JPH07216317A - Pressure-sensitive adhesive tape - Google Patents

Abstract

PURPOSE:To obtain the subject tape which suffers neither substrate deterioration nor adhesive deterioration even when the tape adherent to an adherend is exposed to sunlight for long and which leaves little adhesive residue after being peeled from the adherend by forming a specific sealing layer on one side of a porous substrate and forming a pressure-sensitive adhesive layer on the other side, CONSTITUTION:A sealing layer 1 which contains 0.1-40wt.% inorganic particles having an average particle diameter of 1-100nm and capable of absorbing or scattering ultraviolet (e.g. titanium oxide particles) (and further contains, e.g. a vinyl acetate resin) is formed on one side of a porous substrate 2 (e.g. a nonwoven fabric) in such a manner that part of the layer 1 penetrates into the substrate 2. An adhesive layer 3 made of, e.g. natural rubber and a poly((beta- pinene) resin is formed on the other side of the substrate 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive tape using a porous base material, and more specifically, it deteriorates the base material and the pressure-sensitive adhesive even after being attached to an adherend and exposed to sunlight for a long period of time. In addition, the present invention relates to an adhesive tape that is less likely to cause adhesive residue even when peeled off from an adherend, and is particularly suitable for construction site construction and masking.

[0002]

2. Description of the Related Art At construction sites during construction, adhesive tapes are used for masking such as painting and for various purposes.
In order to improve the hand-tearability of such adhesive tape, paper, woven cloth, or non-woven fabric is used as a base material, and an adhesive layer is formed on one surface of the base material and a sealing layer formed by a synthetic resin laminate on the other surface. Is provided.

Japanese Unexamined Patent Publication No. 4-153287 discloses a surface protective film obtained by coating a pressure sensitive adhesive on a polyolefin resin film containing 0.1 to 10 parts by weight of titanium oxide or zinc oxide. .

[0004]

The above-mentioned adhesive tape used at a construction site is often exposed to sunlight outdoors.
The sealing layer is formed by extruding and laminating a simple resin such as polyethylene, and ultraviolet rays are transmitted therethrough. Therefore, since the base material and the adhesive are deteriorated by the ultraviolet rays of the sunlight that has passed through the base material of the adhesive tape, the base material is easily broken,
The laminate layer and the base material are separated. Further, when the used adhesive tape is peeled off from the adherend, an adhesive residue is left on the adherend and it becomes unsightly.

Since the surface protective film described in Japanese Patent Laid-Open No. 4-153287 is attached to the surface of an article, it is not required to be hand-tearable as an adhesive tape. or,
This does not provide a high degree of adhesion between the porous base material of the adhesive tape and the laminate layer, that is, the sealing layer.

The present invention solves the above-mentioned conventional problems and protects the base material and the adhesive layer from deterioration due to ultraviolet rays by means of a sealing layer applied and dried on the surface of the porous base material, and the sealing layer and the base material are protected. It is an object of the present invention to provide a pressure-sensitive adhesive tape that has excellent adhesive strength with and hand tearability and has little adhesive residue on an adherend.

[0007]

The pressure-sensitive adhesive tape of the present invention is a pressure-sensitive adhesive tape comprising a porous base material having a sealing layer on one side and an adhesive layer on the other side.
The average particle diameter of nm is 0.1 to 40 parts by weight of an inorganic powder having an ultraviolet absorbing or scattering effect, and a part of the sealing layer is impregnated in the porous base material. It is characterized by.

The base material of the pressure-sensitive adhesive tape of the present invention is a non-woven fabric or woven fabric composed of synthetic resin fibers such as polyethylene, polypropylene, polyester, vinylon, etc., or cellulosic fibers,
It is a porous material such as paper.

Examples of the inorganic powder having an ultraviolet absorbing or scattering effect contained in the sealing layer laminated on the above-mentioned base material include titanium oxide and zinc oxide. The inorganic powder has an average particle size of 100 nm or less, and the average particle size is calculated by measuring the specific surface area and assuming that the inorganic powder is a sphere.

If the average particle size exceeds 100 nm, it blocks visible light and becomes opaque, so the average particle size must be 100 nm or less. This gives transparency to the sealing layer,
Color matching can be easily performed when printing.

When the content of the inorganic powder is less than 0.1 parts by weight, there is no effect of absorbing or scattering ultraviolet rays,
If it exceeds 40 parts by weight, the dispersibility will deteriorate, so
The range is 40 parts by weight. However, it is preferably 0.1 to 10 parts by weight in order to form a sealing layer having good transparency.

The sealing layer of the pressure-sensitive adhesive tape of the present invention is, for example, an emulsion in which a resin component such as vinyl acetate is dispersed in water,
Alternatively, it is formed by forming a solvent solution in which a resin component is dissolved in a solvent, and directly coating and drying a base material with a coating agent in which a predetermined amount of the above inorganic powder is mixed.

By directly applying the above-mentioned liquid coating agent to the cloth base material, a part of the coating agent is impregnated into the cloth base material until it is dried, and when it is dried in that state, one part of the sealing layer is formed. The part digs in between the fibers of the cloth base material to form a laminate having high adhesive strength. Therefore, it has a strong lamination strength which cannot be obtained by the sealing layer formed by lamination which has been conventionally performed. As is known for an adhesive tape using a cloth or the like as a base material, the higher the adhesive strength between the sealing layer and the base material, the better the hand tearability.

When a liquid such as an emulsion is used like the above-mentioned coating agent, the inorganic powder becomes a core when the emulsion gels, the film-forming property is improved, and it is mixed with a resin and extruded and laminated. Alternatively, it is also possible to mix a larger amount of the inorganic powder than that which is attached as a film.

