JPH03121176A - Method for forming hot-melt self-adhesive - Google Patents

Abstract

PURPOSE:To form a hot-melt self-adhesive into small cut pieces free from blocking by allowing a high-temperature liquid hot-melt self-adhesive to flow through a discharge hole into a cooling water containing an anti-blocking agent and cutting it in a state in which the outside is solidified so that the cut faces come into contact with the cooling water. CONSTITUTION:A method for forming a hot-melt self-adhesive having a softening point higher than room temperature and tacky at room temperature (a thermoplastic material that becomes liquid usually at 50-200 deg.C or its mixture) into cut pieces, wherein the material liquefied at sufficiently high temperature is allowed to flow through a discharge hole into a cooling water containing an anti-blocking agent comprising a dispersion, emulsion or aqueous solution of a thermoplastic organic polymer and is cut in a state in which at least the outside is solidified so that the cut faces come into contact with the cooling water. By a surface coating with the anti-blocking agent, the small shaped product of the adhesive thus obtained is prevented from blocking to each other and sticking to the inside of a packaging container and bag. Since it is manufactured in one continuous process, the productivity can be remarkably improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for forming a hot melt adhesive into small, non-blocking pieces.

[Prior Art] Conventionally, it has been necessary to produce small pieces of a hot-melt adhesive that is sticky at room temperature and to finally pack them into containers, for example, containers in which the liquid material is released from the mold at a high temperature. Then, the whole container is sent to a cooling device to be cooled and solidified, and then taken out of the container again, or further cut there and then subjected to final packing with female pattern paper, release film, etc. Or put it in the designated release paper box and leave it to cool.

The method used was to continue packing.

[Point U while the invention is trying to solve the problem] The conventional method is not only time-consuming and low in productivity, but also has a practical limit to miniaturization, and it is difficult to store and store molded products together.
There was a problem in that blocking was likely to occur during transportation.

In addition, the person using the product must take each item out of the release box one by one or tear off the items wrapped in release paper, and must also dispose of the release paper or release box. However, there was a problem in that it was time-consuming.

Furthermore, disposing of the mold release box or the female pattern paper as industrial waste is an issue that must be resolved as soon as possible from the standpoint of environmental pollution and resource and cost savings.

The purpose of this invention is to solve the above-mentioned problems in the conventional technology when molding small-shaped hot-melt adhesive products, increase productivity through a single continuous process, suppress blocking of molded products, and reduce handling. It's about making it easier. Furthermore, it aims to save resources and protect the environment by eliminating the use of release paper and release boxes that were traditionally used in packaging.

[Means for solving the problem] In order to solve the above-mentioned problem when molding a hot melt adhesive having a softening point higher than that of chamber 1 and having tackiness at room temperature, it is made into a liquid state at a high temperature.

The cut surface flows into cooling water containing an anti-adhesive agent consisting of a thermoplastic organic polymer dispersion, emulsion, or aqueous solution, and the cut surface comes into contact with the cooling water containing the above-mentioned anti-adhesive agent with at least the outer surface solidified. It is characterized by being cut in such a way as to Now, the hot melt adhesive mentioned here refers to a thermoplastic substance or a mixture thereof that becomes liquid at a temperature of usually 50 to 200°C.

The present invention is a method for molding a hot melt adhesive into a small shape in a single continuous process, which makes it easy to standardize the shape and performance, saves 9 labors, and enables continuous mass production. Undesirable blocking between products or containers can be significantly suppressed.

The anti-adhesion agent used in the present invention is an organic polymer-based dispersion, emulsion, or aqueous solution.

Dry solids refer to polymeric substances that melt when heated but are not sticky at room temperature.By using these as a cooling medium and a contact medium during cutting, the surface of a hot melt adhesive that is sticky at room temperature is This objective is achieved by coating the material in the form of a thin film or fine powder.

