JPH08302296A - Base material for tacky tape and tacky tape - Google Patents

Abstract

PURPOSE: To obtain a base material having excellent tacky property and capable of reducing coating amount of a tacky agent without lowering laminate processability by using a composition comprising an olefinic resin and a tackiness-imparting resin as a laminating material on the coating face side of the tacky agent. CONSTITUTION: (A) One face or both faces of a porous base material (e.g. paper, cloth or nonwoven cloth) is laminated with (B) a composition containing a tackiness-imparting resin mainly containing an olefinic resin (preferably a low- density polyethylene or an ethylene-vinyl acetate copolymer, etc., having 1-30g/10min melt flow rate) and a tackiness-imparting resin having <=15 acid value (e.g. a petroleum-based resin or a rosin-base resin) to obtain the objective base material. A laminate-treating face of the base material is coated with a tacky agent to obtain a tacky tape. The containing ratios of the tackiness- imparting resins in the tackiness-imparting resin-containing composition are preferably <=30wt.%, more preferably 5-20wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a pressure-sensitive adhesive tape which uses a porous substrate having a reduced adhesive coating amount and excellent adhesive properties (in the present invention, "adhesive tape" also includes "adhesive sheet"). Regarding).

[0002]

2. Description of the Related Art Conventionally, a porous substrate for an adhesive tape is generally one sided with a cloth, non-woven fabric or paper woven from recycled fibers or synthetic fibers such as sufo-moss, acetate or polyester as a support. What is laminated with a polyolefin resin typified by polyethylene is used. On the opposite side of the laminated surface,
Adhesive is applied.

The adhesive used is generally natural rubber,
Synthetic isoprene rubber or styrene-isoprene-
Styrene copolymer (SIS), styrene-butadiene-
A blend of a tackifier resin and a thermoplastic rubber or a thermoplastic elastomer such as a styrene copolymer (SBS),
So-called rubber adhesives are used. Especially in recent years, S
Hot-melt type solventless adhesives that use thermoplastic elastomers such as IS and SBS have a high adhesive coating speed, do not require solvent drying and recovery, and have no risk of solvent fire. , Has been used frequently for reasons such as improving the working environment and saving resources.

However, these thermoplastic elastomers are expensive. Therefore, in order to reduce the cost, it is desired to reduce the content of the thermoplastic elastomer in the pressure-sensitive adhesive. However, when the content of the elastomer in the pressure-sensitive adhesive is reduced, it is natural that the adhesive and adhesive properties of the pressure-sensitive adhesive tape are reduced. However, there is a problem that it becomes difficult to maintain good. Furthermore, some adhesive thickness is required to maintain good tack and adhesive properties. However, when applying an adhesive to a porous substrate having a large unevenness such as cloth and having a high adhesive penetration, the thickness of the adhesive must be increased unless the coating amount of the adhesive is increased. I can't keep up. In any case, the pressure-sensitive adhesive tape using the pressure-sensitive adhesive made of a thermoplastic elastomer such as SIS or SBS has a problem of high cost.

[0005]

In order to reduce the cost, it is necessary to reduce the penetration of the adhesive into the porous base material. This is because the surface of the porous base material to which the adhesive is applied is reduced. It can be solved by laminating. However, in this case, since the olefin-based resin conventionally used for the laminate resin generally has poor adhesiveness with the pressure-sensitive adhesive, it is peeled off after sticking the pressure-sensitive adhesive tape, and then, between the laminate layer and the pressure-sensitive adhesive layer. Peeling occurs and the adhesive remains on the adherend side, so-called a phenomenon of anchor anchorage failure of the adhesive is likely to occur. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, to reduce the amount of adhesive applied, and to provide an adhesive tape having excellent adhesion and adhesive properties.

[0006]

Means for Solving the Problems The inventors of the present invention have diligently studied for this reason, and as a result, by using a composition comprising an olefin resin and a tackifying resin as a laminating material on the coated surface of an adhesive. The inventors have found that the above object can be achieved without lowering the laminating processability, and have completed the present invention.

