MXPA99003256A - Hook fasteners and methods of manufacture - Google Patents

Abstract

This invention is a hook fastener member (18) having rows of molded hook shaped fastener elements (114) that lie in planes aligned with the rows, with generally planar plate portions (118) at the outermost ends (117) of at least some of the fastener elements (114), the plate portions (118) lying generally parallel to the base (112) of the fastener member (18). The plate portions (118) can enhance engagement of the hook fastener members with mating loop fastener members (22), particularly with low loft non-woven loop fastener members. A method of making fastener members (18) is provided. Molten resin is extruded, and applied to a molding roller (50), creating preforms. The outermost portions of at least some of the preforms are flattened, thereby forming generally plate shaped portions. Disposable absorbent garments (10) advantageously incorporate the hook fastener members (18).

Description

S YSTEMS IN THE FORM OF GANC HO AND MANUFACTURING ETHODS BACKGROUND OF THE I NVENTIO N The invention relates to improved hook members for hook and loop fastening and methods for manufacturing hook members. In general, the hook-and-loop fasteners comprise two matching components: a hook member having straight hook-type fastener elements, and a loop member having a surface that provides fibers or fiber loops with the hooks. which the hook elements are coupled. As used herein, a "hook member" represents a member having fastener elements whose hooks extend substantially in a given plane. When in the molded form, the rods of these elements are significantly wider in the direction of their extension plane than in the thickness direction at a right angle thereto. Hook-type fasteners are generally preferred over other types of fasteners, for example, those having a mushroom type shape, since hook fasteners can provide a more secure attachment with the loops, offer advantages in manufacturing, etc.

The loop members for hook and loop fastening have been composed of knitted, woven, and nonwoven fabrics. A common example of a non-woven fabric is known by the term "spin-bonded". This is made by spinning fine filaments of plastic resin, for example, polypropylene, and distributing them in superposed layers. The fibers are bonded together in random orientations, with a diaper-like, low, thin, stretched layer of bonded and arched fibers exposed on the surface of the fabric. Since non-woven fabrics are not expensive, they are desired to be used as the loop portion of fasteners for low cost items, particularly disposable products such as diapers, surgical clothing, and sanitary napkins. It is desirable to provide useful fastener members with very low cost fabrics, non-woven fabrics of low fluffiness or other fabrics of low fluffiness.

