JP2000038550A - Adhesive tape substrate and adhesive tape - Google Patents

Abstract

(57) [Summary] [Purpose] While taking advantage of the advantages of hot-melt adhesives,
Provided is a pressure-sensitive adhesive tape base material that can significantly suppress adhesive residue on an adherend due to anchorage destruction, and a pressure-sensitive adhesive tape using the pressure-sensitive adhesive tape base material. [Constitution] Polyolefin film forming materials such as polyethylene and polypropylene, and A / B / A type styrene block copolymers such as styrene / ethylene / butylene copolymer / styrene and A such as styrene / ethylene / butylene copolymers / A styrene-based elastomer such as a styrene block polymer is mixed to form a polyolefin layer (polyolefin-based film), and the substrate for an adhesive tape according to the present invention is obtained. Further, a styrene-based hot-melt type pressure-sensitive adhesive layer is laminated on the polyolefin layer of the pressure-sensitive adhesive tape substrate to obtain a pressure-sensitive adhesive tape according to the present invention.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a substrate for an adhesive tape and an adhesive tape. Specifically, the present invention relates to a pressure-sensitive adhesive tape base material excellent in anchoring property with a hot-melt type pressure-sensitive adhesive and a pressure-sensitive adhesive tape using the pressure-sensitive adhesive tape base material.

[0002]

2. Description of the Related Art Since a cellophane adhesive tape using cellophane as a tape base material has been commercially available, an adhesive has been applied to various adhesive tape base materials such as paper, polyvinyl chloride, and polyolefin. It has been used for various purposes. In recent years, its production has been rapidly increasing, and new application fields such as industrial use, medical use as well as consumer use are being developed. At present, the types and uses of pressure-sensitive adhesive tapes that have been put into practical use are specifically listed.
Office / home adhesive tape, bonding adhesive tape, paint masking adhesive tape, surface protection adhesive tape, sealing adhesive tape, anticorrosion / waterproof adhesive tape, electrical insulating adhesive tape, electronic equipment adhesive tape, medical / Adhesive tapes for sanitary materials, adhesive tapes for identification / decoration, adhesive tapes for labels, and other adhesive tapes for specific applications can be cited. Many types of adhesive tapes have been developed and commercialized.

In such a wide range of applications, hot-melt type pressure-sensitive adhesives have attracted attention as adhesives and sealants that can meet demands for energy saving, desolvation, and rationalization of processes in the production of pressure-sensitive adhesive tapes. The development of new hot-melt adhesives and applicators has further expanded the use of adhesive tapes using such adhesives in various fields such as conventional packaging, shoemaking, automobiles, and home appliances.

[0004]

However, in the pressure-sensitive adhesive tape using the hot-melt type pressure-sensitive adhesive, the cohesive force of the pressure-sensitive adhesive decreases due to heating or a change with time, and a part of the pressure-sensitive adhesive is removed when the pressure-sensitive adhesive tape is removed. However, there is a major problem that the adherend is easily contaminated.

[0005] Particularly in relation to the tape base material to be used, the anchoring force between the base material and the polyolefin tape base material is extremely poor, and the problem of the adhesive remaining on the adherend, that is, the so-called adhesive residue has occurred. .

[0006] The present invention has been made in view of the above-mentioned problems of the prior art. By using a hot-melt type pressure-sensitive adhesive, solventless coating can be performed, and it can be manufactured with low energy consumption. To provide a pressure-sensitive adhesive tape base material and a pressure-sensitive adhesive tape using the pressure-sensitive adhesive tape substrate, which can significantly suppress adhesive residue on an adherend due to anchorage destruction while fully utilizing the excellent advantages of the pressure-sensitive adhesive. is there.

The inventors of the present invention have made intensive efforts to solve the above-mentioned problems, and as a result, by blending a styrene-based elastomer with a polyolefin-based film as a base material for an adhesive tape, the anchoring property with a hot-melt-type pressure-sensitive adhesive has been improved. The inventors have found that the present invention is improved, and have completed the present invention.

