pulled away from the clamping 70, and includes a range from a negative 11 percent speed difference to a positive 16 percent positive speed difference. .

As can be seen in Figure 4, the shear strength of the mechanical fastening system is measured in the gram force of a sample of the fastening system 20 having an area of ​​about 4.84 cm. This sample size was chosen because it is large enough and is typical of the sizes used in the above application. Shear strength is tested using model material No. 16-10 supplied by Guilforď Loop Corporation as the receiving surface. The shear force can be measured by pulling the secured fastening system 20 and the receiving surface in opposite directions, these directions being generally parallel to the planes of the corresponding substrate 24 and the plane of the receiving surface. During the measurement, the tight angle of the protrusions 22 is generally oriented in the same direction as in which the substrate 24 is pulled by the drawing machine (the protrusion 22 of FIG. 1 is pulled to the right). The method used to determine the resistance of the fastening system 20 to shear forces is set forth in more detail in U.S. Patent No. 4,699,622, which is incorporated herein by reference to describe a suitable technique for measuring shear forces.

Referring to Fig. 4, it can be seen that the shear force of the fastening system 20 is related to the clamped diagonals 28 of the protrusions 22 and thus to the speed difference, based on

- 32 of the relationship indicated in Fig. 3- As. shown in Fig. 4, it is preferred that the angle between the shanks 28 and the substrate 28 be less than about 70 °, and preferably less than about 65 °, to maintain a shear strength of at least about 1000 g at 4&gt; 8 cm, because it can be seen that the shear strength decreases rapidly, the more the stems 28 become perpendicular to the substrate than about 65 to 70 °. Also from FIG. 4 it can be seen that for all recorded values ​​of clamped shank angles, greater shear strengths are obtained if the substrate 26 is pulled away from the clamping plane 72 at an angle θ of 1515 ° than at an angle greater than 35 ».

It can be seen from Fig. 4 that it is generally required that the angle Λ. between the shaft 28 of the protrusion 22 and the substrate 24 was less than 70 °. In particular, an angle Λ- of from about 20 ° to about 65 ° is desirable. This relationship again applies to both clamping angles Τ 'between the clamp. the plane of the slit 72^and the plane in the direction in which the substrate 24 is withdrawn after leaving the slit 72 *

Giant. 5 illustrates the relationship between the speed difference of the conveyed substrate 24 and the shear strength of the mechanical fastening system 20 achieved by such a speed difference. Both positive and negative speed differences are shown in this figure. Giant. 5, however, generally shows that a positive speed difference of about 2 to 18 percent is desired. This relationship again applies both to the described clamping angles T ~ between the clamping plane of the slot 70 and. the plane in the direction in which the substrate transported after leaving the slit 72 *

Another factor that may be considered by those skilled in the art is the radius of curvature of the platen 72 and its relationship to the velocity difference and angle θ between the substrate 26 and the nip plane 70. As the radius of curvature of the platen J2 decreases, the debris 38 22, which is formed, are pulled away from the substrate 24 at an angle which, in the vicinity of the slit 22 3^evand^what perpendicular to the clamping plane of the slot 72, the solidification will typically have a relatively larger angle than the protrusion 22 made in conditions that are similar, except for the use of a larger radius of curvature.

33 of the printing cylinder 72

To eliminate the occurrence of a decrease in shear force, based on the relationship of FIG. 4, the velocity difference or angle Z? If the radius of curvature of the press^rIf the speed difference or the gripping angle 7 increases or decreases without adequate compensation, the angle (X) of the protrusion 22 and thus the shear strength of the fastening system 20 may not have the shear strength required for use. In particular, if the speed difference and the clamping angle do not correspond to the radius of curvature of the printing cylinder 72, the waste of the protrusion 22 may be oriented too perpendicular to the substrate 24 and upon solidification, the clamping angle © c of the protrusion 22 may be greater than required. with less shear strength than required.

To provide an improved fastening system 20 according to the invention, it is important to use a device for making the fastening system 20 imparting a vector orientation that is not orthogonal (more than about 10 ° off-axis in any direction) to the plane of the substrate 24 in the base 26 of the protrusion 22 the amount of heat-sensitive material deposited. If the device of FIG. 2, the two means for imparting a non-orthogonal vector orientation to the substrate 24 of the discontinuously deposited heat-sensitive material include the above-mentioned velocity difference and the acute angle θ between the nip plane of the slot 70 and the conveyed substrate 24.

Various deviations of the described apparatus and method within the scope of the invention are feasible. If a relatively thick substrate 24 and sufficient tension are used if necessary, the backing roll 74 of the apparatus of FIG. 2 may be omitted. forms an S-shaped arc around the printing cylinder 72. There is no nip in this arrangement

34 as shown in FIG. 2, but instead allows the substrate 24 to deposit heated heat-sensitive material from the cells 76 of the printing cylinder 72. depositing the heated heat-sensitive material on the substrate 24, the substrate must have sufficient tensile strength to prevent tearing and to maintain the stress required to properly deposit the heated material. heat sensitive.