COMPENDIUM OF THE INVENTION One aspect of the invention relates to a fastener member useful for detachable coupling with surface fibers of a non-woven, low-fluff fabric, or the like. The fastener includes a base and multiple rows of molded hook-shaped fastener elements extending from the base and exposed to mesh with the fabric. Each of the hooks forms fastener elements comprising a portion of the rod attached at one end to the base and at least a hook-shaped portion that couples the fiber attached at the opposite end of the rod portion and having a free end. . The hook-shaped fastening elements lie substantially and only in planes aligned with the respective rows. At least some of the fastener elements include a portion of fiber coupling plate in the outermost portion of the hook-shaped portion, said portion of plate lying generally parallel to the base. The plate portion provides a protruding portion in the direction perpendicular to its row that can couple the fibers on the surface of the fabric. Certain implementations of this aspect of the invention include one or more of the following aspects. The fastener member, in certain implementations, provides: a plate portion, which has a thickness, in the direction normal to the base, which is less than the height, in the direction normal to the base, of the free end of the portion Hook; the fastener elements formed of thermoplastic resin, the rod portions of the elements being integrally molded with the base, and the plate portion comprising a post-formed structure formed from the resin of the uppermost portion of the molded fastener element; substantially all the hook-shaped portions of the fastening elements in a first row extend in a direction along the row and substantially all of the hook-shaped portions of the fastening elements in the second, close row extend in the direction opposite; substantially all fastener elements include plate portions; substantially all fastener elements in the first row contain a plate portion, while substantially all the elements in the second row nearby do not; a shank portion having relatively broad substantially flat sides, a cross section of each shank portion, taken parallel to the base in the mid-height region of the shank, having a width in the direction of the row and a thickness in the direction perpendicular to the row, the width being approximately twice the thickness or more; a rod in which the width of the rod tapers from the base towards the hook-shaped portion; a central axis of the rod is inclined, in the direction of the respective row, at a substantially acute angle relative to the base. Another aspect of the invention relates to a fastening member useful for detachable coupling with surface fibers of a non-woven, low-fluff, or the like. The fastener comprises a base and multiple fibers of molded fastener elements extending from the base. Each fastener element comprises a portion of the rod attached at one end to the base, the rod being inclined, at a substantially acute angle relative to the base in the direction of the respective row of the element, and lying substantially only in planes aligned with its respective row relative to the base, and a portion of fiber coupling plate disposed at the outermost, opposite end of the rod portion, the plate portion extending transversely toward the direction of the respective row to form a protruding portion that It can attach the surface fibers of the fabric. Certain implementations of this aspect of the invention include one or more of the following characteristics. The fastener member, in certain implementations, provides a cross section of each portion of the rod, taken parallel to the base, has a width in the direction of the row and a thickness in the direction perpendicular to the row, the width being substantially greater than The spesor; substantially all fastener elements include plate portions. According to another implementation of the invention, a closure comprising a fastening member as described above and a non-woven fabric coupled thereto, the base of the fastener and the non-woven fabric being tensioned in opposite directions is provided so that Fasteners are subjected to and resist shear forces caused by the tension load, the tension acting in the thickness direction in the rod portion. Another aspect of the invention relates to a method for making fastener members comprising extruding molten resin and applying the resin to a molding roll having cavities formed around its perimeter. Pressure is applied to the resin to cause the resin to fill the cavities, thereby forming a preform of the fastening member, the preform of the fastening member comprising a base and a multitude of discrete fastener preforms integrally molded with and extending from the base to a substantially acute angle, the preforms of the fastener element aligned in at least one row comprising portions of the stem with outer ends lying on the base substantially only in planes aligned with its row. The preforms of the holding member are made in strips from the molding roll. The outermost portions of at least some of the fastener preforms are flattened, thus forming plate-like portions disposed at the outermost ends and generally parallel to the base and perpendicular to the row. Certain implementations of this aspect of the invention include one or more of the following characteristics. The method, in certain implementations, provides: flattening comprises heating the outermost ends of at least some of the fastener preforms to a temperature that is close to the melting temperature of the resin and applying pressure to the outermost ends; the heating and the application of pressure are carried out in one step; the only step comprises passing the fastener member preforms through a hot roll and compressing at least some of the fastener preforms against the hot roll; the preforms of the fastening member are formed and the outermost ends of at least some of the preforms are flattened as part of a continuous, individual procedure; the outermost ends of at least some of the fastener preforms are flattened in a post-processing operation, before flattening, differences in the heights of the fastener preforms are corrected to ensure a generally uniform height; the correction comprises compressing a slap roller against the outermost ends of the fastener preforms; substantially all fastener elements are flattened; A product is formed through this method. In another aspect of the invention, the outermost portions of some fastener elements are away from the base, thus formed, than the outermost portion of at least some of the other fastener elements. At least some of the outermost portions further away from the base are then flattened, forming generally plate-like portions disposed at the outermost ends and generally parallel to the base and perpendicular to the row. In a preferred embodiment, the forming of strips of the preforms from the molding roll causes the clamping members to extend in a direction that will be deformed to have a greater height than the clamping members in another direction. Another aspect of the invention relates to a method for improving the coupling capability of a hook-type fastener member with a loop-type fastener member or fabric. The hook-type fastening member comprising a base and a plurality of generally hook-shaped fastening elements integrally molded with and extending from the base in a given direction or in that direction and the opposite direction and lie only in planes parallel with the direction given and perpendicular to the base. The method comprises flattening the outermost ends of at least some of the fastener elements to form generally plate-like portions disposed at the distal ends and generally parallel to the base and perpendicular to the planes. The new hook-shaped fastener members "are suitable for coupling with low-fluff non-woven loop members, since the outer plate portions of the fastener elements emerging from the sides of the elements are able to slide down and Initially coupling the surface fibers of the loop member This aspect can improve the level of coupling of the fastener, especially when the fastener elements are subjected to shear stresses acting laterally with respect to the plane direction of the hook elements. With a flat top, although they provide secure attachment by the hooks, they can also avoid irritation of the skin since the contact area between the skin and the fastener elements is relatively large.This is of particular value when a fastener The hook is placed in contact with the skin of the babies. The hook can be manufactured using conventional hook member tool with simple additional post-molding steps. Other aspects of the invention relate to a disposable absorbent press having first and second opposite longitudinal end portions, and comprising an outer cover; a body side lining; an absorbent core located between the outer shell and the body's side shell; a tie member operably associated with the garment; and a fastener member operably associated with the garment for detachable engagement with the loop member, the fastening member comprising: a base; and a multitude of rows of molded hook fastener elements extending from the base. According to one aspect of the invention, the fastening elements are exposed for coupling with the loop member, each of the hook-shaped fastening elements comprising a rod portion attached at one end to the base and at least one hook coupling portion of fiber attached at the opposite end of the rod portion and having a free end, the hook-shaped fastener elements lying substantially only in the planes aligned with the respective rows. At least some of the fastener elements include a portion of fiber coupling plate in the outermost portion of the hook-shaped portion, the plate portion lying generally parallel to the base, the plate portion providing a protruding portion in the direction perpendicular to its row. Certain implementations of this aspect of the invention have one or more of the following characteristics. The plate portion has a thickness, in the direction normal to the base, that is less than the height, in the normal direction toward the base, of the free end of the hook portion. The shank portion has substantially flat and relatively wide sides, a cross section of each shank portion, taken parallel to the base in the mid-height region of the shank, having a width in the direction of the row, and a thickness in the direction perpendicular to the row, the width being approximately twice the thickness or more. Certain advantageous implementations of this aspect of the invention have one or more of the following characteristics. The loop member comprises a nonwoven material. The loop member is attached to the outer cover in the first opposite longitudinal end section and the fastening member is operably associated with the second opposite longitudinal end section. Preferably, the garment has a longitudinal axis and the fastener elements are oriented parallel to the longitudinal axis of the garment.

