KR960014762B1 - Process for the preparation of adhesive film - Google Patents

Abstract

spreading regularly adhesive resin on the surface of the polyester film; adding silane compound in the reaction product of acryl group resin and isocyanate group hardening agents, and the surface is covered with that mixed adhesive solution and stacked with a deformed film. The isocyanate group hardening agents and the silan compound are used in the ratio of 2-5 wt% and 0.05-0.2 wt% against acryl group resin 100 wt%.

Description

Manufacturing Method of Adhesive Film

According to the present invention, the adhesive film is uniformly coated on the surface of the polyester film, and then an adhesive layer is formed on the adhesive resin and a release film layer is formed thereon. It is about a method.

In general, the adhesive film is composed of a base film such as plastic, a pressure-sensitive adhesive layer for adhesion with the adherend, and a release film layer for protecting the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive film based on the polyester film has excellent polyester film. Mechanical, chemical, and optical properties, ie, strength, dimensional stability, heat resistance, chemical resistance, transparency, weather resistance, etc. are widely used in various industrial applications, mainly electric and electronic.

For example, there are many uses such as advertisements such as various labels and stickers, name plates such as electric and electronic devices, electrical insulation parts, various building structures, and fastening materials for transportation.

However, the pressure-sensitive adhesive film used for a wide range of applications as described above should be excellent in time stability and thus re-peelability that the adhesive force of the pressure-sensitive adhesive does not change with time. In other words, if the stability over time, the pressure-sensitive adhesive layer adheres to the adherend, such that the pressure-sensitive adhesive is transferred to the adherend according to conditions such as temperature, humidity, gas pressure, etc., or the adhesive deteriorates, resulting in poor adhesive strength. For example, if various advertisement stickers are placed on the window glass, the adhesive is transferred to some adherends according to the solar heat, air, pressure and time, and the window glass is contaminated, and when the sticker is peeled off and another sticker is attached, The cumbersome work of removing and re-sticking the adhesive is necessary.

Moreover, when the adhesive force of a polyester film and an adhesive layer and the adhesive force of a to-be-adhered layer and an adhesive layer are the same, a problem arises that it does not fall easily at the time of peeling. Accordingly, it is an object of the present invention to provide an adhesive film having excellent aging stability and re-peelability.

In order to achieve the above object as well as another object that is easily expressed, in the present invention, an acrylic resin and an isocyanate-based curing agent are reacted, and then an adhesive resin phase uniformly coated on the polyester film surface is mixed with a silane compound. It was possible to obtain a pressure-sensitive adhesive film having excellent aging stability and re-peelability by being applied to.

The adhesive film of the present invention can be used by attaching it to a metal surface, a plastic surface, a glass plate, etc. The adhesive film of the present invention is an adhesive force (A) between a polyester film and an adhesive layer coated with an adhesive resin uniformly on the surface, A pressure-sensitive adhesive layer in contact with the release film surface was applied to the adherend, and the initial adhesion force (B) after 30 minutes and the permanent adhesion force (C) after 1 day were (A)> (C)> (B), and (C) ≤1.4 (B) It has the characteristics which are excellent in aging stability and re-peelability.

The present invention will be described in more detail as follows.

The adhesive film of the present invention is prepared by reacting an acrylic resin and an isocyanate curing agent on an adhesive resin uniformly coated on a polyester film surface, applying a silane compound, and then mixing and mixing a pressure-sensitive adhesive liquid and laminating a release film.

The adhesive resin in the present invention may be used alone or in combination with a resin having an adhesive force commonly used in the art to which the present invention belongs, such as acrylic resins, urethane resins, copolyester resins, and the like.

As the acrylic resin in the present invention, acrylic esters, methacrylic acid esters alone or copolymers thereof, or mixtures thereof may be used, and acrylic esters include methyl acrylate, ethyl acrylate, butyl acrylate, and the like. Methyl, ethyl methacrylate, butyl methacrylate and the like. It is preferable that an acryl-type resin is about 10,000-100,000 in molecular weight, in order to improve the compatibility with isocyanate hardening | curing resin.