[0008]

The base material for a pressure-sensitive adhesive tape according to the present invention is a base material for a pressure-sensitive adhesive tape having a polyolefin layer on the lamination surface of a pressure-sensitive adhesive layer, wherein the polyolefin layer is made of a styrene-based elastomer. It is characterized by containing. That is, the adhesive tape substrate according to the present invention,
The purpose of the present invention is to provide a hot-melt type pressure-sensitive adhesive layer with good adhesion to a polyolefin-based pressure-sensitive adhesive tape substrate, and the pressure-sensitive adhesive tape substrate is formed of a polyolefin-based film forming material (hereinafter, referred to as a “polyolefin-based pressure-sensitive adhesive”). A layer-forming material) and a styrene-based elastomer, which is a polyolefin film, that is, a polyolefin layer as defined in the present invention.

The polyolefin layer forming material used in the present invention is an olefin polymer obtained by polymerizing an ethylene hydrocarbon such as ethylene or propylene, such as polyethylene or polypropylene, or a copolymer obtained by copolymerizing the ethylene hydrocarbon. Various olefin copolymers obtained can be used. Specifically, for example, linear or other low-density polyethylene and medium-density polyethylene, high-density polyethylene and ultra-high-molecular-weight polyethylene, in addition to polyolefins composed of a single monomer such as polypropylene, ethylene-propylene copolymer Olefin-based copolymers such as ethylene and propylene-diene copolymers, olefins (meth) acrylate copolymers such as olefin-ethyl acrylate copolymers, and olefins (meth) such as olefin-acrylic acid copolymers An olefin-vinyl copolymer, which is a copolymer of the above-mentioned ethylene hydrocarbon and one or more vinyl monomers such as vinyl chloride, such as an acrylic acid copolymer and an olefin-vinyl acetate copolymer. These polyolefin layer forming materials may be
Species or a mixture of two or more can be used as appropriate. Further, a polymer other than the polyolefin layer-forming material, such as polyester, may be used in combination with the above-mentioned polyolefin layer-forming material.

The styrene-based elastomer used in the present invention improves the adhesion to a hot-melt type pressure-sensitive adhesive, and is not particularly limited as long as it is an elastomer containing styrene as a component. A block copolymer of a polymer of the above-mentioned polyolefin layer-forming material and a styrene polymer is preferably used. Examples of the styrene-based elastomer include styrene / ethylene / butylene copolymer / styrene and styrene / ethylene •
A / B / A type block copolymers such as propylene copolymer / styrene or styrene / butadiene / styrene, styrene / isoprene / styrene, and these A / B /
A / B type such as hydrogenated product of A type block copolymer, styrene / ethylene / butylene copolymer, styrene / ethylene / propylene copolymer or styrene / butadiene copolymer, styrene / isoprene copolymer Examples thereof include block copolymers and hydrogenated products of these A / B type block copolymers. These styrene elastomers can be used alone or as a mixture of two or more.

[0011] These styrene-based elastomers are blended in an appropriate amount with the above-mentioned polyolefin layer-forming material to form a polyolefin layer (polyolefin-based film).
At this time, the styrene elastomer is preferably contained in the polyolefin layer in an amount of 5 to 80% by weight, more preferably 10 to 4% by weight.
It is blended so as to contain 0% by weight. At this time, 5% by weight
If it is less than this, it may not be possible to sufficiently improve the anchoring power. It is desirable that the content of the styrene-based elastomer is as large as possible. However, if the content exceeds 80% by weight, the cost performance is reduced and the cost is increased, and the styrene oxidation may adversely affect the film properties.

In the present invention, the polyolefin layer can be used as a single layer, that is, as a single film, as it is for a substrate for an adhesive tape. In addition, from the viewpoint of improving the strength, heat resistance, and the like of the obtained pressure-sensitive adhesive tape substrate, the pressure-sensitive adhesive tape substrate may be laminated with a substrate layer made of another film. When laminating with another base material layer, a hot-melt adhesive is laminated on the polyolefin layer. The other substrate layer is not particularly limited, and can be appropriately selected depending on the purpose. For example, various films made of the above-mentioned various polyolefin layer forming materials can be mentioned.

