JPS6119679A - Adhesive for foot wear component - Google Patents

Abstract

PURPOSE:To provide the titled adhesive which allows to carry out heat-sensitive bonding at a low temp. and does not cause blocking, consisting of a polyurethane contg. crystalline high-molecular segment obtd. from a crystalline high- molecular compd. and an aliph. or arom. polyisocyanate. CONSTITUTION:A crystalline high-molecular compd. such as a polycaprolactone polyol obtd. by addition-polymerizing epsilon-caprolactone in the presence of an initiator such as ethylene glycol, is reacted with an aliph. or arom. polyisocyanate to obtain a polyurethane having a crystalline high-molecular segment content of 65-98wt%. The titled adhesive composed of said polyurethane can be bonded at a low temp. (80-100 deg.C) and is a heat-sensitive adhesive which does not cause blocking without the insertion of any release paper.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a shoemaking adhesive that is applied to shoemaking parts as a pre-process of shoemaking work, and in particular, an adhesive that can be bonded at a relatively low temperature and dislikes high temperatures. This invention relates to an adhesive for shoe making parts that can be applied to shoe making parts and does not cause blocking.

[Description of the prior art and its problems] Conventionally, polyamide-based, polyester-based, EVA-based, vinegar-based adhesives, etc. have been generally used as heat-sensitive adhesives for shoe manufacturing parts. Among these heat-sensitive adhesives, those used in the hanging process (toe last, side last, heel seat last), etc. can also be used as relatively high-temperature adhesives, and there are few problems. When applied to parts such as cores (boxes and tows) and molds (counters), the amount of heat is so small that it would be unimaginable for heat-sensitive adhesives to work properly or functionally. In many cases, adhesives can only be applied at low temperatures and for short periods of time, and in these cases, low-temperature active or adhesive adhesives, which are polyester-based, EVA-based, vinyl acetate-based adhesives, etc., with a large amount of wax or caustic agent added are used. It is used.

However, the adhesive is not applied at the shoe manufacturing factory, but at the parts supplier's factory, and the adhesive is applied over a period of time (
After several days to several months), the shoes are transported to a shoe factory. For this reason, during this period (from application to use), the parts are stacked on top of each other, so if release paper is not inserted between them, they will block and become unusable as parts (especially, summer is dangerous).

These contradictory points, namely, low m (80-100℃)
There was a need for an adhesive that could be activated by the adhesive without any problems with adhesion, and that would not cause blocking without the use of release paper.

[Means for Solving the Problems] The present invention was completed with the aim of solving the above-mentioned contradictions and providing a shoemaking adhesive that can be activated and bonded at low temperatures and does not cause blocking. It is characterized by the use of a polyurethane-based heat-sensitive adhesive having crystalline polymer segments as a shoemaking adhesive.

The polyurethane used in the present invention contains a crystalline polymer compound as a segment, and specifically includes polycaprolactone polyol, polyester polyol, and polycarbonateol. Polycaprolactone polyol is obtained by addition polymerizing ε-caprolactone using an initiator such as ethylene brecol.
Examples of polyester polyols include polyester polyols of aliphatic and/or aromatic diols and aliphatic and/or aromatic dicarboxylic acids.

Specific examples of polyester polyols include polyester polyols of 1.6-hexanediol and adipic acid, and polyester polyols of 1,4-butanediol and terephthalic acid.

In addition, specific examples of polycarbonate polyols include:
Examples include those obtained by reacting 1,6-hexanediol and ethylene carbonate.

These polyols are reacted with an aliphatic or aromatic polyisocyanate to obtain polyphrethane, which is the shoe adhesive of the present invention. The content of the crystalline polymer segment in the polyurethane is 65-981% by weight, preferably 80-'9
It is 5% by weight.

Note that shoe-making with adhesive can be made by heating and melting the adhesive and applying it to shoe-making parts, or by applying a diluted solution of the adhesive dissolved in a solvent such as an organic solvent to shoe-making parts. You can get parts for.

[Example 1] The adhesive of the present invention was dissolved in various solvents and applied to shoe manufacturing parts such as molds and counters by electrostatic coating or a general coating method. As a result, taking the mold counter as an example, even if it is continuously stacked and left for a long period of time in an atmosphere at 50°C after coating, it will not block.
Even with heat pressing, which cannot be said to be good under certain conditions, good adhesion to natural leather, artificial leather, synthetic leather, various woven fabrics, non-woven fabrics, etc. could be obtained. In addition, no difference was observed among the application methods: dobuzuke method, brush coating method, and electrostatic coating method.

[Example 2] The adhesive according to the present invention was tested as a hot-melt adhesive in the form of solvent-free pellets, powder, thin film, rond, etc. 80℃~1 for sheets of styrene, rubber, and other thermoplastic resins, leather boards, fiberboards, etc., which are commonly known as materials for toecaps and molds.
The film was coated on both sides or one side at a temperature of 00°C to a film thickness of about 20 to 50 microns.

As a result, it was confirmed that it functions satisfactorily as a heat-sensitive adhesive, does not cause blocking during storage, and has no adverse effect on any of the materials.

[Effects of the Invention] The present invention relates to a polyurethane heat-sensitive adhesive having a crystalline polymer segment, which is used for shoe manufacturing parts. ImA shoe parts have the remarkable effect of being able to be heat-sensitively bonded to loose members at low temperatures using the above adhesive, and without causing blocking during storage.

Claims (1)

[Claims] A polyurethane heat-sensitive adhesive with crystalline polymer segments.