Anti-adhesion agents include thermoplastic elastomers, low-density polyethylene, ionomers, ethylene-vinyl acetate copolymers,
Aqueous dispersions, emulsions, aqueous solutions, etc. using polyethylene wax, polyethylene glycol, or modified products thereof as the main raw materials for the dispersion resin are used.

The solid content concentration of the anti-adhesion agent in the cooling water and the contact medium during cutting is 1.0% or more and up to 40%. It adheres to molded products and is consumed, so it must be constantly replenished. If it is less than 1.0%, the adhesion prevention effect of the hot melt adhesive is insufficient, and if it exceeds 40%, the amount of adhesion to the hot melt adhesive is too large and may change the performance and physical properties of the hot melt adhesive. Not only does it occur, but it is also accompanied by the drying process, making it uneconomical. The solid content concentration is usually preferably 3 to 20%.

As for the type of anti-adhesion agent, water-based dispersions such as low-density polyethylene and polyethylene wax are relatively preferable from the viewpoint of anti-adhesion effect and handling properties, although it depends on the type of the sticky solid.

The temperature of the cooling water containing the anti-adhesive agent may be such that the molten substance is once cooled and solidified into a rod-shaped solid and does not fuse before breaking, and it is sufficient that it is 40 degrees Celsius or below at a temperature that does not freeze. , substantially preferably 2 to 20°C.

Cutting is not particularly limited as long as it is a cutter that can cut continuously, such as a bi-rotary blade, but cutting is done in cooling water with anti-stick agent dispersed or dissolved in it, or cooling water with anti-stick agent dispersed or dissolved in the blade and It is necessary that the cut surface be coated with powder or sprayed with powder.

[Function] The present invention involves a manual process in which a hot melt adhesive is flowed down from a discharge port into cooling water containing an anti-adhesive agent at a high temperature higher than its softening point, and then a cut surface is poured into the cooling water containing an anti-adhesive agent. Step B consists of cutting the pieces so that they are in contact with each other.

In step A, the hot melt adhesive is cooled to solidify at least the outer surface, and at the same time, the anti-adhesive agent is attached to the outer surface and coated in the form of a thin film or fine powder.

In process B, the rod-shaped solid whose at least the outer surface has solidified and is no longer blocking in process A is cut in cooling water in which an anti-adhesive agent is dispersed or dissolved, or in cooling water or powder mist in which an anti-adhesive agent is dispersed or dissolved. Ru. Therefore,
This hot melt adhesive has a small shape that is convenient to handle, such as a cylindrical shape or a modification thereof that does not block the entire surface.

[Examples and Comparative Examples] The present invention will be described below with reference to two examples, but the present invention is not limited to these examples.

Example 1 A hot melt adhesive consisting of styrene block copolymer (SIS), Tazuki Fire, and naphthenic oil was kneaded and manufactured, and then passed through an extruder for 14 hours.
From the discharge port at 0°C, 5 to 50% of polyolefin dispersion aqueous liquid (manufactured by Sikata Kagaku Kogyo ■, Chemipearl S-100) containing 10%
It was extruded into a rod shape into cooling water at 10°C. When the surface of the adhesive reached 20° C. while flowing through a cooling water channel, it was continuously cut with a rotating blade in cooling water. The shape is approximately φ20
m m.

Drain continuously to a length of 30 to 40 mm. The product was dried in a continuous hot air dryer.

The molded sticky solid has a non-stick surface at room temperature;
Put 20kg in a polyethylene bag and store at 40°C in a cardboard box.
There was no blocking even after holding at 5 for 48 hours.

In addition, the amount of attached polyolefin is based on the adhesive,
It was 0.20% and did not affect the performance of the melted adhesive.