According to another aspect of the invention with respect to the disposable absorbent press, each of the fastener elements comprises a portion of a rod attached at one end to the base, the rod being inclined at a substantially acute angle relative to the base, in the direction of the respective stack of the fastener element and lying substantially only in the planes aligned with its respective row. At least some of the elements also comprise a portion of fiber coupling plate disposed at the outermost, opposite end of the rod portion, the plate portion extending transversely to the direction of the respective row to form a protruding portion. In preferred embodiments of the aspect of the invention, a cross section of each portion of the rod, taken parallel to the base, has a width in the direction of the row and a thickness in the direction perpendicular to the row, the width being substantially greater than The spesor. Certain advantageous implementations of both aspects of the invention include that substantially all fastener elements include portions of plates.

BRIEF DESCRIPTION OF THE DRAWINGS Figures 1 and 2 are side elevational and plan views, respectively, showing one embodiment of a hook-shaped fastening member; Figures 1a, 1b, and 1c are side elevational, extreme and plan views, respectively, showing an individual fastener member of the fastener member in Figure 1; Figure 3 is a schematic representation of an assembly line where the fastener members, as shown in Figures 1 and 2, are applied to diapers; Figure 3a is an exploded portion of Figure 3 showing the orientation of the fastener elements on the diaper; Figure 4 illustrates the direction of tension applied to fasteners during normal use; Figure 5 is a schematic view of "fixing window", illustrating the coupling of a hook type fastener element with a nonwoven loop member, while Figures 5a, 5b and 5c are sequential diagrams illustrating the coupling of a hook-type fastener element with a loop of a non-woven fabric. Figure 6 is a schematic representation of the manufacturing process used to make hook fastener members. Figures 6a, 6b and 6c are side elevation views showing preforms of the fastener element used to make hook-shaped fastener members. Figures 7 and 8 are views in lateral elevation and in plan, respectively, showing a second embodiment of a hook fastener member. Figure 7a is a detailed side elevational view showing a fastener member of the fastener member of Figure 7. Figures 9 and 10 are side and plan elevation views, respectively, showing a third embodiment of a hook-shaped fastener member. . Figure 9a is a detailed side elevational view showing a fastener member of the fastener member of Figure 10. Figures 11 and 12 are side and plan elevation views, respectively, of a fourth embodiment of a hook-shaped fastener member. .

