Patent Publication Number: US-2007110952-A1

Title: Touch fastener components carrying indicia, and methods of making the same

Description:
TECHNICAL FIELD  
      This disclosure generally relates to touch fastener components carrying indicia, and to methods of making the same.  
     BACKGROUND  
      Early male touch fastener products were generally woven materials, with hooks being formed by cutting filament loops. More recently, arrays of small fastener elements have been formed by molding the fastener elements, or at least the stems of the elements, to form an interconnected sheet of material. It is often difficult to ascertain a source of a fastener just by looking at the product.  
     SUMMARY  
      Generally, the disclosure relates to touch fastener components carrying indicia, e.g., molded indicia, and to methods of making the same.  
      In one aspect, the disclosure features touch fastener components that include a sheet-form base and an array of touch fastener elements on an engaging side of the sheet-form base. Each touch fastener element includes a stem extending outwardly from the sheet-form base and an engageable head extending from a distal end of the stem. The touch fastener component carries molded indicia on a surface thereof, the molded indicia including features smaller than the touch fastener elements and visible from the engaging side of the sheet-form base.  
      In some implementations, the touch fastener element stems are integral with the sheet-form base.  
      The indicia can be, e.g., in the form of molded projections extending outwardly from the surface of the touch fastener component. For example, in such instances, the molded projections can extend outwardly from the surface a maximum distance of less than 0.0010 inch (0.025 mm), measured perpendicular to the surface in a direction of extension.  
      The indicia can be, e.g., in the form of small cavities or recesses extending inwardly from the surface into the fastener component. For example, in such instances, the recesses can extend inwardly from the surface a maximum distance of less than 0.0010 inch (0.025 mm), measured perpendicular to the surface in a direction of extension.  
      The indicia can be, e.g., carried on sides of the touch fastener elements and/or carried on a sheet-form base surface from which the fastener element stems extend.  
      In some implementations, each fastener element has two heads extending in substantially opposite directions. In other implementations, that touch fastener elements are in the form of a hook, e.g., a J-style hook.  
      The engageable head and stem of each fastener element can, e.g., together form a unitary molded structure. The engageable head can have, e.g., a surface of resin evidencing having been cooled against a mold surface.  
      In a specific implementation, each engageable head includes multiple, discrete engaging prongs, and the indicia extend from a distal surface of at least some of the engaging prongs.  
      In some embodiments, each fastener element has an overall height, measured perpendicular to the sheet-form base in a direction of extension, of between 0.0050 inch (0.13 mm) and 0.10 inch (2.5 mm). The fastener elements can be, e.g., arranged in a density of at least 100 fastener elements per square inch (15.50 fastener elements per square centimeter). If desired, lateral sides of each fastener element can be, e.g., substantially parallel.  
      If desired, the touch fastener components can, e.g., further include a backing material laminated to a non-engaging side of the sheet-form base opposite the touch fastener elements. Such implementations can be advantageous when it is desired to attach, e.g., by stitching or sewing, the touch fastener components on a garment.  
      The indicia can be, e.g., disposed between adjacent rows of touch fastener elements and/or disposed between fastener elements in a given row or rows.  
      In some implementations, indicia are configured to indicate a source of goods, text, and/or graphics.  
      In another aspect, the disclosure features methods of a making touch fastener components having a sheet-form base and an array of fastener elements extending therefrom. The methods include forming from a resin an array of fastener elements with stems extending outwardly from an engaging side of a sheet-form base and forming indicia on a surface of the touch fastener, the indicia including features that are smaller than the fastener elements and that are visible from the engaging side of the sheet-form base.  
      In some implementations, the indicia are formed by molding the resin. The indicia can be, e.g., formed as the fastener elements are formed of the resin.  
      In some embodiments, the indicia are formed by being marked on a surface of the formed touch fastener. For example, marking can be accomplished by using a printer, e.g., an inkjet printer, or by a laser, e.g., a C 0   2  laser.  
      Any of the methods described herein can be, e.g., performed in a continuous process to produce a lengthwise-continuous fastener tape.  
