JP2001049226A - Hot-melt adhesive and hot-melt adhesive tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hot-melt adhesive excellent in workability in bonding, easily applicable even to the surface of an irregular-shaped adherend, and capable of being used in the state filled into a tube for further convenience, which adhesive comprises a hot-melt powder, a highly water-absorbing polymer, and water and has flowability. SOLUTION: A hot-melt adhesive that can be easily handled because of its flowability is obtained by mixing 50-70 wt.% hot-melt powder with 0.3-1 wt.% highly water-absorbing polymer and 35-45 wt.% water. The hot-melt powder is not limited to a thermoplastic resin but may be a powder of a thermoplastic resin such as an ethylene/vinyl acetate copolymer, a polyamide, a polyester, a polyurethane, an ethylene/ethyl acrylate copolymer, an atactic polypropylene, or a polyethylene. The hot-melt adhesive can be used in the state filled into a tube because it has flowability corresponding to a desired viscosity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hot melt adhesive and a tube filled with the adhesive.

[0002]

2. Description of the Related Art Conventionally, there has been known a hot-melt adhesive of a type which is softened or melted by heating, applied to an adherend, pressed, and then rapidly fixed by cooling. This hot melt adhesive has an ethylene-vinyl acetate copolymer (EV
A), polyamide (PA), polyester, polyurethane, ethylene-ethyl acrylate copolymer (EEA),
Atactic polypropylene, polyethylene and the like are used. In addition, the adhesive has a base polymer as a main component, a tackifier, a wax, an antioxidant, a filler, a compound in which a plasticizer and the like are blended to impart adhesiveness and coating properties, and polyester and polyamides. Some base polymers can be used as hot melts alone, and are usually commercially available in the form of films, rods, strings, lumps, powders, webs, and pellets.

[0003] As a conventional hot melt adhesive bonding method, a film, a web, a powdery adhesive or the like is applied to an adherend in advance, or is placed between adherends and integrally heated with the adherend. There is a method of bonding.

As described above, the hot melt bonding system is excellent in workability, not only contributes to labor saving and energy saving, but also excellent in safety and pollution-free.

[0005]

However, the above-mentioned conventional hot-melt adhesive is coated in advance on a film, a web (tape), or a cloth such as an emblem. In this case, it is difficult to apply a tape-like hot melt, and it is also difficult to apply a hot melt powder in advance.

Accordingly, the present invention provides a hot melt adhesive which can be easily applied to the surface of a deformed adherend, and a hot melt adhesive tube which can be easily applied by ordinary users. Aim.

[0007]

Means for Solving the Problems In order to achieve the above object, the present invention takes the following technical means.

That is, the hot melt adhesive of the present invention is obtained by dispersing a hot melt powder in a liquid having a predetermined viscosity. According to the present invention, it is possible to impart fluidity with a desired viscosity, so that it can be handled in the same manner as a general adhesive, and can easily perform a coating operation on a deformed adherend. In addition to this, it is possible to fill the tube and use it, and the coating workability is further improved. The hot melt powder is not limited to a specific thermoplastic resin, but may be ethylene-vinyl acetate copolymer (EVA), polyamide (PA), polyester, polyurethane, ethylene-ethyl acrylate copolymer (EE).
A), it is possible to use various thermoplastic resin powders such as atactic polypropylene and polyethylene,
It is also possible to mix and use a plurality of these.

As the liquid having a predetermined viscosity, various liquids can be used, but those having little adverse effect on the physical properties and quantity with respect to the hot melt powder are preferable. As such a liquid, for example, a liquid obtained by absorbing water of several tens to several hundreds times its own weight into a powder or granules of a superabsorbent polymer can be used. According to this, a very small amount of the superabsorbent polymer with respect to the hot melt powder and the physically stable water form a jelly-like liquid, and the hot melt powder is mixed and dispersed in this liquid. Is possible.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described.