The following are four illustrative, non-limiting examples showing how various manufacturing process parameters can be combined, varied, kept constant, and used to make reattachable fastening systems 20 having the desired structure, geometry, and tensile strength. A representative protrusion 22 for the fastening system 20 of each example is shown in Figures 6A-9B.

Considering — first, the parameters kept constant in all four examples, each of the following examples using the above adhesive: hot-melt polyester-based 7199 Bostik. The adhesive is maintained at 179-181 ° C and is applied to a 0.13 to 0.1 Emm thick kraft bleached paper substrate 24 conveyed at a constant speed of about 6.31 meters per minute.

The device selected for storing the heated heat-sensitive material is similar to that shown in Fig. 2 and has approximately a printing cylinder 72 with a diameter of 16 cm and a support cylinder 74 with a projection of approximately 15.2 cm. The printing cylinder 12 has an array of truncated cone-shaped blind domes 76, each about 1.0 nm in diameter, on the circumference of the printing cylinder 72, about 0.46 mm deep, and housed in a matrix of about 75 cells per square centimeter.

Each example uses a cutting means 78, in particular a hot wire 7§ with a diameter of 0.76 mm and a depth of about 61 .mu.m. The hot wire 7S is laid horizontally about 5.1 mm from the printing cylinder 72 and about 22.9 mm from the support cylinder 74 Ρ^Γθevery example. The hot JS wire is electrically heated.

Λ / ϊ .; ΰ i.ť / ·· Ů) · 11 V '.-'. '. V · ·; Ji '· -Λ .'-.'. · '* I r- · Λ. ; i&gt;. - S t.i; λ AΈ

Considering the parameters varied in the examples below, the electrical energy supplied to the hot wire 78 is adjusted according to the distance from the hot wire JS to the substrate 24 and the speed of the printing roller 72. to account for cooling_rwhich occurs between the circumference of the hot wire; 78 and the surfaces of the protrusions 22 formed according to various examples. The angle θ between the depositing means 76 and the substrate 24 is varied to show the effect of two different angles β. Specifically, the examples use angles of 15 ° and 35 ° between the conveyed substrate 24 and the nip plane 70. Also, the speed difference between the storage means 76 and the conveyed substrate 24 has been varied and includes both positive and negative speed differences. For each example, either the speed difference was kept constant and the angle f was set or vice versa, so that both parameters are not set in the same example.

EXAMPLE I

Referring to Figs. 6A and 6B, the protrusion 22 of Fig. 6A is fabricated according to the parameters of Table IA and the protrusion 22 of Fig. 6B is fabricated according to the parameters of Table ΓΒ. Both protrusions were made with a positive 20/0 speed difference, but differ in the clamping angle between the clamping plane of the slot 70 and the conveyed substrate 24 from an acute angle of 15 ° to an acute angle; 35 °. Otherwise, the parameters used in the protrusion manufacturing method of Figs. 6A and 6H are the same.

From the bottom of Tables IA and IB, it can be seen that, in accordance with the figures in Figures 4 and 5, the protrusion 22 having a 15 ° angle / shear strength provides almost 35% greater than the strength of the protrusion 22 of Figure 1. 6B having an angle T ~ 35 °. However, the protrusion 22 of Fig. 6B is almost 25/0 slimmer and has less lateral projection.

<td>Operating parameters</td><td>Tab. IA</td><td>Tab.IB</td>

<td>speed difference</td><td> + 2 0/0</td><td> + 2 0/0</td>

<td>The angle between the plane of the substrate and the clamping plane</td><td> 15°</td><td> 35°</td>

<td>Hot wire energy / W /</td><td> 95,2</td><td> 95,2</td>

<td>Properties of protrusions</td><td>Tab.IA</td><td>Tab.IB</td>

<td>p Shear strength / g / 4.8 cm /</td><td> 6,600</td><td> 5,100</td>

<td>Clamping angle · cL ·</td><td> 66°</td><td> 60°</td>

<td>Maximum lateral run-out</td><td> 2,14</td><td> 1,45</td>

<td>/ 0.025 cm /</td><td></td><td></td>

<td>Height / 0.025 cm /</td><td> 2,23</td><td> 2,78</td>

<td>Capture means diameter</td><td> 6</td><td> 7</td>

<td>/ 0.0025 cm /</td><td></td><td></td>

<td>EXAMPLE H</td><td></td><td></td>

Giant. 7A and 7B show protrusions made according to the parameters of Tables IIA and IIB and are directed to protrusions having a speed difference of 6.6 o / o but a very small angle subtended by the clamping plane of slot 70 and the direction of the conveyed substrate from about 15 ° to about 35 °. The gripping means 22 of the protrusion 22 of Fig. 7B has a pronounced orientation back towards the origin J6 of the base 26. However, in accordance with Figs. Fig. 7B. One explanation for the increased shear strength of the protrusions 22 of Fig. 7 is that the reverse orientation of the gripping means 30 prevents a substantial amount of receiving surface fibers from being caught by the fastening system 20, and such uncaptured fibers do not provide sufficient resistance to shear forces.