MODALITIES A preferred embodiment 110 of a hook fastener member, particularly useful in disposable diapers, is shown in Figures 1, 1a, 1b, 1c and 2. The hook-shaped fastening member consists of a base sheet 112 and multiple parallel rows. of integrally molded hook-shaped fastener elements 114 extending from the base sheet. Although only three rows are shown in the various figures, it should be understood that the fastened member may comprise several rows. As shown in greater detail in Figures 1a-1c, each fastener element of Figure 1 has a stem portion 116 of uniform thickness having flat vertical sides 116a116b which extend normal to the plane of the base sheet 112. Attached to the upper end of the rod is a hook-shaped reintroduction portion 117 which couples loops or fibers. In the upper part of the fastener is attached a portion of generally thin disc-shaped external plate 118 oriented substantially parallel to the base sheet. The reintroduction hook-shaped portion curves over and down towards the base sheet from the upper end of the rod portion 116 to define a fiber retention depression 119 on the underside of the hook-shaped portion. . The shank portion in lateral elevation, as seen in Figure 1a, tapers outward from a broad base to a relatively narrow external portion in the region of the depression 119. The fastener elements are generally aligned in multiple rows parallel to each other. flat sides of the individual elements, and the outer plate portion of each fastener element has transversely extending portions, for removing the sides 116a, 116b of the fastener element (Figures-1b, 1c, 2). In this preferred embodiment, the edge surfaces 123, 125 of the stem portion form angles? -? and 2 2 relative to the base sheet, respectively, which are substantially greater than 90 °. Preferably,? I and? 2 are between about 30 and 160 °. Most preferably, each is approximately 115 ° and 125 °, respectively. The formation of the rod portion so that the edges are straight or inclined inward allows the preform to be more easily removed from the molding roller 50 since the hook-shaped portion 117 can more easily pass through the portion of the former. molding roll where the portion of the rod is formed. To be used in an important application for the new fastener, together with non-woven loop members, fastener elements are generally very small. Therefore, the height 130 of the fastener element 114 is preferably between about 0.0127 cm and about 0.0762 cm, about 0.0381 cm being most preferred. In addition, the width of the base 126, that is, the width of the rod portion, taken parallel to the base sheet 112 to the level where the rod portion joins the base sheet, bypassing the chamfers 128a and 128b, preferably it is between about 0.0254 cm and about 0.0635 cm, with about 0.04318 cm being very preferred. In addition, the fastener elements are provided in a relatively high density, for example, from about 500 to about 4,000, alternatively about 1,000 to 2,500, alternatively about 1,500 to 2,000 fastener elements per cm 2. For example, as shown in Figure 2, the elements are preferably separated in a lateral form at a distance 135 of about 0.02032 cm, and the rod portions 116 preferably have a thickness 136 of about 0.01524 linear cm. This produces a full-width density of approximately 71 fasteners per centimeter. In the longitudinal direction, there are preferably approximately 24 fastener elements per 2.54 linear cm. In this way, preferably there is an order of 1700 fastener elements per 2.54 cm2 in this preferred embodiment. A distinct aspect of the hook-shaped fastener element 114 is the presence of the portion of the plate portion 118. This aspect contributes to the formation of the hook fastener 110 particularly useful for coupling the loops of non-woven fabrics in general. and, in particular, the non-woven fluff fibers that are desired for use in disposable diapers. As shown in Figures 3 and 3a, disposable diapers 10 are commonly made on an assembly line with the holding tabs 12 extending sideways, perpendicular to the direction in which the diaper travels. The hook-shaped fastening member is provided on the large rollers 14 of hook fastener tapes. As explained below, the hook fastener tapes are made using a rotating molding roll where the hook elements are aligned with the circumference of the roll. As a result of that process, the hook-shaped fastener elements are aligned along the longitudinal direction of the fastener tapes. For manufacturing efficiency, the hook fastener tapes can be wound and fed running parallel to the line of the diapers. As each diaper passes the appropriate station, a joining apparatus 16, such as an ultrasonic welder, attaches a patch 18 of hook fastening material to each of the fastening tabs 12. As a result, the hook fastener elements are oriented parallel to the longitudinal axis 20 of the diapers, as shown in greater detail in Figure 3a. Alternatively, the fastening tabs 12 having the hook fastening material 18 attached thereto, can be formed in a separate process and the fastening tab joined to the diaper during the diaper manufacturing process. Said separate process is described in, for example, PCT application publication No. WO95 / 05140 which is incorporated herein by reference. When the diaper is placed on the child, it will have the configuration and orientation shown in Figure 4. In this way, when the fastening tabs 12 are coupled with the matching nonwoven tie member strip 22, the applied tension forces S the base of the fastening member and the loop member will act perpendicular to the orientation of the hook-shaped fastening elements, thus subjecting the closure to lateral shear stresses, as suggested in Figure 5. During clamping, the clamping tongues 12 they will slide slightly relative to the loop member strip 22. This is indicated schematically in Figure 5, which, exaggerated for purposes of illustration, shows the edge of the holding tab 12 in three successive locations 5a, 5b and 5c . In Figure 5 there is a representation of "fastening window" of an individual fastener element 114 surrounded by the surface fibers 23 of the non-woven tie member 22, as can be seen from below the fastener element. As shown in Figures 5a, 5b and 5c, which correspond in Figure 5 to locations 5a, 5b and 5c, respectively, as the fastener member slides slightly, it is shown to intercept a surface fiber 23, which is illustrated as being anchored to the member 12. During the initial sliding action, a protruding portion of the thin outer plate 118 of the fastener member slides below the low laid surface fiber 23 (Figure 5b), as an initial part. of the coupling action. As the relative movement continues, the fiber is guided by the chamfers 120 between the plate portion 118 and the hook-shaped portion 117 and the rod portion (see Figure 1b). The fiber 23 is thus guided below the hook-shaped portion 117 and is secured in the reintroduction fiber retention depression 119 to more securely attach the fastener member to the fiber. In Figure 5b, the end of the hook element is shown to have been flexed laterally by the coupling force with the loop member (shown