JPH0812955A - Adhesive tape - Google Patents

Abstract

PURPOSE:To provide an adhesive tape which is dispensed with an extra step of forming a releasing agent layer on the back of the support, does not suffer from lowered adhesiveness due to the migration of the releasing agent and is reduced in the force for rewinding from a winding. CONSTITUTION:This tape is an adhesive tape prepared by forming an adhesive layer on either surface of a support made of a nonwoven fabric, wherein the adhesive layer is formed from an organic solvent solution of an acrylic adhesive, and the nonwoven fabric contains at least 30wt.% rayon.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a plaster for medical use,
The present invention relates to a pressure-sensitive adhesive tape used as a patch or the like and used as a packaging material for industrial or general office use, and more specifically, relates to a non-woven single-sided single-sided pressure-sensitive adhesive tape of a non-woven fabric material that reduces the spreading force from the roll. .

[0002]

2. Description of the Related Art Conventionally, a release agent layer is formed on the back surface of a base material as a method of reducing the force required for developing a single-sided small-sized one-sided pressure-sensitive adhesive tape using a non-woven fabric as a base material, when the tape is unrolled from the wound body. It is known (Japanese Patent Laid-Open No. 4-272984).
See the bulletin).

[0003]

However, in order to produce an adhesive tape having the above-mentioned release agent layer, a release agent-containing liquid is applied to the back surface of a non-woven fabric substrate and dried to form the release agent layer. There is a problem in that an extra step for forming is required, which causes an increase in cost.

Also in terms of physical properties, there is a problem that the release agent on the back surface of the base material is transferred to the pressure-sensitive adhesive to cause a decrease in the pressure-sensitive adhesiveness.

In view of the above points, the present invention does not require an extra step such as formation of a release agent layer on the back surface of the substrate, does not cause a decrease in adhesive strength due to transfer of the release agent, and is developed from a roll body. An object of the present invention is to provide an adhesive tape that can reduce the force.

[0006]

The pressure-sensitive adhesive tape according to the present invention has been devised in order to achieve the above-mentioned object. In the pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is formed on one side of a substrate made of a non-woven fabric, the pressure-sensitive adhesive is The layer is formed by applying a solution of an acrylic pressure-sensitive adhesive in an organic solvent onto a substrate, and the nonwoven fabric is 30
It is characterized by containing rayon in a content of not less than wt%.

The non-woven fabric as a base material contains rayon as an essential constituent component. The reason is that the pressure-sensitive adhesive tape according to the present invention uses the fact that the adhesive force of the acrylic pressure-sensitive adhesive shows a difference between rayon and a substance other than rayon, such as pulp or Manila hemp, to reduce the developing force from the roll. Because it is a thing. The non-woven fabric as the base material may be made of rayon alone.

The non-woven fabric may contain, in addition to rayon, pulp, Manila hemp, nylon, polypropylene, polyethylene glycol terephthalate, etc., and is composed of short fibers or long fibers of these substances alone or a mixed paper product thereof. The non-woven fabric also includes felt. The basis weight of the nonwoven fabric is preferably in the range of ^{20 to} 50 g / m ² , and more preferably 25 to 45 g / m ² .

The thickness of the non-woven fabric is preferably 60 to 150 μm.
m.

The rayon content in the non-woven fabric is 30% by weight.
Limited to the above. The reason is that the rayon content is 3
This is because if it is less than 0% by weight, the difference in the adhesive force of the acrylic pressure-sensitive adhesive described above becomes small, and the reduction of the developing force cannot be achieved. The content of pulp in the nonwoven fabric is preferably 0 to 30% by weight. The content of Manila hemp in the nonwoven fabric is preferably 0 to 30% by weight.

The acrylic pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is particularly a homopolymer or copolymer of an alkyl (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms, or the above-mentioned (meth) acrylic acid. A copolymer of an alkyl ester and another functional monomer is preferably used.