That is, according to the present invention, one side or both sides of a porous substrate is laminated with a tackifying resin-containing composition mainly comprising a composition containing an olefin resin and a tackifying resin having an acid value of 15 or less. It is a treated adhesive tape base material, and is an adhesive tape in which an adhesive is applied to the surface of the adhesive tape base material that has been laminated with the tackifying resin-containing composition. Hereinafter, the present invention will be described in detail.

The porous substrate used in the present invention includes:
Examples include paper, cloth, and non-woven fabric. Examples of the paper include kraft paper, crepe paper, Japanese paper, and the like; examples of the cloth include synthetic fibers such as polyester; semi-synthetic fibers such as sufo-moss and acetate; natural fibers such as cotton and hemp.

Examples of the olefin resin used in the present invention include low-density polyethylene, ethylene-vinyl acetate copolymer and modified products thereof, and their melt flow rate (according to JIS K6760, hereinafter referred to as "MFR"). The range of 1 to 30 g / 10 minutes is preferable. MFR
If the value is out of this range, the laminating processability deteriorates, such as the rise in the processing temperature of the resin during lamination and the remarkable neck-in phenomenon.

The low-density polyethylene used is preferably polyethylene having a density of 0.900 to 0.930 g / cm ³ , for example, Nisseki Lexron L501 (MFR: 7).
g / 10 minutes, manufactured by Nippon Petrochemical Co., Ltd., Petrosen 203 (MF)
R: 8g / 10 minutes, manufactured by Tosoh Corporation, Petrosen 204 (MF)
R: 7 g / 10 minutes, manufactured by Tosoh Corporation, Petrosen 205 (MF)
R: 3 g / 10 minutes, manufactured by Tosoh Corporation, Petrosen 212 (MF)
R: 13 g / 10 minutes, manufactured by Tosoh Corporation), Sumikasen L705
(MFR: 7g / 10min, Sumitomo Chemical Co., Ltd.), Yucaron L
M-40 (MFR: 10 g / 10 minutes, manufactured by Mitsubishi Chemical Co., Ltd.), Mirason 10P (MFR: 9.5 g / 10 minutes, manufactured by Mitsui Petrochemical Industry Co., Ltd.) and the like. Examples of the ethylene-vinyl acetate copolymer include Evaflex P1407 (MF
R: 15 g / 10 minutes, manufactured by Mitsui DuPont Polychemical Co., Ltd., Ultrasen 541L (MFR: 9 g / 10 minutes, manufactured by Tosoh Corporation), Sumitate KA-41 (MFR: 9.5 g / 10).
Min., Manufactured by Sumitomo Chemical Co., Ltd.) and the like. The MFR of these low density polyethylenes is preferably 0.5-20.
g / 10 minutes, more preferably 3 to 13 g / 10 minutes. If the MFR is outside this range, the laminating processability is not good.

The tackifying resin used in the present invention includes
Examples thereof include petroleum-based resins, rosin-based resins, terpene-based resins, coumarone-indene resins, and hydrogenated products thereof. Further, these tackifying resins have an acid value of 1
When the acid value exceeds 15, it is necessary to be 5 or less, and gelation of the tackifying resin-containing composition may occur during blending with an olefin resin under heat melting or during laminating, or a laminate film. The pinhole phenomenon of is likely to occur.

The content of the tackifying resin in the tackifying resin-containing composition is preferably 30% by weight or less, more preferably 5 to 20% by weight. If the tackifying resin exceeds 30% by weight, the neck-in phenomenon during laminating becomes large and the laminating processability becomes poor, or the flexibility of the substrate after laminating becomes poor.

The tackifying resin-containing composition used in the present invention may contain, in addition to the above-mentioned olefin resin and tackifying resin, if necessary, within a range not deteriorating the laminate processability and the adhesiveness with the adhesive. A plasticizer, an oil, a filler, an antiaging agent, etc. can be appropriately added. It is also possible to add a pigment to color the laminate layer.

