KR100278404B1 - Manufacturing method of double sided adhesive tape - Google Patents

Abstract

The present invention provides a double-sided pressure-sensitive adhesive tape in which the foamed base material layer and the pressure-sensitive adhesive layer are integrally formed by simultaneously forming the base material and the double-sided pressure-sensitive adhesive layer without using a foam sheet manufactured separately from a conventional tape base material, and then foaming the base material layer. It is about a method.

By forming the foam base layer and the pressure-sensitive adhesive layer integrally, the thickness of the foam base layer can be arbitrarily adjusted up to about 100㎛ without layer separation or peeling phenomenon, and the thickness is 100 ~ 500㎛ that exceeds the limit of the thickness of the conventional foam sheet. The present invention relates to a method of manufacturing double-sided adhesive tape that can make extremely thin products.

Description

Manufacturing method of double sided adhesive tape

TECHNICAL FIELD This invention relates to the manufacturing method of the double-sided adhesive tape which uses a film form or sheet form elastic body as a base material of a tape.

In the industrial tape, a double-sided adhesive tape formed by using a film- or sheet-like elastic body as a base material and a pressure-sensitive adhesive layer formed on both sides of the base material adheres relatively light objects to a wall, or is specific to automobiles, machinery, and home appliances. It is used for the purpose of making both sides stick together simultaneously like attaching a mark.

Conventionally, such a tape manufacturing method is based on a foamed film having a thickness of 1 to 1.5 mm made by foaming a synthetic resin or rubber-based elastic film or a foamed sheet obtained by thinly skiving an elastic body foamed into a bulk. Extruded film or sheet into which the foaming agent is incorporated into the polymer elasticity, and put it on the release paper and foamed, then apply the pressure-sensitive adhesive on both sides of the film or sheet to form a pressure-sensitive adhesive layer and laminated the release paper on the pressure-sensitive adhesive layer The double-sided adhesive tape as shown in FIG. 1 (A), (B) has been manufactured.

Elastic materials for tape production include polyethylene, polyvinylchloride (PVC), polyurethane (polyurethane), and rubber (including natural rubber, synthetic rubber, and mixtures of natural and synthetic rubber). The foam sheet of the elastic body is made to be in a state that the cell (Cell) is exposed on the surface.

When the above material is used as a tape substrate and an adhesive (acrylic adhesive or rubber-based adhesive) is applied to both sides of the tape substrate, the adhesive force between the substrate and the adhesive is always a problem. Since the adhesive layer and the substrate are easily separated from the adhesive surface, or the foamed sheet is PVC, the plasticizer is eluted (this is called bleeding phenomenon). In order to improve adhesion of the adhesive layer to the surface of the substrate, it is inconvenient to perform corona discharge, sputtering, or primer treatment using chemicals on the surface of the substrate. This increases the cost of production.

The present invention is to form a base and a double-sided pressure-sensitive adhesive layer at the same time without using a foam sheet prepared separately from a conventional tape base material to foam the base layer so that the foam base material and the pressure-sensitive adhesive layer is integrated.

By forming the foam base material and the pressure-sensitive adhesive layer integrally, the thickness of the foam base material layer can be arbitrarily adjusted to about 100㎛ (0.1mm) without layer separation or peeling phenomenon, and the thickness beyond the limit of the thickness of the conventional foam sheet There is an advantage to make an extremely thin product of 100 ~ 500㎛.

1 is a manufacturing process of the double-sided adhesive tape according to the present invention.

2 is a cross-sectional view of a known double-sided adhesive tape,

(a) shows the state that the release paper is adhered to both sides,

(b) shows a state in which release paper is adhered to one side name.

* Description of the symbols for the main parts of the drawings *

1: Tape base material 1a: Polymer elastic film

2. 2 ': pressure sensitive adhesive 2a, 2a': pressure sensitive adhesive layer

3,3 ', 3 ": release paper

The pressure sensitive adhesive used in the present invention may be a known acrylic pressure sensitive adhesive or rubber pressure sensitive adhesive well known in the art. Method for forming a foam base layer in the present invention is as follows.