As isocyanate hardening | curing agent in this invention, 2, 4- trans diisocyanate, 2, 6- trienedi isocyanate, m-phenylenedi isocyanate, p-phenylenedi isocyanate, 1-chlorophenylene-2, 4- diisocyanate, or phenols The isocyanate compound which stabilized the said isocyanate compound with blocking agents, such as an alkali phenol, lactam, and a basic nitrogen compound, and regenerated the isocyanate group by heating etc. can be used.

Moreover, as an isocyanate compound, it is also possible to use the said isocyanate compound as some kind of mixture. Isocyanate-based curing agent made of such a good molecular weight of about 1,000 ~ 30,000. It is effective to add 2 to 5 parts by weight based on 100 parts by weight of the isocyanate-based curing agent, and when the added amount is 2 parts by weight or less, re-peelability is poor, and when 5 parts by weight or more, there is a problem that the adhesive strength is lowered.

On the other hand, the silane compound has a -Si (OCH ₃ ) ₃ structure, vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxy Propyltrimethoxysilane, β (3,4-epoxycyclohexyl) ethyl trimethoxy silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy propylmethyldiethoxysilane, N-β (aminoethyl ) 1 type, or 2 or more types can be mixed and used with (gamma) -aminopropyl trimethoxysilane, (gamma) -aminopropyl triethoxysilane, (gamma) -methyl gaptopropyl trimethoxysilane, and (gamma) -chloropropyl trimethoxysilane.

The silane compound is preferably added in an amount of 0.05 to 0.2 parts by weight based on 100 parts by weight of the acrylic resin, and when the amount is 0.05 parts by weight or less, aging stability is lowered, and when it is 0.2 parts by weight or more, re-peelability and adhesion are problematic. In addition, natural rubber, isoprene rubber, styrene butadiene rubber, butyl rubber, and rosin, rosin derivative, Tefrene resin, petroleum resin, etc. may be used as a rubber-based adhesive for imparting tackiness, and the adhesive includes dyes, heat stabilizers, and flame retardants. , The heat resistance improver and the like can be added to improve its function.

As a base material used for this invention, the plastic film especially the polyester film was mainly used. The thickness of the polyester film was 12 to 250 microns, and a turbidity of 0.3 to 15% was used based on 100 microns.

As the surface coating method of the adhesive resin used in the present invention, a well-known Meyer bar coating method, KISS coating method, direct gravure coating method, reverse gravure coating method and the like can be used. Mayer coating method, gravure coating method, reverse roll coating method, comma coating method, micron bar coating method and the like can be used.

In the present invention, the thickness of the surface coating layer of the adhesive resin is effective to 0.01 ~ 0.2㎛, preferably 0.02 ~ 0.1㎛ after drying, the thickness of the adhesive layer is 5 ~ 50㎛ preferably 15 ~ 35㎛ after drying It is effective to be.

The adhesive film produced in the present invention has excellent secular stability and re-peelability, and is widely used for advertisements such as various labels and stickers, nameplates for electrical and electronic devices, electrical insulation parts, various construction structures, and fastening materials. Can be.

In the present invention, each characteristic value was obtained by the following method.

1) adhesion

In accordance with JIS Z 0237, a sample having a width of 25 mm was fixed using a surface tester manufactured by Japan Tester Industries Co., Ltd., and then peeled 180 ° at 300 ± 30 m / min to measure initial adhesion and permanent adhesion. Here, the initial adhesive force is when the adhesive layer is applied to the workpiece, and peeled off after 30 minutes, and the permanent adhesive force is adhesive force when peeling off after 1 day.

2) holding force

In accordance with JIS Z 0237, the adhesive film is adhered to a stainless steel plate and placed in a 100 ° C thermostat, and a 1 kg load is applied to indicate the time or distance traveled in mm from the test plate.