The method for producing the tackifying resin-containing composition is not particularly limited, and for example, it can be produced by kneading and extruding with a kneader and pelletizing with a pelletizer.
The laminating method is also not particularly limited, but the T-die extrusion method is preferable.

The pressure-sensitive adhesive used in the present invention includes, for example, rubber-based, acrylic-based, silicone-based, vinyl ether-based pressure-sensitive adhesives, and usually rubber-based pressure-sensitive adhesives are used.

Rubber-based adhesives include natural rubber, synthetic isoprene rubber, styrene-butadiene rubber, styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene-ethylene-
At least one elastomer component selected from butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, polyisobutylene, butyl rubber, halogenated butyl rubber, chloroprene rubber, acrylonitrile-butadiene rubber, etc. Resin, petroleum-based resin, terpene-based resin, terpene-phenol resin, coumarone-indene resin, styrene-based resin, phenol-based resin, xylene resin or the like is blended with one or more tackifying resins, if necessary, a plasticizer, It is obtained by blending a filler, an antiaging agent and the like.

Usually, 30 to 200 parts by weight of a tackifying resin is added to 100 parts by weight of an elastomer component, and if necessary, a plasticizer, a filler, an antioxidant and the like are added.

[0018]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

Example 1 A tackifying resin-containing composition having the following composition was pelletized using a kneading extruder and a pelletizer. During pelletization, no processing problems such as gelation of resin occurred. Low-density polyethylene (Petrosene 212) 90 parts by weight Aliphatic petroleum resin (TP-001, acid value 0.1, manufactured by Zeon Corporation) 10 parts by weight

Next, using the above resin pellets, a thickness of 1 is obtained.
A Suf-moss woven fabric having 90 μm, 30 weft threads and 40 warp threads was laminated with a T-die so that the laminating amount was 40 g / m ² . There were no problems in laminating such as neck-in phenomenon. Next, on the other side of the woven cloth, M
Low density polyethylene with an FR value of 8g / 10min (Petrosene 2
03) was laminated with a T-die so that the laminating amount was 60 g / m ² , and a release agent composed of a copolymer of 95% by weight of stearyl acrylate and 5% by weight of acrylic acid was further laminated thereon. 0.05 g / m ^{2 was} applied to prepare a base material for an adhesive tape. The total thickness of the substrate after laminating was 230 μm.

Next, a solventless hot melt adhesive having the following composition was prepared by heating, melting and stirring at 190 ° C.
A pressure-sensitive adhesive was applied on the above-mentioned base material tackifying resin-containing composition laminate layer by hot-melting so that the total thickness of the pressure-sensitive adhesive tape was 300 μm to obtain a pressure-sensitive adhesive tape.

Adhesive composition SIS thermoplastic elastomer (Califlex TR1107, Shell Chemical Co., Ltd.) 100 parts by weight Aliphatic petroleum resin (Quinton M100, manufactured by Zeon Corporation) 70 parts by weight Kumaron Inden resin (ESCRON G90, Nippon Steel Chemical Co., Ltd.) 35 parts by weight Naphthenic oil (Shelflex 371N, Shell Chemical Co., Ltd.) 40 parts by weight Bisphenol antioxidant 1 part by weight

The pressure-sensitive adhesive thickness, pressure-sensitive adhesive application amount, pressure-sensitive adhesive strength, and anchorage of the pressure-sensitive adhesive thus obtained were tested according to the following methods. The results are shown in Table 1.