Operating parameters Tab.IIA

Speed ​​difference +6.6 o / o

Angle r- between the substrate 15 ° and the clamping plane

Hot wire energy / W / 80.0

Properties of protrusions p

Shear strength / g / 4.8 cm / 5,900

Clamped angle 55 °

Maximum lateral runout 1.94 / 0.025 cm /

Tab.IIB +6.6 o / o 35 °

95,2

5,500

58°

2,28

- 37 Tab.IIA Tab.HB

Height / 0.025 cm / 2.24 2.45

Capture diameter 6 5 / 0.0025 cm /

EXAMPLE ΙΠ

In Example III, the speed difference between two protrusions 22, each having the same angle 7 * between the clamping plane and the plane of the conveyed substrate 24, is varied. The constant angle for both protrusions 22 of Figs. 8A and 8B is approximately 35 °. The protrusion 22 of Fig. 8A has a positive speed difference of about 16 o / o, while the protrusion of Fig. 8B is a protrusion 22 having a positive 2 o / o speed difference. It will be apparent to those skilled in the art that the catch means 50 of the protrusion 22 of FIG. 8A has a very large maximum lateral projection 8 8, almost 71 o / o larger than from FIG. 8B. The protrusion 22 of Fig. 8A has such a large lateral projection 3S that the protrusion 22 can slide to the side parallel to the plane of the substrate 24 when it is caught in the receiving surface, provided, of course, that I slide such! corresponds to the orientation of the protrusion profile 22 »

The protrusion of Fig. 8A also has a shear strength almost 1G o / o greater than the protrusion of Fig. 8B. This result corresponds to the graphs in Figs. 3, 4 and 5. · As the speed difference increases, the grip angle A- decreases according to Fig. 3 and thus the shear strength according to Fig. 4 increases. shear strength according to Fig. 5 »

<td>Operating parameters</td><td>Tab.IHA</td><td>Tab.IIIB</td>

<td>Speed ​​difference.</td><td>+16 o / o</td><td>+2 o / o</td>

<td>Angle 7 between the substrate and</td><td> 35°</td><td> 35°</td>

<td>clamping plane Hot wire energy / W /</td><td> 128</td><td> 95,2</td>

Properties of protrusions

Shear strength (g) 4.8 cm 2 / 5,600 5,100

- 38 Tab.HIB

60° ,45

2.7ε

<td>Clamping angle Λ.</td><td>Tab.IIlA 45 °</td>

<td>Maximum lateral run-out</td><td> 4,15</td>

<td>/ 0.025 cm /</td><td></td>

<td>Height / 0.025 cm /</td><td> 1 ,97</td>

<td>Capture means diameter</td><td> 3</td>

<td>/ 0.0025 cm /</td><td></td>

A comparison of the results of Examples 1 and III shows that both the highest and lowest shear strength values ​​occur in the protrusions 22 of Example I having a positive 2 o / o velocity difference. This difference in shear strength means that at lower positive speed differences, the manufacturing process is more sensitive to changes in angle / pinch between the substrate 24 and the nip plane 70.

EXAMPLE IV

The protrusions 22 shown in Figs. 9A and 9B, made according to the parameters of these figures, each have a negative speed difference of 11 o / o and exhibit substantially reduced shear strengths compared to the protrusions 22 of the previous examples. However, in accordance with Figs. 4 and 5, the protrusion 22 of Fig. 9A, having an angle V? giant.

9B having an angle θ 'formed between the conveyed substrate 24 and the clamping plane of the slot 70 of 35 °.

Operating parameters

Speed ​​difference Angle Between substrate and clamping plane Hot wire energy / W /

Tab.IVA

-11 0/0 15°

Tab.IVH

-11 0/0 35°

80,0

80,0

2,600

86°

Properties of protrusions

Shear strength / g / 4.8 cm / 3.300

Angle Λ- 87 °

<td></td><td>Tab.IVA</td><td>Tab.IVH</td>

<td>Maximum lateral run-out</td><td>T, -857</td><td> 2,05</td>

<td>/ 0.025 cm /</td><td></td><td></td>

<td>Height / 0.025 cm /</td><td> 2,46</td><td> 2,52</td>

<td>Capture means diameter</td><td> 6</td><td> 5</td>

<td>/ 0.0025 cm /</td><td></td><td></td>

It will be apparent to those skilled in the art that various other variations and combinations may be used. For example, several parameters may be set, including different hot wire temperatures 78, and various means for depositing heated heat-sensitive material on the conveyed substrate 24 are possible. All such combinations and variations are within the scope of the invention as defined by the following patents.