[0015]

The adhesive tape of the present invention comprises 0.1-40 parts by weight of an inorganic powder that absorbs or scatters ultraviolet rays in the sealing layer, so that ultraviolet rays reach the layer, the cloth substrate and the adhesive layer. Are prevented and protect them from deterioration due to ultraviolet rays. As a result, peeling between the sealing layer and the base material layer and between the base material layer and the pressure-sensitive adhesive layer is less likely to occur.

The average particle size of the inorganic powder is 1-40.
Since the fine particles are 0 nm, transparency is imparted to the filling layer, and the work of color matching can be easily performed when printing on the surface of the filling layer.

Further, since the filling layer is provided by directly applying and drying the liquid coating agent on the porous substrate,
Part of it is impregnated into the porous substrate and solidified, and the adhesive strength between the two becomes very high. This results in an adhesive tape with excellent hand tearability.

By making the filling layer laminated on the substrate a liquid such as an emulsion, the inorganic powder becomes a core when the emulsion gels, the film-forming property is improved, and a larger amount than that when mixed with the resin. It is also possible to mix inorganic powders.

[0019]

Embodiments of the adhesive tape of the present invention will now be described with reference to the drawings. (Example) FIG. 1 is a cross-sectional view showing an example of the pressure-sensitive adhesive tape of the present invention, in which 1 is a nonwoven fabric sheet obtained by mixing pulp fibers, Manila hemp fibers, and vinylon fibers, and binding the fibers with polyvinyl alcohol as a binder. Is.

A sealing layer 2 is laminated on the surface of the non-woven sheet 1, and the non-woven sheet 1 is partially impregnated with the sealing layer 2. The filling layer 2 was formed as follows. 1
A polymerization catalyst was added to a polyvinyl alcohol aqueous solution of ˜5% by weight, and a vinyl acetate resin was added dropwise while maintaining the temperature at 60 ° C. or higher, and the emulsion was polymerized by stirring to obtain acetic acid having a solid content of 40 parts by weight based on 100 parts by weight of the solution. A vinyl emulsion was obtained (coating agent 1).

Next, 20 parts by weight of titanium oxide having an average particle size of about 80 nm was slurried and dispersed in the above emulsion while stirring (coating agent 2). The coating agent 2 is applied to the surface of the non-woven fabric sheet 1 with an applicator, and 10
1 minute drying in an oven heated to 0 ° C., allowed to film formation to form a the sealing layer 2 of 15 g / m ² as solids.

After that, the pressure-sensitive adhesive layer 3 was formed by coating and drying the pressure-sensitive adhesive having the following composition on the other surface of the non-woven fabric sheet 1 on which the sealing layer 2 was formed so that the solid content was 30 g / m ^2. Laminated. Natural rubber (Pale crepe) 100 parts by weight Poly β-pinene resin 75 parts by weight Petroleum oil 5 parts by weight Polymerized trimethylhydroquinone 2 parts by weight Toluene 400 parts by weight

(Comparative Example 1) An adhesive tape was obtained in the same manner as in Example except that only the coating agent 1 was used as the sealing layer.

(Comparative Example 2) Titanium oxide of coating agent 2 was changed to 5
Although 0 part by weight was dispersed in the coating agent 1, it could not be uniformly dispersed.

The pressure-sensitive adhesive tapes of Example and Comparative Example 1 were set to 25 mm.
Cut to a size of 100 mm, crimp it to a glass plate, install it in a sunny indoor room facing south, and peel it off at a constant speed with a shopper at a constant rate of 10 pieces for each number of days elapsed, and the adhesive remains on the glass plate surface. The number of printed sheets was checked and evaluated. The results are shown in Table 1.

[0026]

[Table 1]

As is clear from Table 1, in the examples, the amount of adhesive residue on the glass plate was small even after the lapse of days, and the deterioration of the adhesive was small. On the other hand, it can be seen that in Comparative Example 1, the adhesive residue has already been formed in most of the one day and the deterioration of the pressure-sensitive adhesive is extremely advanced. Further, in the example, the adhesion between the base material and the sealing layer was perfect even after the lapse of days, and the hand tearability was good, but in the comparative example 1, the base material and the sealing layer were partially peeled off. There was something I started, and it wasn't easy to cut.

[0028]

The adhesive tape of the present invention has the above constitution,
Since the sealing layer contains 0.1 to 40 parts by weight of an inorganic powder that absorbs or scatters ultraviolet rays, the layer, the cloth substrate and the pressure-sensitive adhesive layer are protected from deterioration by ultraviolet rays. As a result, the adhesive strength between the sealing layer and the base material layer and between the base material layer and the pressure-sensitive adhesive layer does not decrease, and the adhesive residue on the adherend is also reduced.

The average particle size of the inorganic powder is 1-40.
Since the fine particles are 0 nm, transparency is imparted to the filling layer, and the work of color matching can be easily performed when printing on the surface of the filling layer.

Further, since the sealing layer is provided by directly coating and drying the liquid coating agent on the cloth base material, a part of it is impregnated into the cloth base material and solidified, and the adhesive strength between the two is very high. As a result, it becomes an adhesive tape with high tearability.

[0031]

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the adhesive tape of the present invention.

[Explanation of symbols]

 1: Nonwoven sheet 2: Sealing layer 3: Adhesive layer

Claims (1)

[Claims] 1. A pressure-sensitive adhesive tape comprising a porous substrate having a sealing layer on one surface and an adhesive layer on the other surface, wherein the sealing layer has an average particle diameter of 1 to 100 nm and absorbs ultraviolet rays or An adhesive tape comprising 0.1 to 40 parts by weight of an inorganic powder having a scattering effect, and a part of the sealing layer being impregnated in the porous base material.