      In some embodiments, the stems of the fastener elements are formed in cavities extending inwardly from a peripheral surface of a rotating mold roll. For example, the rotating mold roll can be adjacent a counter-rotating pressure roll. In some implementations, the forming of the fastener elements and the forming of the indicia are performed by introducing molten resin to the peripheral surface of the rotating mold roll; applying sufficient pressure to force the resin into the cavities to mold the fastener element stems, while forming the sheet-form base of resin on the peripheral surface of the mold roll; cooling the resin in the cavities; and then stripping the sheet-form base from the peripheral surface of the mold roll, thereby pulling the molded fastener element stems formed in the cavities from their respective cavities. The mold roll includes indicia-forming features on a surface thereof, the indicia-forming features being configured to form the indicia on the surface on the engaging side of the sheet-form base. In such implementations, the indicia-forming features can be, e.g., in the form of recesses extending inwardly from the peripheral surface of the mold roll. The mold roll cavities can be shaped to form releasably engageable fastener elements. Such implementations can further include deforming terminal ends of the molded fastener element stems between a conforming roll and a supporting roll to form engageable heads that overhang sides of the stems. If desired, the conforming roll can, e.g., include indicia-forming features on a surface thereof, the indicia-forming features being configured to form the indicia on the heads.  
      Aspects and/or implementations may have one or more of the following advantages. Indicia can provide useful information about the touch fastener component, e.g., its source, or the material from which it is formed. Indicia indicating the source of goods can make it easier to ascertain the authenticity of a product carrying the indicia. Indicia can also indicate the date in which the fastener component was produced, and from which apparatus, e.g., mold, they were produced, making the product more traceable with respect to geographic location and date of manufacture.  
      Other features and advantages of the disclosure will be apparent from the following detailed description, and from the claims. 
    
    
     DESCRIPTION OF DRAWINGS  
       FIG. 1  is a perspective view of a portion of a male touch fastener carrying indicia.  
       FIG. 1A  is a highly enlarged perspective view of a hook having indicia on a side surface.  
       FIG. 1B  is a cross-sectional view of the hook of  FIG. 1A , taken along  1 B- 1 B.  
       FIG. 2  is a schematic side view of a method for making the male touch fastener of  FIG. 1  and others.  
       FIG. 3  is a highly enlarged perspective view of several mold rings having indicia-forming features.  
       FIG. 4  is a side view of an alternative process for making the male touch fastener of  FIG. 1  and others.  
       FIG. 5  is a perspective view of a castellated preform carrying indicia on a side surface.  
       FIG. 6  is a side view of an apparatus for forming engageable heads on distal ends of the castellated perform of  FIG. 5  and others.  
       FIG. 6A  is a perspective view of a portion of a conforming roll having indicia-forming features.  
       FIG. 7  is a top view of a portion of a male touch fastener having discrete engageable prongs made by deforming distal ends of castellated performs.  
       FIG. 7A  is an enlarged top view of a touch fastener element having engaging prongs which carry indicia on a top surface thereof.  
       FIG. 8  is a perspective view of a palm tree hook carrying indicia extending on a side surface. 
    
    
     DETAILED DESCRIPTION  
      Referring to  FIGS. 1, 1A  and  1 B, a male touch fastener  10  includes a sheet-form base  12  and an array of molded male touch fastener elements  14  on an engaging side  16  of the sheet-form base  12 . Each touch fastener element  14  includes a stem  13  extending outwardly from and integral with the sheet-form base  12  and an engageable head  15  extending from a distal end of the stem. The touch fastener  10  carries indicia I on a surface thereof that are visible from the engaging side  16  of the sheet-form base  12 . Generally, the indicia include features that are smaller than the touch fastener elements. As shown, the male touch fastener elements  14  are arranged in rows R 1 , R 2 , R 3 , . . . R N , with a spacing S 1 , S 2  . . . S N−1  between adjacent rows. In the particular implementation shown, some of the indicia I are sized to fit between adjacent rows of touch fastener elements that are in the shape of J-hooks, each hook having lateral sides that are substantially parallel. Also as shown, the engageable side of each head in a particular row, e.g., R 1 , faces a single direction, the direction being substantially opposite in adjacent rows, e.g., R 1  and R 2 .  