Further, the base material for the pressure-sensitive adhesive tape can be obtained by a production method similar to a general film, such as a casting method, a melt molding method or a calender rolling method. Further, in addition to this, an appropriate close contact superposition method such as a recoating method can be used. Among them, from the viewpoint of production efficiency and the like, it is convenient to use an extrusion molding method using a T die, an inflation die, or the like. In particular, in the case of laminating two layers and three layers and a substrate layer, by using coextrusion molding, it is possible to efficiently and easily obtain a pressure-sensitive adhesive tape substrate in which the substrate layers are laminated. In addition, a polyolefin layer and another base material layer may be thermocompression-bonded, a polyolefin layer may be coated with a solution of a forming material for forming another base material layer, or the polyolefin layer may be formed on another base material layer. A base material for a pressure-sensitive adhesive tape having a plurality of layers can be obtained by, for example, repeatedly applying a solution of the material.

The thickness of the base material for the adhesive tape varies depending on the forming material used, the application, and the adhesive used.
In either case of a single polyolefin layer or a case of a plurality of base layers, the thickness is usually 300 μm or less, preferably 150 μm or less, and more preferably 10 to 100 μm or less. When a plurality of base material layers are laminated, the thickness of the polyolefin layer is 30 to 95% of the total thickness, preferably 40 to 85, from the viewpoint of the strength of the base material.
%, Preferably 50 to 80%, and the thickness of the other base material layer is generally 5 to 200 μm, preferably 10 to 100 μm, and more preferably 15 to 85 μm.
It is convenient.

In the adhesive tape substrate of the present invention, if necessary, other additives such as an inorganic filler or a pigment, an antioxidant, an antistatic agent may be added to the polyolefin layer or another substrate layer. Additives, such as an agent, a flame retardant, a lubricant, and a softener, which are used for a usual base material for an adhesive tape, can be blended.

If necessary, the polyolefin layer or the like may be irradiated with radiation such as an electron beam or an ultraviolet ray, or a cross-linking treatment may be performed by mixing a cross-linking agent into each of the above-mentioned base material layers and heating. . By performing the crosslinking treatment in this way,
The strength and heat resistance of the adhesive tape base can be further improved.

The pressure-sensitive adhesive tape according to the present invention is a pressure-sensitive adhesive tape having the above-mentioned pressure-sensitive adhesive tape base material according to the present invention and a hot-melt pressure-sensitive adhesive layer, wherein the hot-melt pressure-sensitive adhesive layer comprises a styrene-based elastomer. It is characterized by being laminated on the polyolefin layer contained. That is, in the pressure-sensitive adhesive tape according to the present invention, a pressure-sensitive adhesive layer made of a hot-melt pressure-sensitive adhesive is laminated on the above-mentioned polyolefin layer.

A styrene-based hot-melt pressure-sensitive adhesive is suitably used for the hot-melt pressure-sensitive adhesive layer. The styrene-based hot melt type pressure-sensitive adhesive is not particularly limited, but a pressure-sensitive adhesive containing one or more of the above-mentioned styrene-based elastomers is preferably used.

The pressure-sensitive adhesive layer may contain, for example, α-pinene, β-pinene polymer, diterpene polymer, α-pinene-phenol copolymer, etc. Suitable hydrocarbon resins such as terpene resins, aliphatic and aromatic resins, aliphatic and aromatic copolymers, rosin resins, coumarone indene resins, (alkyl) phenol resins and xylene resins Tackifiers can be included. Furthermore, softeners such as liquid polymers and paraffinic oils, fillers, pigments, antioxidants, stabilizers,
Various additives such as an ultraviolet absorber necessary according to the use of the pressure-sensitive adhesive tape and the like can be blended.