The hot melt adhesive of the present invention contains a hot melt powder, a superabsorbent polymer and water, and can have fluidity. That is, by mixing and dispersing the hot-melt powder with the superabsorbent polymer which has been converted into a jelly-like liquid by absorbing water, a hot-melt adhesive having a predetermined viscosity and fluidity can be obtained.

The content of the hot melt powder can be determined as appropriate, but is preferably from 50% by weight to 70% by weight, more preferably from 55% by weight to 6% by weight.
It can be 5% by weight or less.

The content of water can be variously determined according to the required viscosity, but can be 50 times or more the weight of the superabsorbent polymer and not more than the upper limit of the water absorption of the superabsorbent polymer. The content of water with respect to the total weight of the adhesive is preferably 35% by weight or more and 45% by weight or less. Further, the content of the superabsorbent polymer is preferably from 0.3% by weight to 1% by weight.

The superabsorbent polymer can be used in the form of powder or granules. Examples of this superabsorbent polymer include sodium polyacrylate crosslinked product, starch-acrylonitrile graft copolymer, starch-acrylic acid graft copolymer, starch-acrylamide graft copolymer, cellulose-acrylonitrile graft copolymer, carboxymethyl cellulose. Appropriate materials such as cross-linked products, hyaluronic acid, polyvinyl alcohol cross-linked products, polyvinyl alcohol water-absorbing gel frozen / thawed elastomers, sodium acrylate-vinyl alcohol copolymer, sodium polyacrylate cross-linked products, and N-substituted acrylamide cross-linked products it can.

The hot-melt adhesive described above has fluidity with a desired viscosity and can be used by filling the inside of the tube.

[0016]

EXAMPLES Examples of the composition of the hot melt adhesive of the present invention are shown below. [Formulation Example] EVA powder 60% by weight Water 39.5% by weight Crosslinked sodium polyacrylate powder 0.5% by weight

The hot melt adhesive of the above formulation was filled in a tube and used as an adhesive for raising the hem of pants. That is, when the hot melt adhesive was applied to the trouser hem using such a tube, the workability was very good, and the adhesive could be applied in an appropriate amount without soiling the hands. Then, when heated using an iron, the water contained in the sodium polyacrylate of the adhesive was evaporated, and the hot melt powder was melted, and the trouser hem was adhered neatly.

After the adhesion, the amount of the crosslinked sodium polyacrylate compounded for imparting fluidity is extremely small as compared with the hot melt, so that there is no problem in daily life.

[0019]

According to the hot melt adhesive of the present invention,
Since fluidity with a predetermined viscosity is provided, it is excellent in adhesive workability, can be easily and quickly applied to deformed adherends, and can also be used by being housed in a tube. Further convenience and preservability can be improved.

Further, according to the hot-melt adhesive provided with fluidity by dispersing the hot-melt powder in a superabsorbent polymer that absorbs water several tens times its own weight, the physical properties and the amount of No adverse effects and excellent long-term storage properties can be obtained.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E014 KA02 3E065 GA03 4J040 DA021 DA051 DA061 DA101 DE031 DF012 DF041 ED001 EF001 EG001 HA126 JA03 JA07 JB01 PA43

Claims (7)

[Claims] 1. A hot melt adhesive comprising a hot melt powder dispersed in a liquid having a predetermined viscosity. 2. A hot melt adhesive comprising a hot melt powder, a superabsorbent polymer and water and having fluidity. 3. The hot melt adhesive according to claim 2, wherein the content of the hot melt powder is 50% by weight or more and 70% by weight or less. 4. The hot melt adhesive according to claim 2, wherein the water content is at least 50 times the weight of the superabsorbent polymer and not more than the upper limit of the water absorption of the superabsorbent polymer. 5. The water content is not less than 35% by weight and not less than 45% by weight.
Less than 0.3% by weight of the superabsorbent polymer
The hot melt adhesive according to claim 4, which is not less than 1% by weight. 6. The hot melt adhesive according to claim 2, wherein the superabsorbent polymer is a crosslinked sodium polyacrylate. 7. A hot melt adhesive tube filled with the hot melt adhesive according to any one of claims 1 to 6.