      Generally the indicia I provide useful information. For example, the indicia can provide information about a touch fastener product, e.g., its source, the material from which it is made, the date it was made, molds from which the fastener was produced, and/or the geographic location of production. Indicia I indicating the source of goods are often advantageous because they make it easier to ascertain the authenticity of a product. In some implementations, the indicia I are arranged to define text (e.g., words and/or numbers), or graphics (e.g., logos and/or pictograms). In specific implementations, the text identifies a mold number, a production date, or a geographic location of production.  
      The indicia I can, e.g., be molded. In such instances, the indicia I can be in the form of molded projections  21  extending outwardly from a lateral side  20  of each fastener element  14 , or in the form of molded projections  26  extending outwardly from a top surface  28  of the sheet-form base  12 . In such implementations, the molded projections  21  and/or  26  can extend outwardly from their respective surface, e.g., a maximum distance D ( FIG. 1B ) of less than 0.0010 inch (0.025 mm), less than 0.0005 inch (0.013 mm), or less than 0.00025 inch (0.0064 mm), measured perpendicular to the surface in the direction of extension.  
      In some embodiments, the fastener elements are arranged in a density of at least 100 fastener elements per square inch (15.50 fastener elements per square centimeter), e.g., more that 500, more than 750, more than 1500, more than 2500, or more than 5000 fastener elements per square inch (77.50, 116.24, 232.49, 387.48, or more than 774.95 fastener elements per square centimeter, respectively). Any of these embodiments can have less than 7000 fastener elements per square inch (1085.00 fastener elements per square centimeter).  
      The fastener elements can extend a distance H ( FIG. 1B ) from the sheet-form of, e.g., less than 0.10 inch (2.54 mm), less than 0.050 inch (1.27 mm), less than 0.030 inch (0.76 mm), less than 0.020 inch (0.51 mm), or less than 0.010 inch (0.25 mm), measured perpendicular to the sheet-form base from the top surface  28  to a maximum extension of the head above the sheet-form base  12 .  
      In some implementations, it is desirable for the fastener component to have a backing material  25  laminated to a non-engaging side  23  of the sheet-form base  12  opposite the touch fastener elements. This can be useful, e.g., when it is to be fastened to an article of clothing.  
      Generally, the touch fastener components can be made by forming from a resin, e.g., a thermoplastic resin, an array of fastener elements with stems extending outwardly from an engaging side of a sheet-form base and forming indicia, e.g., by marking or molding, on a surface of the touch fastener. The indicia include features that are smaller than the fastener elements and that are visible from the engaging side of the sheet-form base.  
      Referring also now to  FIGS. 2 and 3 , touch fastener  10  can be made, e.g., by extruding thermoplastic resin in the form of a sheet  30  from an extruder  32  and introducing the sheet  30  into a nip  38  formed between a pressure roll  40  and a counter-rotating mold roll  42  that defines fastener element-shaped cavities  48  that extend inwardly from its surface  52 . Mold roll  42  includes indicia-forming features M that extend inwardly from a surface, e.g., an outer surface (like indicia-forming features  66 ) or inner surface (like indicia-forming features  68 ). Pressure in the nip  38  causes the resin to enter the fastener element shaped forming cavities  48  and the indicia-forming features M, respectively, to form fastener elements  14  and indicia I. The thermoplastic resin is cooled as it proceeds along the periphery of the mold roll  42 , solidifying the fastener elements  14 . The touch fastener  10  is stripped from the mold  42  by stripper roll  50 .  