1) Adhesive Thickness Using a dial thickness gauge, the total thickness of the adhesive tape and the thickness of the base material are obtained, and the value obtained by subtracting the thickness of the base material from the total thickness of the adhesive tape is taken as the adhesive thickness. did. 2) Adhesive coating amount The value obtained by subtracting the weight per square meter of the base material from the weight per square meter of the adhesive tape was taken as the adhesive coating amount. 3) Adhesive strength According to JIS Z0237, a 25 mm wide adhesive tape is attached to a stainless steel panel in an atmosphere of 23 ° C., a back and forth pressure is applied once with a 2 kg rubber roll at a speed of 300 mm / min, and after 20 minutes, a peeling speed of 300 mm The adhesive strength was measured by peeling 180 degrees per minute. 4) Anchoring property of pressure-sensitive adhesive An adhesive tape is used as an adherend, and a pressure-sensitive adhesive tape is attached to the rubber roll of 2 kg at a speed of 300 mm / min for one reciprocating pressure-bonding and left in a 50 ° C atmosphere for 3 days, and then in a 23 ° C atmosphere. Left for 1 day,
Rapid peeling at a peeling angle of 180 degrees and a peeling speed of 40 m / min,
The residual property of the adhesive on the glass plate was observed. The case where no residual adhesive was found on the glass plate was rated as ◯, and the case where some residual was caused was rated as x.

Examples 2 and 3 and Comparative Example 1 An adhesive tape was obtained in the same manner as in Example 1 except that the composition of the tackifying resin-containing composition was in accordance with Table 1. Table 1 shows the test results. In Example 2, a hydrogenated rosin ester resin (KE-311, manufactured by Arakawa Chemical Co., Ltd., acid value: 10) was used as the tackifying resin, and in Comparative Example 1, the tackifying resin was not used.

Comparative Example 2 Phenol-modified rosin having an acid value of 18 (Tamanor 135, manufactured by Arakawa Chemical Co., Ltd.) was used as a tackifying resin, and kneaded and extruded into pellets in the same manner as in Example 1 in accordance with the composition shown in Table 1. The obtained tackifying resin-containing composition turned dark brown. Then, using this pellet, T
I tried extrusion lamination with a die, but a large number of holes were generated in the extruded film, a uniform film could not be obtained,
It could not be laminated.

Comparative Example 3 The adhesive coated surface side was not laminated, and the opposite surface side was made of low density polyethylene (Petrosene 2) as in Example 1.
03) was laminated so that the amount of lamination was 70 g / m ² , and treated with a release agent in the same manner as in Example 1 to prepare a base material for an adhesive tape. Then, the pressure-sensitive adhesive used in Example 1 was applied to the surface not laminated to give a total thickness of 30.
Hot-melt coating was applied so that the thickness became 0 μm to obtain an adhesive tape. Table 1 shows the test results.

Comparative Example 4 A base material was prepared in the same manner as in Comparative Example 3, and the pressure-sensitive adhesive used in Example 1 was applied in the same manner as in Example 1 so that the adhesive coating amount was 100 g / m ^2. A tape was prepared. The total thickness of the resulting tape was 250 μm. Table 1 shows the test results.

[0029]

[Table 1]

[0030]

EFFECTS OF THE INVENTION The pressure-sensitive adhesive tapes obtained in Examples 1 to 3 of the present invention have the same pressure-sensitive adhesive as the conventional cloth pressure-sensitive adhesive tape, even though the amount of pressure-sensitive adhesive applied is 70 g / m ² less. The thickness can be maintained, the adhesive strength is the same, and there is no problem with the anchoring property of the adhesive. In Comparative Example 1, the tackifying resin was not added to the laminate resin, but the anchoring property of the pressure sensitive adhesive was insufficient. In Comparative Example 2, the tackifying resin had a large acid value and could not be laminated. In Comparative Example 3, the cloth adhesive tape is produced by the conventional method, but the amount of the adhesive applied must be large and the cost is high. Further, Comparative Example 4 has the same adhesive coating amount as that required in Example 1 on the substrate prepared by the conventional method,
This is a prepared adhesive tape, and its adhesive properties are extremely inferior.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hiroki Matsushita 2-3-3 Sekiguchi, Bunkyo-ku, Tokyo Nichiban Co., Ltd.

Claims (2)

[Claims] 1. A pressure-sensitive adhesive tape obtained by laminating one or both surfaces of a porous substrate with a tackifying resin-containing composition mainly containing a composition containing an olefin resin and a tackifying resin having an acid value of 15 or less. Substrate. 2. An adhesive tape in which an adhesive is applied to the laminated surface of the adhesive tape substrate of claim 1.