exaggeratedly for purposes of illustration). This bending, facilitated by the relative thinness (dimension 136) of the element and the off-center load on the head of the fastener element is shown to contribute to the effectiveness of the coupling action. As shown in Figure 6, a preferred method for making said hook-type fastener members with the flat upper part comprises extruding molten resin into the nozzle formed between a cold mold roll 50 and a pressure application roll 52, as taught by Fischer, patent of E.U.A. No. 4,794,028, fully incorporated herein by reference. The cold mold roll has cavities around its periphery which are configured to produce fastener element preforms 154, which are shown in greater detail in Figure 6a. Since the preforms of the fastener element face in opposite directions, the preforms of the fastener element in the middle of the columns are oriented along the path direction of the belt, and the preforms of the fastener element in the other half of the columns. they are oriented opposite to the path direction of the tape. The preforms of the fastener element that are oriented against the path direction can leave the mold cavities of the roller in motion without significant flexion, but the preforms of the fastener element that are oriented along the path direction flex around the edges of the mold cavities as they are extracted from the cavities. This deforms them slightly, causing them to extend higher from the base sheet and at an angle slightly steeper than the preforms that are oriented along the path direction. To make the two sets of preforms more uniform, the preforms are passed under a slap roll 56, the distance of which, relative to the wrap roller 57, is adjustable. The kick roller pushes the highest and steepest preforms back to the same level in relation to the base sheet, as the level of the preforms that are oriented with the direction of the tape path. This leveling will allow a more uniform formation of the plate portions 118, discussed below. The knock roll 56 is located near the position where the preforms are removed from the cavities so that the preforms remain slightly soft and permanently deformable as they pass under the kick roll and thus retain their new shape. Alternatively, to form the plate portion only on some of the fastener preforms, the kick roller 56 can be removed. In this way, the elements oriented against the path direction are left in an elongated, higher state and can be deformed to form plate portions 118 without forming plate portions on the elements oriented along the path direction. After the preforms have cooled sufficiently to be strong enough to withstand the pressure applied to them without deforming, the thin outer plate portions 118 are formed, as in station 58. The plate portions can be formed either in line with the molding process, that is, as part of a continuous operation, or they can be formed in a separate, post-training operation at a later time. In this way, the fastener tape is shown as broken in Figure 6 to indicate this capacity for variation. To form the outer plate portions, the tape of the fastener element preforms is passed through the gap 60 between a hot thermoforming roll 62 and a support roll 64, the width of the gap of which is adjustable. The roller 62 is heated to a selected temperature sufficient to thermally reform the elements. In this way, as the preforms come into contact with the hot thermoforming roller 62, their outer ends 155 (Figure 6a) are thermoformed by the action of the rollers to provide the disc-shaped plate portions 118 of the fastener elements 114. The selected temperature of the roller 62 depends on the thermal properties of the particular resin that is being used to make the fastener member and the selected operating speed. Currently, the covering material for disposable diapers is usually polypropylene. In certain applications, nylon or other materials could also be appropriate. To ensure a good joint when the hook fastener members are attached to the fastener tabs of the diapers 12, the hook fastener member is preferably also made of polypropylene. In this case, the roller 62 is heated to a surface temperature of approximately 176.6 ° C, and is operated on a demonstration line at a linear speed of approximately 3.3538 meters per minute (in production much higher speeds will be used). The preforms reach the roller 62 almost tangentially. This results in a temperature on the hook surface, which is approximately equal to the melting temperature of the polypropylene resin, and causes the end of the preform to be softened to the point of being permanently deformable under pressure, without causing melting. to a highly fluid state. Of course, it is envisaged that other plastics will be used to form said flat top hook fastener members. The selected material preferably has a relatively low melt flow index, which is a measure of the viscosity of the resin when it melts. Resins with fractional melt flow rates, ie, indexes that are less than 10, are highly preferred, although under certain circumstances and hook designs, resins with melt flow rates as high as 5.0 or 10.0, or even larger, can be used by carefully balancing the steps of the procedure. The temperature of the roller 62 and the linear velocity through the station 58 is selected to impart a temperature to the hook surface, which makes the selected resin moldable. For polypropylene, as noted above, it was found that a temperature of 176.6 ° C was appropriate. In addition, additional support rollers and the like can be used to increase the arc of the roller 62, with which the preforms have contact, thus increasing the heating time for a given linear velocity. The width of the gap 60 between the thermoforming roll and the support roll 74 is adjusted to obtain the appropriate height 130 (Figure 1a) of the final fastener elements, the height 130 in turn being a function of the height of the preforms of the bra element. With respect to the amount by which the upper parts of the hook elements are thermoformed, and, therefore, with respect to the height 30, it is important that the outer ends are not deformed so much in order to impart the geometry of the hook-shaped portion 117 or the ability of the fastener element to engage and retain the fibers of the loop member. In general, the tops of the elements are thermoformed through an amount to produce an effective projection of the plate portion, i.e., the amount by which the plate portion extends beyond (salts) of both sides 116a 116b of the rod portion of the fastener element. Depending on the conditions of use, it is advantageous that the amount of protrusion falls within the range of 5 to 50% of the thickness of the hook element; in other conditions with the scale of 10 to 30%; and in other conditions, within the range of 15 to 25%. In certain preferred cases, the projections of about 25% of the thickness of the rod portion. Thus, in preferred cases, the width dimension 138 of the plate portions (Figure 2) is approximately 1.5 to 2.0 times the thickness 136 of the rod portion and the vertical thickness 139 of the plate portion 118 is between about 