The present invention is characterized in that a thermally expandable microcapsule-type blowing agent is used as a blowing agent, and the usable elastomer resin is compatible with an aromatic solvent such as toluene or an acetate-based solvent such as ethyl acetate, and naphtha. As an elastomeric resin having aging properties, acrylic copolymer resin, nitrile rubber (hereinafter referred to as NR) chloroprene rubber (hereinafter referred to as CR) and acrylonitrile rubber (hereinafter referred to as AN) ) Styrene-butadiene-Rubber (hereinafter referred to as SBR) Styrene-isoprene-Styrene Rubber (hereinafter referred to as SIS) Styrene-butadene-styrene Rubber (hereinafter referred to as SBS) Ethylene vinyl acetate copolymer, ethylene acrylate copolymer, copolymerization of vinyl chloride and vinyl isobutyl ether Would, either polyurethane, cellulose acetate, such as solvent-soluble resin surface in agarose can be used.

The thermally expandable microcapsules forming the foam layer used in the present invention are wrapped with a low boiling point solvent such as isobutane or pentane with a resin such as vinyl chloride copolymer, acrylonitrile resin, acrylic acid ester or methacrylic acid ester. It is a granule in the form of capsule made of fine particles of 5 ~ 50㎛ size, and it is expanded to 4 ~ 5 times its diameter without releasing foam gas to the outside when it is heated at 100 ℃ ~ 150 ℃ for several minutes according to the product specification. It is a capsule-type foam that expands 50 to 100 times in volume, and since foam is independently present after foaming, the foaming cell is very uniform and a continuous bubble is not formed, so its elasticity is high and its tensile strength is not reduced. Can be arbitrarily adjusted and 5-100 weight part can be contained in resin as needed.

As such a microcapsule type foaming agent, there is a product sold under the trade name of Micro Spare as a product of Matsumodo Yuji Co., Ltd. in Japan.

5 to 100 parts by weight of the thermally expandable microcapsules were mixed with 100 parts by weight of the resin solution having a solid content of 30 to 50% by dissolving the solvent-soluble resin described above, and then placed on a knife (on both sides of the release paper). Knife) or a comma coater is applied to a thickness of about 30 ~ 100㎛, dried at 70 ~ 80 ℃ below the foaming temperature to obtain a film of 10 ~ 60㎛ thickness and then coated with a known acrylic or rubber adhesive on one side Dry it to have a pressure-sensitive adhesive layer having a thickness of 20㎛ or more, and form the pressure-sensitive adhesive layer on the back side in the same way, and then foamed by heating it to 100 ℃ ~ 150 ℃, while the intermediate resin layer is foamed, about 0.2㎛ ~ 1.5㎛ A double sided tape can be obtained. At this time, since the foamed resin layer and the adhesive are in contact with each other in a soluble state, the adhesive surface itself is welded, and thus the adhesive and the foamed resin layer surface are united even after heating and foaming, so that peeling is almost impossible. Therefore, a phenomenon such as layer separation does not occur.

In particular, the film thickness of the base material containing the microcapsule foaming agent can be arbitrarily adjusted in a coating process, and the thickness of a foam layer can be adjusted to 0.5 mm or less. Conventionally, since foam sheet is manufactured separately or used by skiving, it is not technically impossible to skive to 0.5 mm or less, and it is almost impossible to handle it for use as a tape substrate. Could not be prepared.

Next, an Example is given and this invention is demonstrated concretely.

Example 1.

Preparation of Double-coated Adhesive Tape Based on Acrylic Copolymer

end. Preparation of Acrylic Resin Copolymer

○ Composition of monomer (100 parts by weight)

Methyl methacrylate (MMA): 40 parts by weight

Butyl acrylate monomer (BAM): 20 parts by weight

Acrylic acid: 8 parts by weight

2-hexylethyl acrylate monomer (2HEAM): 10 parts by weight

Ethyl acrylate monomer (EAM): 17 parts by weight

2-hydroxyethyl methacrylate (2HEMA): 3 parts by weight

-Benzoyl peroxide (BPO): 2 parts by weight

○ Composition of solvent (100 parts by weight)

Ethyl acetate (EA): 80 parts by weight

Toluene: 10 parts by weight

-Isoprofil alcohol (IPA): 5 parts by weight

Methanol: 5 parts by weight

○ Synthesis of Acrylic Resin Copolymer

After mixing 100 parts by weight of the monomer to 100 parts by weight of the solvent and refluxing at 70 to 80 ° C. for about 8 hours, polymerization is initiated by benzoyl peroxide as a polymerization initiator, thereby obtaining an acrylic copolymer having a solid content of 50%.

I. Production of Tape Base Material

○ 20 parts by weight of a microcapsule-type blowing agent (manufactured by Matsumodo Yuji Co., Ltd., brand name Microsphere) is mixed with 100 parts by weight of the acrylic copolymer (50% of solid content).

