US2095209A

US2095209A - Method of making slide fasteners

Info

Publication number: US2095209A
Application number: US681529A
Authority: US
Inventors: Henry W Brownsdon
Original assignee: Hookless Fastener Co
Current assignee: Hookless Fastener Co
Priority date: 1932-10-15
Filing date: 1933-07-21
Publication date: 1937-10-05
Anticipated expiration: 1954-10-05

Description

Oct. 5, 1937.. H. w. BROWNSDON METHOD OF MAKING SLIDE FASTENERS Original Filed Oct. 15, 1932 .m. mm mm w W m By W 5% A TTORNEYS.

Patented Oct. 1 937 assignor to Hookless Fastener Company, a corporation of Pennsylvania Original application October 15, 1932, Serial No. 637,984, now Patent No. 1,920,138, dated July 25, 1933. Divided and thisapplicatlon July 21, 1933, Serial No. 681,529.v In Great Britain October 17, 1931 a This invention relates to separable interlocking fasteners in which two rows of fastener members are attached to a pair of tapes and so constructed that the elements of one row interlock with those 5 of the other row. The fastener members may assume various forms, the form used in illustrating-this invention being that of a well known slide fastener in which the two rows of fastener elements are interlocking and separated by a slider. Y

This application is a division of the application, Ser. No. 637,984, filed October 15, 1932, jointly with George H. C. Corner, now Patent No. 1,920,138.

It is among the objects of this invention to provide a strong and improved bond between non-metallic fastener members and their supporting strips or tapes. More specifically it is one of my objects to provide a fastener in which 20 there is an integral bond between the fastener members and the supporting strips or tapes.

One of the features of the invention consists in forming an intimate joint between each individual interlocking element and a supporting 5 strip, for example, a homogeneous, autogenous,

' or physico-chemical bond between the interlocking element and material constituting or included in the strip.

Other objects and advantages of the invention 30 will be apparent from the accompanying description and drawing, in which: I

Fig. 1 is aperspective viewof a complete fastener stringer embodying the invention, Fig. 2 is a cross-section'of a tape at one stage 35 of the manufacture of a fastener in accordance with one embodiment of my invention, the proportions of some elements being exaggerated for clearness, and a Fig. 3 is an enlarged perspective view of a tape after being prepared, as indicated in Fig. 2, for the attachment of the interlocking elements.

' In Fig.v 1, Iii represents a flexible supporting.

' member, preferably in-the formof a fabric .tape, to the edge of which'are secured in uniformly 45 spaced relation a number of interlocking elements, exemplified as including an interlocking h'ead'portion l2 projecting from the edge of the tape and a supporting base portionbifurcated to provide two legs it which straddle the tape '50 and are secured to it.

In accordance with the present invention the interlocking elements are formed of nonmetallic material, examples of which are cellulose ester or ether materials, such a pyroxylln or nitro-cellu- 55 lose; synthetic resins, such as resinous polymerized unsaturated organic compounds, phenolaldehyde resins, ureaor thiourea-aldehyde resins, polyhydric-alcohol-polybasic acid resins; and compressed and/or impregnated fiber.

,For the sake of illustration, we may consider that the interlocking elements are formed of cellulose benzyl ether molding powder. A thin strip of plasticized cellulose benzyl ether which has been softened by heat or by soaking in a solvent, is applied to one or both faces of a fabric strip along one edge. In Fig. 2 the fabric strip I0 is placed between the bonding strips I6 of softened cellulose benzyl ether and pressed between two rollers l8. This operation rolls the strips it into the interstices of the fabric and forms an intimate attachmentbetween the two, resulting in a perfectly flexible fabric base impregnated with the cellulose benzyl ether to form an adhesive or bonding edge, as shown in Fig. 3. The completely formed interlocking elements in this instance made of cellulose benzyl ether, are then placed along the tape as shown in Fig. 1, in the desired closely and uniformly spaced relation and attached to the tape. Conveniently the interlocking elements may be applied while the strips l8 are still soft from the rolling operation butpreferably the strips l6 and the jaws Mare softened for this step in the process. When the solvent evaporates, the stickiness of the material disappears and the interlocking elements are integrally united to the strips it which previously have been pressed into the interstices of the fabric tape. The supporting tape thus contains an intimately and firmly attached root or support,

intermingled with the flbers of the fabric, which support has become integral with the material of the interlocking elements. Likewise the interlocking elements are homogeneously united to the bearing elements it. However, the strips it do not impair the flexibility of the tape. 7

The term bonding material as used herein and in the appended claims means a material in the plastics class which under ordinary conditions of temperature and pressure is hard and which is capable of being softened by the action of heat or solvent. The term impregnated: as used in conjunction with bonding material" means forced into the interstices of the fabric or equivalent porous support by the action of pressure while the material is in a soft or semi-soft condition and is intended to distinguish from the mere common application of liquid or semi-liquid cement.

The interlocking elements may also be applied first and softened after application. This softening may be accomplished by heat, or the tape may be saturated either with a suitable solvent alone, or with a solution of the material of which the elements are formed. This acts to soften the inner faces of the applied prongs.

While I have shown and described in this application one embodiment which my invention may assume in practice, it will be understood that this embodiment is merely for the purpose of illustration and description and that various other forms may be devised within the scope of my invention as defined in the following claims.

What I claim as my invention is:

l. The method of making separable interlocking fasteners of the type having fastener elements uniformly spaced along the edge of a fabric support, which consists in applying bonding material continuously along the supporting edge under sufllcient presure to cause said material to impregnate the fabric, arranging a series of fastener elements at uniformly spaced intervals on said bonding material, and uniting the same thereto by temporarily softening the material of the contacting surfaces suillciently to cause them to adhere together.

2. The method of making separable interlocking fasteners of the type having fastener elements secured to a fabric support at uniformly spaced intervals, which consists in applying thin strips of bonding material to the supporting edge while in a semi-plastic condition and with sufficient pressure to cause said bonding material to impregnate the fabric, said bonding material being soluble, and arranging fastener elements made of a material soluble in the same solvent as said bonding strips at uniformly spaced intervals along the supporting edge, and thereafter softening the surfaces of said bonding material and a fastener elements by solvent sufficiently to cause them to adhere together.