Examples of the (meth) acrylic acid ester include butyl acrylate, isobutyl acrylate, hexyl acrylate, octyl acrylate, and acrylic acid-2-
Ethylhexyl, isooctyl acrylate, decyl acrylate, isodecyl acrylate, lauryl acrylate,
Stearyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, decyl methacrylate, isodecyl methacrylate, lauryl methacrylate, stearyl methacrylate and the like are exemplified. It

Examples of the functional monomer include a monomer having a hydroxyl group, a monomer having a carboxyl group,
Examples thereof include monomers having an amide group, monomers having an amino group, and monomers having a pyrrolidone ring.
Examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate and hydroxypropyl (meth).
Examples thereof include hydroxyalkyl (meth) acrylates such as acrylates. Examples of the monomer having a carboxyl group include α, β such as acrylic acid and methacrylic acid.
-Unsaturated carboxylic acid: maleic acid monoalkyl ester such as butyl maleate: maleic acid: fumaric acid: crotonic acid. Maleic anhydride also gives the same (co) polymerization components as maleic acid. Examples of the amide group-containing monomer include acrylamide, dimethyl acrylamide, and diethyl acrylamide (alkyl (meth))
Acrylamide, N-butoxymethyl acrylamide,
Examples include N-alkoxymethyl (meth) acrylamides such as N-ethoxymethylacrylamide, diacetone acrylamide, and the like. Examples of the monomer having an amino group include dimethylaminoethyl acrylate. Examples of the monomer having a pyrrolidone ring include N-vinylpyrrolidone.

As copolymerizable monomers other than the above, vinyl acetate, styrene, α-methylstyrene, vinyl chloride, acrylonitrile, ethylene, propylene and the like can be used.

In order to produce a copolymer of (meth) acrylic acid alkyl ester, it is preferable that the total amount of the copolymerized monomer components contains (meth) acrylic acid alkyl ester in an amount of 50% by weight or more. If the proportion of the (meth) acrylic acid alkyl ester is less than 50% by weight, the pressure-sensitive adhesive does not exhibit sufficient tackiness. More preferably, the proportion of (meth) acrylic acid alkyl ester is 60% by weight or more.

If necessary, a polyfunctional monomer is added to the monomer component for producing the acrylic pressure-sensitive adhesive,
Copolymerized with the above monomer components. The addition of this polyfunctional monomer causes only slight cross-linking between the resulting polymers, which increases the internal cohesive strength of the adhesive. Examples of such a polyfunctional monomer include, but are not limited to, di (meth) acrylate, tri (meth) acrylate, and tetra (meth) acrylate. More specifically, di (meth) acrylate obtained by combining polymethylene glycols such as hexamethylene glycol and octamethylene glycol with (meth) acrylic acid; polyalkylene glycols such as polyethylene glycol and polypropylene glycol Di (meth) acrylate obtained by combining with (meth) acrylic acid; tri (meth) acrylate such as trimethylolpropane tri (meth) acrylate and glycerin tri (meth) acrylate; and pentaerythritol tetra (meth) acrylate. The tetra (meth) acrylate of is exemplified. You may use these polyfunctional monomers in combination of 2 or more types. The polyfunctional monomer is 0.005 with respect to 100 parts by weight of all monomers other than the polyfunctional monomer used for producing the pressure-sensitive adhesive.
Used in a proportion of 0.5 parts by weight. When the amount of the polyfunctional monomer used is less than 0.005 parts by weight, the effect of improving the internal cohesive force by crosslinking is small, and when it exceeds 0.5 parts by weight, the pressure-sensitive adhesive obtained by polymerization easily causes gelation. .

If necessary, a tackifier such as rosin resin, polyterpene resin, coumarone-indene resin, petroleum resin, or terpene-phenol resin may be added to the acrylic pressure-sensitive adhesive.

To prepare an acrylic pressure-sensitive adhesive,
Solution polymerization of the required monomer is carried out in the presence of a polymerization initiator. However, the polymerization form is not limited to this. The polymerization reaction conditions are appropriately selected mainly depending on the kind of the monomer.

