JP2872328B2 - Production method of adhesive film - Google Patents

Description

The present invention relates to a method for producing a pressure-sensitive adhesive film, and particularly to a method for producing a decorative pressure-sensitive adhesive film.

[Related Art] In recent years, decorative adhesive films have been widely used in place of painting. The decorative adhesive film is an adhesive film having a predetermined shape on which characters, designs, and the like are printed in advance. Therefore, it is simpler than painting, and is particularly effective when displaying the same pattern, mark, etc. on a large number of objects to be decorated. However, due to the use of the adhesive film, it is difficult to correct when the crimping position is different, the film after crimping is apt to wrinkle, air tends to remain between the adherend and the adhesive film, etc. There are drawbacks.

In order to improve these points, an adhesive film in which a non-adhesive substance is distributed on the adhesive surface of the adhesive film has been developed.
44-3120 and JP-A-58-N13682. In these methods, little adhesive force is generated when the adhesive film is simply in contact with the adherend, and the adhesive film is firmly adhered to the adherend only when strongly pressed, thereby improving the workability of the adhesive. It is a thing. The former disperses a friable hollow non-sticky substance on a thermoplastic coating layer on kraft paper and electrostatically holds it, and it is about 13
The non-adhesive substance is half-pushed into the coating layer by heating and pressing at 0 ° C., and then the adhesive is applied,
It is manufactured by crimping a film. The latter disperses a non-hollow solid non-tacky substance on release paper,
It is manufactured by applying an adhesive on it and pressing a vinyl chloride film.

[Problems to be solved by the invention]

Since the adhesive strength at the time of contact between the adhesive film and the adherend depends on the degree of dispersion of the non-adhesive substance, its controllability directly affects the workability of the film adhesion. However, in each of the above-mentioned conventional techniques, since the non-adhesive substance is dispersed on the release paper, it is difficult to control the dispersibility.

Further, in the prior art, the non-viscous substance is limited to a hollow solid in the former and a non-hollow solid in the latter, and a substance which is liquid at the time of dispersion cannot be used. Moreover, in the former, the release paper is limited to a two-layered structure having a thermoplastic coating layer, and furthermore, a 100%
There is a drawback that a high-temperature pressing step at a temperature of not less than ° C is required.

The present invention solves such conventional disadvantages, and disperses a wide variety of non-adhesive substances on an adhesive with good dispersion control,
Moreover, an object of the present invention is to provide a method for producing an adhesive film which does not require high-temperature pressurization.

[Means for solving the problem]

The method for producing a pressure-sensitive adhesive film according to the present invention includes a step of forming a large number of concave portions on at least one surface of the release paper; a step of applying a non-tacky substance to the surface where the large number of concave portions are formed; Removing excess non-stick material from the surface to which the material is applied and filling only the plurality of recesses with non-stick material; and adhering to the surface of the release paper on the side where the non-stick material is filled. A step of applying an agent and a step of pressing a substrate onto the pressure-sensitive adhesive-coated surface of the release paper.

(Operation)

In the present invention, a large number of concave portions having a predetermined shape and distribution are previously formed on the surface of the release paper, and the concave portions are filled with a non-adhesive substance, and then an adhesive is applied. Therefore, the distribution of the non-adhesive substance on the adhesive can be controlled in advance. Further, the substance to be filled in the recess may be liquid at the time of filling and can be solidified later, so that the selection range of the unfilled substance can be significantly expanded.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to examples.

FIG. 1 is a schematic sectional view of an adhesive film for explaining the present invention.

In the present invention, concave portions 1A having a predetermined shape are formed in release paper 1 with a predetermined distribution using an embossing roll or a press machine. As the release paper 1, for example, any of those commonly used for adhesive films such as glassine paper, clay-coated paper, and polyethylene laminated paper that have been subjected to a release treatment can be used. The shape and distribution of the concave portions are appropriately selected according to the adhesive strength of the adhesive used and the conditions of use of the adhesive film. Next, the non-adhesive substance is filled in the concave portion. Non-stick materials include silica, alumina, titanium oxide, calcium carbonate, molybdenum disulfide, calcium hydroxide and other inorganic fine particles, sulfide rubber, ebonite, styrene resin and other organic fine particles, glass beads, various microcapsules, etc. In addition to the solid fine particles such as the hollow fine particles described above, it is possible to use a substance which is liquid at the time of filling with an ultraviolet curable resin, a thermosetting resin, or the like, and which is solidified by the treatment after filling. When the above-mentioned solid fine particles are used, the fine particles are dispersed in an appropriate dispersion medium such as water or alcohol to form a slurry, and the slurry is applied to the surface of the release paper 1 provided with the concave portions 1A, and then a squeezer or a spatula is used. The excess slurry is wiped off by the
So that it only exists within Next, if necessary, the release paper is heated to 40 to 50 ° C. to evaporate the dispersion medium. When the non-adhesive substance is an ultraviolet-curable resin or a thermosetting resin, an uncured liquid resin is applied to the surface of the release paper provided with the concave portions, and then the excess resin is removed, and the concave portions are irradiated with ultraviolet light or heated. The resin filled in is cured and solidified. Next, the adhesive 3 is applied to the surface of the release paper 1 in which the concave portions 1A are filled with the non-adhesive substance 2 in this manner. The pressure-sensitive adhesive may be selected from pressure-sensitive adhesives commonly used for pressure-sensitive adhesive films, such as acrylic pressure-sensitive adhesives and styrene-butadiene block copolymers, which are suitable for the intended use, and may be applied according to a conventional method. Next, the surface substrate 4 and the release paper coated with the pressure-sensitive adhesive 3 are pressure-bonded in a conventional manner. As the surface substrate, polyvinyl chloride (PVC), a copolymer of acrylic acid ester, polyvinyl fluoride (PVF), polyurethane or the like is used.