      In such implementations, the mold roll  42  includes a face-to-face assembly of thin, circular plates or rings that are, e.g., 0.003 inch to 0.250 inch (0.0762 mm-6.35 mm) thick, some rings  60  having cutouts in their periphery which define mold cavities and other rings  62  serving to close the open sides of the mold cavities and serve as spacers, defining the spacing (discussed above) between adjacent fastener element rows. Rings  62  have indicia-forming features M that extend inwardly from a surface thereof. A fully “built up” mold roll can have a width, e.g., from 0.75 inch to about 6 inches (1.91 cm-15.24 cm) or more, and can have, e.g., from about 50 to 1000 or more individual rings.  
      When the indicia I are in the form of molded projections  21  extending outwardly from a side  20  of each fastener element  14 , the corresponding indicia-forming features M are relatively shallow cavities or recesses extending inwardly from a side surface of rings  62 . When the indicia I are in the form of molded projections  26  extending outwardly from the top surface  28  of the sheet-form base  12 , the corresponding indicia-forming features M are relatively shallow cavities or recesses extending inwardly from a peripheral surface  67  of the rings  62 . The relatively shallow inwardly extending indicia-forming features can be made by a variety of techniques, e.g., machining (e.g., computer-assisted machining), or engraving (e.g., computer-assisted engraving or laser engraving).  
      The thermoplastic resin can be, e.g., a polyolefin (e.g., a polyethylene or a polypropylene), a polyester (e.g., polyethylene terephthalate), or a polyamide (e.g., nylon 6, 6/12 or 6/10). It is often desirable to use a relatively low viscosity resin so as to fully replicate the indicia-forming features. For example, when a polyolefin is used, it is often desirable that the polyolefin have a melt flow rate that is, e.g., greater than 5.0 g/10 minutes (e.g., greater than 10.0 g/10 minutes, greater than 15.0, greater than 20.0, greater than 25.0, greater than 30.0, or even greater than 50.0 g/10 minutes), measured using ASTM D1238, 230° C./2.16 kg. In specific implementations, the resin is a 50:50 weight percent blend of a 20 melt flow rate (MFR) polypropylene and a 50 MFR polypropylene. Polypropylenes are available from Sunoco Chemical.  
      An alternate technique for molding touch fasteners carrying indicia I is shown in  FIG. 4 . The process is similar to that described above with reference to  FIGS. 2 and 3 , except only a mold roll  42  is used, i.e., no pressure roll  40  is necessary. Here, the extruder  32  is shaped to conform to the periphery of the mold roll and the molten resin  29  is introduced under pressure directly to a gap  70  formed between mold roll  42  and extruder  32 . The molded touch fastener is stripped from the mold cavities by a stripper roll  50 , as described above.  
      Referring back now to  FIGS. 1 and 2 , a laminated male touch fastener can be formed by introducing a backing material  25  from a supply  80  into the nip  38 , along with the resin. The heat and pressure in the nip  38  aids in the bonding of the backing material  25  to the resin  29 , while the fastener elements and indicia I are formed. The result can be a contiguous molded structure, without weld lines. In one useful implementation, backing material  25  is a loose knit scrim, such as Knit 3901 from Velcro USA in Manchester, N.H., although Velcro USA loop products 3900, 3905, and 3400 can also be employed. Knit 3901 is a 2 bar Tricot knit nylon fabric which generally must be brushed or napped before it can be employed as the functioning loop of a hook and loop closure. However, it has been found to function well as a reinforcement when at least partially encapsulated by, or bonded to, the base resin contiguous with the resin forming the hooks, without brushing or napping. Reinforcing the base with such a scrim can, e.g., improve the stitch tear strength of the product, providing a resin-base fastener product practical for attachment by stitching.  
      In some cases, the fastener elements are not molded in their final form. Referring to  FIG. 5 , straight-sided thermoformable preform member  100  extends upwardly from and is continuous with a base layer  101 . A distal end  105  of member  100  defines a plurality of parallel upwardly directed prongs  108  extending to respective terminal ends  109 . In this particular implementation, the prongs have no overhang of the base, and all side surfaces of the stems and prongs are parallel (except for a small draft angle). As shown, indicia I in the form of molded projections  121  extend outwardly from a side  126  of member  100 . In the particular implementation shown, there is a 2 by 3 pattern of upwardly directed prongs, each prong having in transverse cross-section (parallel to the base) that is rectangular.  