In other words, the softening point of the one with 0% polyolefin adhesion is 83.
'C, melt viscosity 6,350 cp/170°C, pole tack 21. Adhesive strength 850g/25mm,
Softening point of 0.20% polyolefin adhesion 83
°C9 melt viscosity 6. 400ep/170℃, pole tack 21. Adhesive strength 860 g / 25 mm Comparative Example 1-1 The same hot melt adhesive as in Example 1 was similarly extruded into a rod shape at 140° C. into water at 5 to 10° C. from the discharge port. When the surface reached 20° C. while flowing through a cooling channel, it was cut into pieces using a rotating blade under water and dried.

When cutting, it easily stuck to the blade during one turn and could not be cut continuously.

Moreover, the molded products stuck to each other and to the inner wall of the container at room temperature, making it difficult to handle them.

Comparative Example 1-2 The same hot melt adhesive as in Example 1 was poured at 140° C. from the discharge port into a volumetric 101 iron vat whose inner surface was coated with a release agent. After about 10 hours of cooling, I wanted to cut the wheat into 1/8 pieces using a guillotine cutter.It was impossible to cut the wheat with a guillotine after 8 hours because it had not completely cooled and was still flexible and highly sticky.)0 Because the surface tack was large. Each piece was wrapped in release paper and 20Kg was packed in a cardboard box.

Thus, manufacturing and packaging required a long time, troublesome labor (including dangerous work), and extra packaging materials.

Example 2 Styrene block copolymer (SIS+5BS).

A tackifier produces a hot-melt adhesive made of naphthenic oil by kneading it in a kneader, and passes it through an extruder.
Polyolefin aqueous dispersion (manufactured by Mitsui Petrochemical Industries ■) was carried out at 40°C from the discharge port.

It was extruded into a rod shape into a cold water bath at 10 to 15°C containing 15% Chemivar W-400).

While flowing in a cooling water tank, when the surface of the adhesive reached 25°C, it was pulled out of the cage and cut with a rotating blade while spraying cooling water at 10 to 15°C containing 20% of the above polyolefin aqueous dispersion. .

The shape is approximately 20 mm in diameter and 30 to 35 mm in length.

The product was made by continuous draining and drying in a continuous hot air dryer.

The molded sticky solid is not sticky at room temperature.

Put 20kg in a polyethylene bag and store at 40℃ in a cardboard box.
There was no blocking even after holding for 48 hours.

In addition, the amount of attached polyolefin is 0 to the adhesive.
．． 22% and had no effect on the performance of the molten adhesive.

In other words, the softening point of the polyolefin with 0% adhesion 9
6°C9 Melt viscosity 3,600cp/170°C Ball tack 3. Adhesive strength 1,900g/25mm,
Softening point of 0.22% polyolefin coating: 97°C, melt viscosity: 3.600 cp/17
0℃, ball tack 3. Adhesive strength 1, 930g/25
mm Comparative Example 2-1 The same hot melt adhesive as in Example 2 was heated at 140°C in the same manner.
It was extruded into a rod shape from the discharge port into water at 10 to 15°C. While flowing in a cooling water tank, when the surface of the adhesive reached 25°C, it was removed from the tank and cut with a rotary blade while spraying water at 10 to 15°C.

When cutting, it easily stuck to the blade during one turn and could not be cut continuously.

Moreover, the molded products stuck to each other and to the inner wall of the container at room temperature, making it difficult to handle them.

Comparative Example 2-2 The same hot melt adhesive as in Example 2 was poured from the discharge port at 140°C into a polypropylene tray with a capacity of 1 mm, which had been treated with an inner surface R. ).

Let it cool for about 3 hours, but after 2 hours it was difficult to make sushi.) Wrap each piece in a patterned paper.

Packed in a 20kg cardboard box.

From manufacturing to packaging, it takes a long time and a lot of trouble (filling into trays, moving).

A place was needed to cool it down. In addition, a cover was required to prevent foreign substances such as dust and insects from entering the air.