0.2 and 0.4 times the thickness 136 of the rod portion. The longitudinal dimension of the plate portion, in general, will be a little larger than the width dimension, and it is generally allowed to be any dimension resulting from the thermoforming of the plate portion sufficiently to obtain the desired effective lateral protrusion and The height of "hook." The thickness of the plate was 0.00508 cm and the protrusion was 0.0076-0.01016 cm.A preferred thickness scale is 0.000254 to 0.0127 cm, and in certain cases, a very preferred scale is 0.00254 a 0.01016 cm Finally, with respect to the manufacturing process, in order that the plate portions 118 are substantially parallel to the base of the hook fastener member, it is preferred that the hot roller 62 and the support roller 64 rotate at speeds so that their tangential surface velocities substantially coincide with the feeding speed of the fastening tape, otherwise the plate portions will be strained by, or dragged along, the hot roller and will deform. Another preferred embodiment 210 of the flat-top hook fastening member is shown in Figures 7, 7a and 8. This embodiment has a base sheet 212 from which a plurality of discrete fastener elements 214 extends, with upper part piaña. Each fastener element 214 has a chamfered stem portion 216, having flat sides similar to the sides 116a, 116b of Figure 1b. These portions are integrally molded with and extend from the base sheet. Each fastener element also has a disc-type outer plate portion, 218, generally planar, located at the outer end 220 of the rod portion leaving the flat sides of the chamfered stem and a hook-shaped portion 217 of introduction that depends on the outer plate portion. The plate portion 218 extends generally parallel to the base sheet 212. As shown in more detail in Figure 7a, the general configuration of the rod portion 216 of the fastener elements can be characterized by two parameters. First, it is chamfered relative to the base 212 since the surface 222 of the rod portion on the side on which the hook depression is formed, forms an acute inclined angle a relative to the base. Preferably, the inclined angle a is between about 30 ° and about 80 °; most preferably, a is between about 40 and 60 °, and preferably a is about 45 °. The second parameter to characterize the configuration of the rod portion is the width 226 of the base, which, as before, is the width of the rod portion, taken parallel to the base sheet 212, wherein the rod portion join the base, bypassing the chamfers 228a and 228b. Preferably, the width of the base is between about 0.0254 cm and about 0.018 cm; most preferably the width of the base is about 0.03556 cm. Finally, other parameters characterizing the entire fastener element 214 are the height 230 of the fastener element, as measured from the upper surface of the base sheet 212 towards the upper surface of the piaca portion 218, and the width dimension 238 of the plate portion. The thickness of the rod portion 236 is preferably the same as for the first embodiment, for example, about 0.01524 cm. Preferably, the height is between about 0.0127 and about 0.0762 cm; most preferably the height is around 0.0381 cm. As shown in Figures 7 and 8, the fastener elements 214 are disposed on the base sheet 212 with the fasteners in a column all slanted in one direction and the fasteners in the adjacent column all slanted in the opposite direction. The spacing and density of the fastener elements is approximately equal to the spacing and density described above with respect to the first embodiment. The pattern of the flat top hook fastener member of Figures 7 and 8 is also made through the procedure shown in Figure 6. The hook preforms 254 are configured as shown in Figure 6b, which, like the preforms 154 shown in Figure 6a, generally have the shape of a hook, although inclined relative to the base. Other profiles can also be used for an inclined hook preform 254. See, for example, Figure 22 of Provost et al., U.S. No. 4,984,339, which is incorporated herein by reference. The inclined relationship of the fastener elements of Figures 7 and 9 provides a longer fastener and a greater degree of off-center load when subjected to conditions as presented in Figure 4 of the preceding embodiment. As a result, under loading conditions presented in Figure 4, a greater degree of elastic deflection of the hook end may occur which may increase the fiber coupling effectiveness of the hook elements. A third preferred embodiment 310 of a flat top hook fastener member is shown in Figures 9, 9a and 10. This embodiment is similar to the second embodiment 210 discussed above, the outer plate coming out of the flat sides of the chamfered stem. The main difference in this embodiment is that the intersection of the inclined rod and the outer plate 318 defines a non-introductory fiber coupling hook. This allows the protruding plate portion 318 to slide below the loop members with an extremely low lay-up fluff. The third embodiment can also be manufactured by the method shown in Figure 6, this time using simple tapered fastener element preforms 354 without reintroduction hooks, as shown in Figure 6. As described above, when the element preforms When the fastener faces in opposite directions, the preforms of the fastener element which are oriented along the direction of travel are inclined around the edges of the mold cavities as they are removed. This causes these preforms to extend higher from the base sheet and at an angle slightly steeper than the preforms that are oriented along the path direction. In certain cases, it is desirable to form the outer plate portions 118 only on some of the fastener preforms. This can be achieved, for example, by not passing the fastener preforms under the stroke roller 56. In this way, since the fastener preforms have different heights from the base sheet, passing the preforms of the fastener element to Through the gap 60 between the hot roll 62 and the support roll 64 the disc-shaped plate portions 118 will be formed only on those fastener preforms that extend beyond the base sheet (those preforms which are oriented to along the path direction), as shown in Figures 11 and 12. For some applications, having some of the preforms of the fastener element has the disc-shaped plate portions 118 and others do not possess the plate portions and it provides a more satisfactory balance of holding properties (such as the desired balance of shear and shear properties). In other modalities, the fastener preforms are formed to have different heights from the base sheet independent of their orientation during manufacture. This is achieved through the use of mold cavities having different depths during the formation of the preforms. With such preforms, in one embodiment, flat tops are provided only on those preforms that have the greatest height. The formation of the fastener element preforms to have different heights from the base sheet in some cases allows greater control over the percentage of elements having "flat top" parts. It is possible to form preforms of the fastener element with two, three or more different heights from the base sheet.