The pressure-sensitive adhesive layer is laminated on the polyolefin layer of the pressure-sensitive adhesive tape substrate. At this time, the pressure-sensitive adhesive layer is not only laminated on the entire surface of the pressure-sensitive adhesive tape substrate, but also partially depending on the purpose of use or application. Laminating is not a problem. In addition, it is preferable to apply a surface treatment such as a corona treatment, a plasma treatment, or an undercoat treatment to the laminated surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape, as needed, for the purpose of further improving the anchoring force.

Further, in the same manner as in producing a normal hot-melt type pressure-sensitive adhesive tape, a hot-melt coating method by extruding a pressure-sensitive adhesive or a pressure-sensitive adhesive layer formed on another separator (to be peeled off later) may be used. The pressure-sensitive adhesive tape according to the present invention can be obtained by a method of transferring the adhesive tape to a base material for use.

The thickness of the pressure-sensitive adhesive layer may be appropriately set according to the adhesive force, but is generally 1 to 300 μm, preferably 5 to 200 μm, and more preferably 10 to 100 μm.
It is desirable to set to.

[0023]

EXAMPLES Next, various kinds of pressure-sensitive adhesive tapes according to examples of the present invention were produced, and the effects of the present invention were confirmed. (Example 1) By a two-layer coextrusion method via a T die,
Thickness 4 composed of 5% by weight of linear low density polyethylene, 90% by weight of random type polypropylene and 5% by weight of titanium oxide
An adhesive in which a polyolefin layer containing a 10 μm-thick ethylene-based elastomer composed of 96% by weight of random type polypropylene and 4% by weight of styrene / ethylene / butylene copolymer / styrene block copolymer is laminated on a 0 μm base layer. A tape base was obtained.

Next, a 30 μm thick hot melt containing 45% by weight of a styrene / isoprene / styrene block copolymer, 50% by weight of a tackifier resin, and 5% by weight of a petroleum-based oil is formed on the separator by a hot melt coating method. A pressure-sensitive adhesive layer of Example 1 was prepared by forming a mold pressure-sensitive adhesive layer and transferring the pressure-sensitive adhesive layer to the exposed surface of the polyolefin layer of the pressure-sensitive adhesive tape substrate.

Example 2 A polyolefin layer containing a styrene-based elastomer, except that a polyolefin layer composed of 95% by weight of random polypropylene and 5% by weight of a styrene / ethylene / butylene copolymer / styrene block copolymer was used. Is the same as in Example 1.
An adhesive tape of Example 2 was produced.

Example 3 A polyolefin layer containing a styrene-based elastomer and a polyolefin layer composed of 90% by weight of random type polypropylene and 10% by weight of a styrene / ethylene / butylene copolymer / styrene block copolymer was used. Produced the adhesive tape of Example 3 in the same manner as in Example 1.

Example 4 Except for using a polyolefin layer containing 70% by weight of random type polypropylene and 30% by weight of styrene / ethylene / butylene copolymer / styrene block copolymer as a polyolefin layer containing a styrene elastomer. Produced the pressure-sensitive adhesive tape of Example 4 in the same manner as in Example 1.

Example 5 A polyolefin layer containing a styrene-based elastomer and a polyolefin layer composed of 20% by weight of random type polypropylene and 80% by weight of a styrene / ethylene / butylene copolymer / styrene block copolymer was used. Produced the pressure-sensitive adhesive tape of Example 5 in the same manner as in Example 1.

(Example 6) As a polyolefin layer containing a styrene elastomer, except that a polyolefin layer composed of 18% by weight of a random type polypropylene and 82% by weight of a styrene / ethylene / butylene copolymer / styrene block copolymer was used. In the same manner as in Example 1, an adhesive tape of Example 6 was produced.

Comparative Example A two-layer coextrusion method via a T-die was used to form a 40 μm thick base layer composed of 5% by weight of linear low density polyethylene, 90% by weight of random type polypropylene and 5% by weight of titanium oxide. A pressure-sensitive adhesive tape of a comparative example was obtained in the same manner as in Example 1, except that a pressure-sensitive adhesive tape base material having a thickness of 10 μm and consisting of 100% by weight of random type polypropylene was laminated.