Example 3 Styrene block copolymer (S B S ), ethylene-vinyl acetate copolymer tackifier A hot-melt adhesive consisting of naphthenic oil was kneaded, passed through an extruder, and heated from the discharge port at 135 to 140°C. Polyethylene oxide (manufactured by Sanyo Chemical Industries, P
EG-40008) 20% water soluble iα at 10-15℃
It was extruded into a rod shape into a cooling water bath.

When the surface of the adhesive reaches 30°C, it is taken out of the cooling water tank, and 1 part of the above 20% polyethylene oxide aqueous solution is added.
The adhesive was heated to 0°C and cut using a 9-rotary blade while applying pressure to the cut surface of the adhesive and the rotary blade.

The shape was approximately 30 mm in diameter and approximately 30 mm in length, and a product was obtained by continuous draining and drying in a hot air dryer.

The molded solid is non-tacky at room temperature and remains stable even when placed in a polyethylene laminate bag and kept at 40°C for 48 hours.
There was no blocking.

Note that the amount of polyethylene oxide attached to the surface is
It is 0.19% of the adhesive, and the performance of the adhesive is:
It had no impact.

In other words, the amount of polyethylene oxide deposited is 0%.
Softening point: 95℃, melt viscosity: 4,600Cp/170
℃ Ball Tadzuku 3. Adhesive strength 1゜500g/25m
m, Softening point of 0.19% polyethylene oxide coating: 95°C, Melt viscosity: 4. 600cp
/170°C, pole tack 3. Adhesive strength 1. 55
0g/25mm Comparative Example 3-1 The same hot melt adhesive as in Example 3 was used, but the pond was carried out under exactly the same conditions as in Example 3, except that the polyethylene oxide aqueous solution was not used in the cooling tank or in the pressure application during cutting.

When cutting, it easily stuck to the 9-turn blade and could not be cut continuously. It was also molded. The molded products stuck to each other and to the inner surface of the packaging bag at room temperature, making it difficult to handle.

Comparative Example 3-2 The same hot melt adhesive as in Example 3 was used with 135 to 14
I poured it from the outlet at 0°C into a box made of release paper, and it stopped flowing even if I tilted it.

It took about 2 hours with the lid open. This thing is.

It was difficult to stack them on top of each other, so I packed them side by side.

In this way, it takes a long time and troublesome work (filling into trays, moving) to manufacture and package.

A place was needed to cool it down. In addition, a cover was required to prevent foreign substances such as dust and insects from entering the air. Also, this peeling box is 1! Throw it away.

Since it could not be recovered, the expenses were wasted. The user had no choice but to dispose of it, which took time and effort, and became a cause of environmental pollution.

[Effects of the Invention] The small-sized hot melt adhesive products obtained by the present invention have a surface coating with an anti-adhesive agent, which prevents blocking between small-sized hot melt adhesive products and the inner surface of packaging containers and packaging bags. The adhesion of hot melt adhesives is suppressed, and all handling, including storage and transportation, until the user reheats and melts the hot melt adhesive becomes easier.

Furthermore, in the method of the present invention, the production is performed in a single continuous process, so productivity is significantly improved.

Furthermore, there is no need for a female box or a release paper, which were conventionally required, and it can be handled in the same way as non-adhesive solid small-shaped products.

Claims (1)

[Claims] In a method of molding a hot melt adhesive that has a softening point higher than room temperature and is sticky at room temperature into individual pieces, the above-mentioned substance, which becomes liquid at a sufficiently high temperature, is poured into a thermoplastic organic material from a discharge port. Polymer-based dispersion
It flows into cooling water containing an anti-adhesive agent consisting of either an emulsion or an aqueous solution, and in a state where at least the outer surface is solidified, the anti-adhesive agent consisting of an anti-adhesive agent consisting of a thermoplastic organic polymer dispersion, emulsion, or aqueous solution is cooled. A method for molding a hot melt adhesive, characterized by cutting the adhesive so that the cut surface comes into contact with cooling water.