Process for joining polyurethane coated fabrics

• US 4,508,582 A
• Filed: 02/06/1984
• Issued: 04/02/1985
• Est. Priority Date: 02/06/1984
• Status: Expired due to Fees

• Current Assignee: Bata Schuh AG (International Footwear Investment BV)
• Original Assignee: Bata Schuh AG (International Footwear Investment BV)
• Inventors: Fink, Hans
• Primary Examiner(s): Dawson, Robert
• Application Number:
  US06/577,024
• Time in Patent Office: 421 Days
• Field of Search: 12/142 A, 12/142 C, 12/142 D, 12/146 CK, 36/16, 36/17 A, 36/17 PW, 36/17 R, 36/19 A, 36/21, 36/45, 36/47, 36/87, 156/93, 156/222, 156/227, 156/304.4, 156/292, 156/308.4, 156/275.1, 428/104
• US Class Current: 156/93
• CPC Class Codes: A43B 7/12 Special watertight footwear overshoes A43B3/16
• CPC Class Codes: B29C 53/36 Bending and joining, e.g. for making hollow articles B29C53/56 takes precedence
• CPC Class Codes: B29C 65/72 by combined operations or combined techniques, e.g. welding and stitching
• CPC Class Codes: B29C 66/112 Single lapped joints
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/135 Single hemmed joints, i.e. one of the parts to be joined being hemmed in the joint area
• CPC Class Codes: B29C 66/43 Joining a relatively small portion of the surface of said articles B29C66/45 takes precedence
• CPC Class Codes: B29C 66/431 Joining the articles to themselves B29C66/4322 and B29C66/4332 take precedence
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/723 being multi-layered B29C66/7292, B29C66/72941 take precedence
• CPC Class Codes: B29C 66/7292 coated B29C66/72941 takes precedence
• CPC Class Codes: B29K 2075/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: Y10T 156/1051 by folding
• CPC Class Codes: Y10T 428/2405 Coating, impregnation, or bond in stitching zone only

Abstract

A process for forming a strong, pressure-tight joint between fabric substrates includes coating each substrate with polyurethane on one side, superimposing the fabric substrates so that the polyurethane layers are together, welding elongated regions of the polyurethane together under heat and pressure and sewing through the weld. The edge is then folded over and bonded to itself and the material is spread out. The resulting material can be bonded to a sole to form a waterproof, lightweight boot.

Claims

1. A process for forming a pressure-tight and tension-proof joint between fabric substrate comprising the steps of

coating one side of each substrate with a layer of polyurethane,

placing the substrates adjacent each other with the polyurethane layers together,

applying pressure to a selected region near an edge of the adjacent fabric substrates and inductively heating the selected region so that the polyurethane material in the selected region is welded together,

sewing a seam along the region so that the stitching passes through the weld thus formed,

folding over and adhering the material of the welded substrates along the welded region so that a portion of one of the substrates along the selected edge lies against and is bonded to itself, and

separating and spreading out the remainder of the coated fabric substrates.

2. A method of forming a shoe including forming an upper in accordance with Claim 1 and bonding the upper to a sole, the subsequent processing including the upper being accomplished in the absence of solvents and elevated temperatures.