[Evaluation Test] Next, the following evaluation tests were conducted using the pressure-sensitive adhesive tapes of Examples 1 to 6 and the pressure-sensitive adhesive tape of Comparative Example. Various adhesive tapes obtained in Examples and Comparative Examples were adhered to a polyester film and a polypropylene film, respectively, as adherends, and the adhesive tape was adhered to each adherend by reciprocating a 2 kgf roller once. Thereafter, the adhesive tape was peeled off by leaving it at room temperature for 1 hour, and the adhesive residue on each adherend was visually observed, and a five-step evaluation was performed according to the following criteria. It was also confirmed whether or not the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape had a fisheye phenomenon. Table 1 shows the results.
Shown in

[Evaluation Criteria] (Glue residue) 1: No glue residue and no stain. 2: There was almost no adhesive residue and dirt was not conspicuous. 3: The adhesive residue was slight, but the stain was not conspicuous. 4: There was adhesive residue, but the stain was not so conspicuous. 5: Glue residue was large and dirt was conspicuous. (Appearance) 1: Fisheye phenomenon was not observed. 2: Fisheye phenomenon was slightly observed. 3: Fisheye phenomenon was observed.

[0033]

[Table 1]

As can be seen from Table 1, in the pressure-sensitive adhesive tapes according to the examples, the adhesive tapes of Examples 1 and 2 showed adhesive residue on the film to be adhered. When the styrene elastomer was blended in an amount of 5% by weight or more, there was no problem in use. In addition, as the amount of the styrene-based elastomer was increased, the adhesive residue was reduced, but the adhesive tape of Example 6 caused a fish-eye phenomenon, and the appearance of the adhesive tape became poor. However, anchor breakage was reduced, and the effect of blending the styrene elastomer was confirmed.

[0035]

The pressure-sensitive adhesive tape substrate according to the present invention is a pressure-sensitive adhesive tape substrate having a polyolefin layer, wherein the polyolefin layer contains a styrene-based elastomer. In particular, the anchoring force with the styrene-based pressure-sensitive adhesive layer can be improved. Therefore, by laminating the styrene-based hot-melt type pressure-sensitive adhesive layer on the polyolefin layer of the pressure-sensitive adhesive tape substrate, it is possible to provide a pressure-sensitive adhesive tape with less adhesive residue on the adherend. Thereby, the application field of the hot-melt adhesive tape is further expanded.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Eiji Yamanaka 1-2-2 Shimohozumi, Ibaraki-shi, Osaka F-term in Nitto Denko Corporation (reference) 4F100 AA21A AK01C AK04B AK04J AK07A AK07B AK09B AK09J AK12B AK12C AK12JAK28C AK63A AL02B AL02C AL05A AL09B BA03 BA07 BA10A BA10C CA04C CA16C EH20 JL13C 4J004 AA07 AB03 CA04 CC02 FA01 FA04 FA05 FA09 FA10

Claims (5)

[Claims] 1. A pressure-sensitive adhesive tape substrate comprising a pressure-sensitive adhesive layer having a polyolefin layer on a laminated surface thereof, wherein the polyolefin layer contains a styrene-based elastomer. 2. The method according to claim 1, wherein the styrenic elastomer is 5-8.
The base material for an adhesive tape according to claim 1, wherein the base material is contained in an amount of 0% by weight. 3. The pressure-sensitive adhesive tape substrate according to claim 1, wherein the pressure-sensitive adhesive tape substrate has a plurality of laminated substrate layers. 4. A pressure-sensitive adhesive tape comprising a pressure-sensitive adhesive tape substrate and a hot-melt pressure-sensitive adhesive layer, wherein the hot-melt pressure-sensitive adhesive is applied to the polyolefin layer of the pressure-sensitive adhesive tape substrate according to claim 1, 2, or 3. A pressure-sensitive adhesive tape, comprising a layer of an agent laminated. 5. The pressure-sensitive adhesive tape according to claim 4, wherein the hot-melt pressure-sensitive adhesive layer contains a styrene-based hot-melt pressure-sensitive adhesive.