Other embodiments are within the scope of the following claims.

Claims (32)

1. A fastener member comprising: a base and multiple rows of fastener elements extending from the base and exposed for engagement with a fabric, each fastener element integrally molded with and extending from the base to a distal end, each fastener element molded to exit from the base. the base in the direction of the rows to allow the coupling of fabric fibers between the fastening element, according to the molding, and the base; at least one of the fastener elements each having a portion of fiber coupling plate at its distal end, the plate portion lying generally parallel to the base and exiting the base in a direction perpendicular to its row of elements to allow the additional coupling of the fabric fibers between the plate portion and the base.

2. The fastening member according to claim 1, wherein the fastening members with plate portions each have a hook-shaped reintroduction portion having a free end, said plate portion having a thickness, in one direction. normal to the base, which is less than the thickness, in a direction normal to the base, of the free end of the hook-shaped portion.

3. The fastening member according to claim 1, wherein the fastening elements are formed of thermoplastic resin, said plate portions each comprising a post-formed structure formed in resin of a molded fastener element.

4. The fastening member according to claim 1, wherein the protruding portions of substantially all of the fastening elements, in a first row extend in a first direction and substantially all of the fastening elements in a second close row extend in a second direction opposite to the first address.

5. The fastening member according to claim 4, wherein substantially all fastener elements in the first row each include a plate portion, and substantially all fastener elements in the second close row do not include the plate portions.

6. The fastening member according to claim 1, wherein the fastening elements with the plate portions each have substantially flat wide sides, a cross section of each fastening element, taken parallel to the base at the average height of the element. fastener, having a width in the direction of the rows and a thickness in the direction perpendicular to the rows, said width being at least approximately twice the thickness.

7. The fastening member according to claim 6, wherein the width tapers inward from the base.

8. - The fastening member according to claim 1, wherein the fastening elements each define a central axis, which is inclined, in the direction of the rows, at an acute angle relative to the base.

9. The fastener member according to claim 1, wherein substantially all fastener elements each include a plate portion.

10. The fastener member comprising: a base, and multiple rows of molded fastener elements extending from the base, each fastener element comprising a portion of stem integrally molded with the base, said portion of the stem being inclined at an acute angle with respect to to the base to exit the base in the direction of the respective row of the fastener element and to lie substantially only in planes aligned with its respective row; at least some of the fastener elements each having a portion of fiber coupling plate disposed at its outermost end, said plate portions extending transversely to the direction of extension of the rows to form projecting portions on two opposite sides of their elements respective bras.

11. The fastening member according to claim 10, wherein substantially all fastener elements each include a plate portion.

12. The fastening member according to claim 10, wherein a cross section of each portion of the rod, taken parallel to the base, has a width in the direction of extension of the rows and a thickness in the direction perpendicular to the extension of the rows, said width being substantially greater than the thickness.

13. A closure comprising the fastening member according to claim 6 or claim 12 and a non-woven fabric coupled thereto, the base of said fastener and said non-woven fabric being under tension in opposite directions so that the elements Fasteners are subjected to and resist shear stresses caused by the tension load, the tension acting in the thickness direction.