All. Manufacture of Double Sided Adhesive Tape

The tape base material is applied on a double-sided release paper in a thickness of 70 μm and then dried at 80 ° C. or lower to form a resin containing a foaming agent on the release paper in a film form.

A well-known acrylic resin-based pressure-sensitive adhesive having a solid content of 40% is applied to the thermally expandable film-like base resin, followed by drying at 80 ° C. or lower so that the thickness of the pressure-sensitive adhesive layer is about 30 μm. While the release paper is laminated thereon, the cross-sectional release paper on the opposite side of the base resin film is rolled up and peeled off, and the wound is unrolled again to allow the heat-expandable base resin film layer to come up, coated with a known acrylic adhesive, dried at 80 ° C. or lower, and the adhesive thickness 30 It was formed to a ㎛ and passed through a 125 ℃ heat dryer for 2 minutes so that the thermal expansion microcapsules in the substrate layer was foamed to prepare a double-sided tape having a thickness of 0.6mm foam base layer.

In addition, as described above, the pressure-sensitive adhesive layer is not coated directly on the base resin film, and the pressure-sensitive adhesive layer is separately coated and dried on the release paper layer, then laminated on both sides of the dried base resin film, and then foamed with a window scoop through a 125 ° C. heat dryer. A double sided adhesive tape having a thickness of 0.6 mm was made.

Example 2.

Preparation of double-sided adhesive tape based on rubber

○ base material

SIS: 100 parts by weight

AN rubber: 20 parts by weight

○ Solvent (mixed solvent)

Toluene: 50 parts by weight

Methyl ethyl ketone: 50 parts by weight

Cyclohexane: 80 parts by weight

○ Microcapsule foaming agent: 20 parts by weight

(A brand name: micro pair, Japan Matsumodo oil company product)

○ After dissolving 120 parts by weight of rubber in 180 parts by weight of the mixed solvent, stirring and dissolving it, adding 20 parts by weight of microcapsular foaming agent and mixing them uniformly, coating and foaming in the same manner as in Example 1 A double-sided adhesive tape having a foam base layer was prepared.

Comparison of Properties of Double-Sided Adhesive Tape materials Acrylic resin system Rubber system adhesive Acrylic system Rubber system Acrylic system Rubber system Tensile Strength (g · f) 750 750 800 800 Adhesive force (gf) 600 700 600 700 ※ Sample: Double sided adhesive tape with thickness of 600㎛ including adhesive layer and width of 1cm

Adhesion can be changed depending on the type of adhesive.

The double-sided pressure-sensitive adhesive tape prepared by the method of the present invention does not cause a layer separation problem between the tape base material and the pressure-sensitive adhesive layer, and the double-sided pressure-sensitive adhesive tape in which the conventional tape base material is a foamed elastic body separately forms a tape base material, and then forms an adhesive layer thereon. Since the thickness of the tape base material was about 0.5 mm, it could not be manufactured and it was difficult to handle it, so that the whole double-sided adhesive tape (including the release paper) could not be manufactured with a thickness of 1 mm or less. The thickness of 0.5mm (500㎛) or less, the thickness of the entire tape is 1mm or less has the advantage that can be produced arbitrarily.

Claims (3)

In the method for producing a double-sided adhesive tape whose tape base material is a foamed polymer elastomer sheet, a polymer solution containing a microcapsule foaming agent is applied on a release paper and dried to form a polymer elastic film, and then an adhesive is applied to both sides of the polymer elastic film. A method of producing a double-sided adhesive tape based on a foamed elastomer elastomer having a pressure-sensitive adhesive layer on both sides by drying the foamed layer to form a pressure-sensitive adhesive layer and laminating a release paper on both sides of the pressure-sensitive adhesive layer. According to claim 1, wherein the polymer elastomer is acrylic copolymer resin, nitrile rubber (Nitril Rubber), Chloroprene rubber (Chloroprene rubber), Acrylonitrile rubber (Acrylonitril Rubber), Styrene-butadiene-Rubber, Styrene Styrene-isoprene-Styrene rubber, Styrene-butadirene-styrene rubber, Ethylene vinyl acetate copolymer, Ethylene acrylate copolymer, Copolymer of vinyl chloride and vinyl isobutyl ether, Polyurethane Method of producing a double-sided adhesive tape selected from cellulose acetate. The method of manufacturing a double-sided pressure sensitive adhesive tape according to claim 1, wherein the pressure sensitive adhesive is an acrylic pressure sensitive adhesive or a rubber pressure sensitive adhesive.