In order to form a pressure-sensitive adhesive layer on one side of a substrate, an acrylic pressure-sensitive adhesive solution containing a curing agent and other additives added as necessary is directly applied to one side of the substrate and dried, An adhesive layer having a required thickness is formed. In addition, this solution may be applied onto a process paper and the adhesive layer obtained after drying may be transferred to one side of the substrate. The thickness of the pressure-sensitive adhesive layer varies depending on the purpose of use, but is usually in the range of 20 to 100 μm.

[0020]

The adhesiveness between the acrylic adhesive and rayon is lower than the adhesiveness between the acrylic adhesive and a substance other than rayon, such as pulp or Manila hemp. You can reduce the force required to deploy from.

[0021]

【Example】

Example 1 "DM-3882" (manufactured by Dexter Miki Co., Ltd., basis weight 32 g / m ² , composition: rayon 33) as a nonwoven fabric serving as a base material
%, Pulp 33%, Manila hemp 33%), as an acrylic adhesive "SK Line S-59" (solid content 45
%, Manufactured by Soken Chemical Industry Co., Ltd.) was used. 80 g / m of a mixed liquid prepared by mixing an acrylic pressure-sensitive adhesive with a curing agent "Coronate L55E" (Nippon Polyurethane Co., Ltd.) at a weight ratio of 100: 1 on process paper.
^It was coated with an applicator so as to be ² (dry amount) and dried to form a pressure-sensitive adhesive layer. Then, the pressure-sensitive adhesive layer was brought into close contact with one surface of the substrate, and the process paper was peeled off from the pressure-sensitive adhesive layer to obtain a roll of pressure-sensitive adhesive tape A.

Comparative Example 1 As a non-woven fabric (composition: 17% rayon, 33% pulp,
A rolled body of adhesive tape B was obtained in the same manner as in Example 1 except that Manila hemp 50%) was used.

Comparative Example 2 On the back surface of the non-woven fabric used in Comparative Example 1, a mixed solution of fluororesin emulsion (solid content 35%) and silicone emulsion (solid content 35%) in a weight ratio of 100: 5 was prepared.
A rolled body of adhesive tape C was obtained in the same manner as in Example 1 except that the back-side release-treated nonwoven fabric obtained was applied at 0 g / m ² (dry amount) and then dried. It was

Examples 2 to 5 As shown in Table 2, Examples except that four kinds of non-woven fabrics (basis weight: 30 g / m ² , manufactured by Kokuko Paper Co., Ltd.) having different compositions of rayon and pulp were used. A wound body of an adhesive tape was obtained in the same manner as in 1.

Comparative Example 3 Adhesive tape was wound in the same manner as in Example 1 except that the non-woven fabric "New Soflon M # 300" shown in Table 2 (basis weight: 30 g / m ² , manufactured by Kokuko Paper Co., Ltd.) was used. I got the weight.

Performance test The adhesive tape rolls obtained in the examples and comparative examples were measured for adhesiveness and spreading force. The measurement results are shown in Tables 1 and 2.

[0027]

[Table 1]

[Table 2] Measuring method SP adhesive strength: According to JIS Z0237 "180 degree peeling method".

Development force: According to JIS Z0237 "High-speed unwinding method". However, speed 10m / min, material width 2
It was set to 5 mm.

[0029]

EFFECT OF THE INVENTION Since the pressure-sensitive adhesive tape according to the present invention is constructed as described above, it does not require an extra step such as formation of the release agent layer on the back surface of the substrate, and the adhesive force is lowered due to transfer of the release agent. Therefore, it is possible to reduce the deployment force from the wound body.

Claims (1)

[Claims] 1. A pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is formed on one surface of a non-woven fabric substrate, wherein the pressure-sensitive adhesive layer is formed from an organic solvent solution of an acrylic pressure-sensitive adhesive,
A non-woven fabric containing rayon in a content of 30% by weight or more, which is an adhesive tape.