14. A method for making fastener members, comprising: extruding a molten resin and applying said resin to a mold roll having cavities formed around its perimeter; applying pressure to said resin to cause the resin to fill the cavities, thereby forming a clamping member preform, said clamping member preform comprising a base and a plurality of discrete clamping element preforms aligned in at least one row, integrally molded with and extending from the base, said fastener element preforms comprising rod portions with outer ends that lie on the base substantially only in planes aligned with its row; separating said preforms of fastener member from the molding roll; and flattening the outermost portions of at least some of the fastener element preforms, thereby forming generally plate-like portions, which are disposed at the outermost ends and exit the base in a direction perpendicular to its row.

15. The method according to claim 14, wherein the flattening comprises heating the outermost ends of at least some of the fastener element preforms to a temperature that is close to the melting temperature of the resin, and Apply pressure to the outermost ends.

16. The method according to claim 15, wherein the heating and the application of pressure to the outermost ends are carried out in an individual step.

17. The method according to claim 16, wherein the individual step comprises passing the fastener member preforms through a hot roll and compressing at least some of the fastener preforms against the hot roll.

18. The method according to claim 14, wherein the formation of the fastener member preforms and the flattening of the outermost ends of at least one of the preforms comprises a continuous, individual procedure.

19. - The method according to claim 14, wherein the outermost ends of at least some of the preforms of the fastener element are flattened in a post-processing operation.

20. The method according to claim 14, characterized in that it further comprises, before flattening, correcting the differences in the heights of the preforms of the fastener caused by the separation step, to ensure a generally uniform height.

21. The method according to claim 20, wherein the correction step comprises compressing a striking roller against the outermost ends of the fastener preforms.

22. The method according to claim 14, characterized in that it comprises flattening the outermost portion of substantially all the preforms of fastener element.

23. The product formed by the method of claim 14. 24.- A method for improving the coupling capacity of a hook-type fastening member with a non-woven loop-type fastening member, said fastening member hook type comprising a base and a multitude of fastener elements generally hooked, integrally molded with and extending from the base in a given direction or in that direction or in an opposite direction, and lying only in planes parallel with the direction given and perpendicular to the base, said method comprises flattening the outermost ends of at least some of the fastener elements for forming generally plate-like portions arranged at the outermost ends and generally parallel to the base and perpendicular to the planes. 25. A disposable absorbent garment comprising: an outer covering; a body side lining; an absorbent core located between the outer shell and the body side shell; a loop member operably associated with the garment; and a fastener member operably associated with the garment for detachable engagement with the tie member, the fastening member comprising: a base and multiple rows of fastener elements extending from the base and exposed for engagement with a fabric, each fastener element integrally molded with and extending from the base toward a distal end, each fastener element molded to exit the base in the direction of the rows to allow coupling of the fabric fibers between the fastening element, according to molding, and the base; at least some of the fastener elements each having a portion of fiber coupling plate at its distal end, the plate portion lying generally parallel to the base and exiting the base in a direction perpendicular to its respective row of elements for allow additional coupling of fabric fibers between the plate portion and the base. 26.- The garment according to claim 25, wherein the fastening elements with the plate portions each have a reintroduction hook forming portion having a free end, said plate portion having a thickness, in one direction normal to the base, which is less than the thickness, in a direction normal to the base, of the free end of the hook forming portion. 27. The garment according to claim 25, wherein the fastening elements with the plate portions each have substantially flat wide sides, a cross section of each fastener element, taken parallel to the base at the average height of the fastening element. having a width in the direction of the rows and a thickness in the direction perpendicular to the rows, said width being at least approximately twice the thickness. 28. A disposable absorbent garment comprising: an outer covering; a body side lining; an absorbent core located between the external cover and the body side lining, a loop member operably associated with the garment; and a fastener member operably associated with the garment for detachable engagement with the loop member, the fastening member comprising: a base, and multiple rows of molded fastener elements extending from the base, each fastener element comprising a portion of integrally molded stem with the base, the portion of the rod being inclined at an acute angle relative to the base to exit the base in the direction of the respective row of said fastening element; at least some of the fastener elements each having a portion of fiber coupling plate disposed at its outermost end, the plate portions extending transversely to the extension direction of the rows to form protruding portions on two opposite sides of its respective fastener elements. 29. The garment according to claim 28, wherein a cross section of said rod portion, taken parallel to the base, has a width in the direction of extension of the rows and a thickness in the direction perpendicular to the extension. of the rows, said width being substantially greater than the thickness. 30. The garment according to claim 25 or claim 28, wherein the loop member comprises a nonwoven material. 31. The garment according to claim 25 or claim 28, having a longitudinal axis, wherein the fastening elements are oriented parallel to the longitudinal axis of the garment. 32. The garment according to claim 25 or claim 28, wherein substantially all fastener elements each include a plate portion.