3) TACK

According to JIS Z 0237, the number of steel balls rolled farthest without falling off the test plate by using a ball-tack tester (BALL TACK TESTER) manufactured by Samyoung Ink Co., Ltd. is used as a tack value.

4) re-peelability

When the adhesive film is peeled off after 60 days after being adhered to the adherend, when the adhesive layer is 100% peeled off without being transferred to the adhered surface, when 0, 10% or less is transferred △, when transferred more than 10%, X Indicated.

The following examples and comparative examples specifically illustrate the invention, but do not limit the scope of the invention.

Example 1

80 g of a solution of ethyl acetate and toluene mixed 1: 1 was prepared, and 100 g of Tokyo Ink BPS-4891 was added as a solvent-based acrylic adhesive and stirred for 30 minutes, and then 2.5 g of Tokyo Ink BHS-8515, an isocyanate-based hardener, as a curing agent. After stirring for 30 minutes and thoroughly mixed, 0.1g of KBM 703 manufactured by Shinwol Chemical was added as a silane compound, and stirred for 30 minutes to prepare an adhesive solution. XG-531 of Cheil Synthetic Co., Ltd., a biaxially stretched polysilicon film, was applied to 100 μm on one side and uniformly coated with adhesive resin, and then the adhesive solution was applied using a Mayer bar to make the thickness 23 μm. An adhesive film was prepared by laminating a release film of 38 μm. The characteristic evaluation about the obtained film is shown in Table 1.

Example 2

A pressure-sensitive adhesive film was prepared in the same manner as in Example 1, except that 3.5 g of a curing agent was used, 0.15 g of a silane compound, and the pressure-sensitive adhesive layer was dried to 24 μm. The characteristic evaluation result about the obtained film is shown in Table 1.

Example 3

A pressure-sensitive adhesive film was prepared in the same manner as in Example 1, except that 5.0 g of a curing agent, 0.20 g of a silane compound, and a pressure-sensitive adhesive layer of 24 μm were dried. The characteristic evaluation result about the obtained film is shown in Table 1.

Example 4

An adhesive film was prepared in the same manner as in Example 1 except that the adhesive layer had a thickness of 15 μm after drying. The characteristic evaluation result about the obtained film is shown in Table 1.

Example 5

An adhesive film was obtained in the same manner as in Example 1 except that 0.05 g of the silane compound was used and the adhesive layer was dried to 22 μm. The characteristic evaluation result about the obtained film is shown in Table 1.

Comparative Example 1

An adhesive film was obtained in the same manner as in Example 1 except that XG-500 of Cheil Synthetic Co., Ltd., a biaxially stretched polyester film, was used as the base film and no adhesive resin was applied. The characteristic evaluation result about the obtained film is shown in Table 1.

Comparative Example 2

An adhesive film was prepared in the same manner as in Example 1 except that the silane compound was not added in Example 1. The characteristic evaluation result about the obtained film is shown in Table 1.

Comparative Example 3

An adhesive film was prepared in the same manner as in Example 2, except that no silane compound was added. The characteristic evaluation result about the obtained film is shown in Table 1.

Claims (2)

Adhesive resin is uniformly applied on the surface of polyester film, then acrylic resin and isocyanate-based curing agent are reacted, and then a pressure-sensitive adhesive liquid mixed with silane compound is applied and a release film is laminated to uniformly apply adhesive resin to the surface. The adhesive force (A) between the polyester film and the pressure-sensitive adhesive layer applied to the pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer were applied to the adherend, and the initial adhesive force (B), which is the adhesive force after 30 minutes, and the pressure-sensitive adhesive layer were applied to the adherend, and the permanent adhesive force after 1 day (C) The relationship is (A)> (C)> (B), and (C) ≤1.4 (B) The manufacturing method of the adhesive film characterized by the above-mentioned. The method of claim 1, wherein the amount of isocyanate curing agent and silane compound is 2 to 5 parts by weight and 0.05 to 0.2 parts by weight with respect to 100 parts by weight of the acrylic resin, respectively.