      Referring now to  FIG. 7 , from this pronged preform member  100 , fastener elements  120  having six discrete heads  110  can be formed by the application of appropriate heat and pressure to the terminal ends  109  of prongs  108 . If desired, heat and pressure can be applied such that the six discrete heads coalesce to form one relatively large head at the distal end  105  of member  100  (not shown). A large array of the fastener elements  120  form a sheet-form fastener product  130 .  
      Referring now as well to  FIG. 6 , in some implementations, sheet-form fastener  130  can be formed in an apparatus  150  by passing a preform sheet  140  that includes an array of members  100  under a heating device  160 , which heats the distal ends  105  of members  100 . In some implementations, the heating device  160  include a non-contact heat source  162  that is capable of quickly elevating the temperature of resin that is very close to the heat source without raising the temperature of material that is relatively further away from the heat source. Non-contact heat sources include, e.g., flame heaters, electrically heated nichrome wire, and radiant heater blocks. After distal ends  105  of members  100  have been heated, preform sheet  140  moves to conformation station  170 , at which time base sheet  140  passes between conformation roll  172  and drive roll  174 . Conformation roll  172  forms the prongs into a desired shape, while drive roll  174  advances the sheet material.  
      In some implementations, conformation roll  172  is a smooth cylindrical roll, so that upon deformation of the distal ends  109  of each prong  108 , a substantially flat upper surface is formed (as in  FIG. 7 ). Referring now to  FIGS. 6A and 7A , in some implementations, a conformation roll  201  can define a plurality of indicia-forming features in the form of shallow cavities or recesses  200  that extend inwardly from a peripheral surface  203 . Pressure between conformation roll  201  and drive roll  174  (FIG.  6 ) causes the molten thermoplastic resin at distal ends of prongs to enter the shallow cavities or recesses  200  to form indicia in the form of projections  210  that extend outwardly from each head  209 .  
      A number of implementations have been disclosed. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure.  
      For example, while implementations have been shown in which hooks are in the shape of a J, in some implementations, the hooks are palm tree-shaped hooks  240  ( FIG. 8 ), which have two heads  242  and  246  extending from a single stem  250 , and, thus, are engageable in two directions.  
      While implementations have been shown in which a single stem has six discrete heads ( FIG. 7 ), in other implementations, a single stem has one head, two heads, three heads, four heads or more than six heads, e.g. 10 discrete heads.  
      While implementations have been shown in which hooks have lateral sides that are substantially parallel, in the implementation shown in  FIG. 8 , the lateral sides are not parallel.  
      While implementations have been shown in which indicia-forming features extend inwardly from a surface, in some implementations, they extend outwardly from a surface, providing indicia I in the form of cavities or recesses which extend inwardly from a surface of a fastener. Such outwardly extending indicia-forming features can, e.g., be made by electroforming.  
      While implementations have been shown in which fastener components are molded, in some implementations, the fastener components are formed by other processes. For example, fasteners can be made by profile extruding hook-shaped rails; cutting or severing the hook-shaped rails to form discrete elements; stretching the cut rails to increase separation between the discrete elements. In such instances, indicia can be formed by marking the resulting material, e.g., by scoring.  
      While implementations have been shown in which the indicia are molded, in some implementations, the indicia are formed by marking on a surface of the formed touch fastener. For example, the indicia can be formed by using a laser to melt or ablate material to form the indicia, or by using a printer, e.g., an inkjet printer to form the indicia. A suitable inkjet printer is the Spectra Nova-AAA printing module having 256 independently addressable jets that is capable of operation of up to 600 dpi is available from Spectra, Inc., Hanover, N.H. Laser marking systems are available from Universal Laser Systems, Inc., Scottsdale, Ariz. (USA), and Epilog Laser, Golden, Colo. (USA).  
      Accordingly, other embodiments are within the scope of the following claims.