 Next, specific examples of the present invention will be described.

Example 1 A piece of polyethylene laminated paper was used as a release paper, and a piece of 150 μm was applied to one surface thereof by an embossing roll.
Square pyramids having a depth of 30 μm were formed at a uniform density of 100 / cm ² . Then, uncured UV-curable resin UV-37
00 (manufactured by Toa Gosei) was applied, and excess resin was removed with a squeezer, and then the resin was cured by irradiating ultraviolet rays. Further, an acrylic ester-based two-part curable pressure-sensitive adhesive was applied thereon with a thickness of 32 μm, and a PVC film as a substrate was pressed. Immediately before use, the release film 1 is peeled off from the pressure-sensitive adhesive film thus prepared, and the pressure-sensitive adhesive surface is brought into contact with the adherend, as shown in FIG. At this time, since the UV curable resin, which is a non-adhesive substance, is dispersed on the surface of the adhesive 3, the adhesive film does not adhere to the adherend, and therefore, the alignment can be freely performed on the adherend. can do. After the adhesive film is properly positioned on the adherend, a pressure is applied to the adhesive film so that the film adheres firmly to the adherend.

Table 1 shows the adhesive strength of the above-mentioned examples after pressure bonding to the adherend and when they are simply brought into contact with each other, in comparison with a decorative adhesive tape in which a non-adhesive substance is not dispersed (comparative example). Here, the adherend is a coated iron plate, and the loop tack in the table is such that the tape-like adhesive film is brought into contact with the adherend as a loop with the adhesive layer on the outside, for example, a contact over a length of several cm. The force to tear off after creating a state. The initial adhesive force is the force required for peeling the adhesive film from the adherend 24 hours after the adhesive film is pressed immediately after the adhesive film is reciprocated once with a 2 kg roll.

As shown in Table 1, according to the present invention, when the adhesive film is in contact with the adherend, the adhesive strength is 0 g / 25 mm, and the adhesive film can be freely moved on the adherend. And after the pressure bonding, it adheres to the adherend with a strong adhesive force.
Therefore, according to the present invention, the workability when the pressure-sensitive adhesive film is pressure-bonded to the adherend can be significantly improved.

Example 2 Conical concave portions having a diameter of 200 μm and a depth of 50 μm were formed on the surface of the release paper at a density of 25 / cm ² . Thereafter, an adhesive film was produced in exactly the same manner as in Example 1. The adhesive properties and loop tack of this adhesive film were the same as in Example 1.

Example 3 A saturated polyester resin was applied to the concave portions of the release paper formed in the same manner as in Example 1, and excess resin was removed with a squeezer, followed by drying at 50 ° C. for 1 minute to obtain a non-adhesive substance. Thereafter, an adhesive film was produced in the same manner as in Example 1. The adhesive properties and loop tack of this adhesive film were the same as in Example 1. It should be noted that there was no change in the characteristics even when the concave portion had the same conical shape as in Example 2.

Even when clay-coated paper was used as the release paper in each of the above examples instead of poly-laminated paper, the adhesive properties and loop tack were similar.

In the above description, an example was shown in which the concave portion was processed only on one surface of the release paper and the non-adhesive substance was filled, but the processing was performed on both surfaces of the release paper, and the non-adhesive material was applied to the surface of the adhesive. Obviously, a dispersion of the agent can be formed on both sides of the release paper.

As described above, the shape and distribution of the concave portions formed on the surface of the release paper differ depending on the properties of the adhesive and the purpose of use. Under general use conditions, the depth of the concave portion, that is, the height of the non-adhesive substance from the surface of the pressure-sensitive adhesive layer is preferably in the range of 3 μm to 50 μm, and if the concave portion is shallower, the adhesive force at the time of contact is too large. If the recess is deeper than this, the aesthetic appearance of the film surface after the pressure-sensitive adhesive film is compressed is impaired. The distribution of recesses is also related to the depth of the recesses, but is generally 10 / cm ²
A range of ~ 200 pieces / cm ² is desirable.If the distribution is less than this, the adhesive strength at the time of contact is too strong.If the distribution is more dense than this, the adhesive strength at the time of crimping is weak. You will lose.

〔The invention's effect〕

As described above, according to the present invention, the concave portion is formed in advance on the release paper, and the non-adhesive substance is filled therein, so that the distribution of the non-adhesive substance can be controlled. The adhesive force at the time of contact with and after pressure bonding can be sufficiently controlled. Further, according to the present invention, not only solid fine particles but also a liquid substance which is solidified by a subsequent treatment can be used as the non-adhesive substance.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an adhesive film for explaining the method of the present invention, and FIG. 2 is a schematic cross-sectional view showing a state in which a release paper is peeled from the adhesive film of the present invention. 1 ... release paper, 1A ... recess, 2 ... non-adhesive substance, 3 ... adhesive, 4 ... surface substrate.

Continuation of front page (72) Inventor Noriko Sato 7-7-3 Tsuji, Urawa-shi, Saitama FSK Urawa-ryo (56) References JP-A-52-78540 (JP, A) JP-A-3-177474 (JP) , A) Japanese Utility Model Showa 56-60744 (JP, U) Japanese Utility Model Showa 62-93346 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) C09J 7/00-7/04

Claims (1)

(57) [Claims] A step of forming a plurality of recesses on at least one surface of the release paper; a step of applying a non-adhesive substance to a surface on which the plurality of recesses are formed; and applying the non-adhesive substance. A step of removing excess non-adhesive substance from the surface and filling only the plurality of recesses with non-adhesive substance, and a step of applying an adhesive on a surface of the release paper on which the non-adhesive substance is filled And a step of pressing a base material onto the pressure-sensitive adhesive-coated surface of the release paper.