JP2005170990A - Adhesive tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive tape which is good in adhesion between the substrate that is flame retardant and substantially free of a halogen atom and the layer of an adhesive agent and which has a stable unwinding performance and so can suppress or reduce the generation of the so-called "stick slip phenomenon". <P>SOLUTION: The adhesive tape is the one in which at least one surface of the substrate has an adhesive agent layer. The above substrate contains a polyolefin resin and an inorganic flame retardant and substantially does not contain a halogen atom, and the above adhesive agent layer is composed of an adhesive that contains a water dispersion containing 5-50 pts. wt. of acrylic oligomers (b) to 100 pts. wt. of an acrylic polymer (a). The acrylic polymer (a) is preferably an alkyl (meth)acrylate polymer, and the acrylic oligomers (b) desirably have a weight average mol. wt. of ≥10,000 and ≤100,000. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an adhesive tape using a polyolefin-based resin composition as a base material, and more specifically, no toxic gas such as hydrogen halide such as hydrogen chloride is generated during combustion, and particularly wiring for automobile wires and the like. The present invention relates to a pressure-sensitive adhesive tape useful for binding types (such as various electric wires and cables).

  Conventionally, in a flame-retardant adhesive tape for binding automobile wires, a film made of a resin composition containing a vinyl halide resin such as polyvinyl chloride as a base material has been used. However, since vinyl halide resins generate harmful gases when incinerated, recently, as base materials for adhesive tapes, polyethylene, polypropylene, ethylene-methyl acrylate copolymer (EMA), ethylene-acetic acid are used. Polyolefin resins such as vinyl copolymers (EVA) are beginning to be used as alternative materials for vinyl halide resins.

  Various adhesives are applied to the adhesive tape substrate obtained from such a film to form an adhesive tape. As such an adhesive, a natural rubber adhesive, a synthetic rubber adhesive, an acrylic adhesive, or the like is used (see Patent Documents 1 to 6).

  By the way, when a natural rubber-based pressure-sensitive adhesive is used as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape, the necessary and sufficient heat resistance may not be obtained particularly in applications for binding electric wires for automobiles.

  On the other hand, when an acrylic pressure-sensitive adhesive is used, the heat resistance is superior to that of a natural rubber-based pressure-sensitive adhesive, but it is inferior in adhesiveness to a film mainly composed of a polyolefin-based resin or a wire coating material. Therefore, if a large amount of tackifier is added in order to increase the tackiness, when the adhesive tape is used, the roll-shaped adhesive tape is peeled off (rewinded), and the sound of “billi” is generated. In other words, a so-called “stick slip” phenomenon occurs, which may cause discomfort to the operator. In particular, when performing a winding operation using a large amount of adhesive tape such as bundling of an automobile wire harness, the behavior of the adhesive tape at the time of peeling as described above may be a problem in the work environment.

JP 2000-336328 A JP 2000-336329 A JP-A-9-157615 JP 2001-131509 A JP 2001-192629 A JP 2001-311061 A

Therefore, the object of the present invention is to have good adhesion between the pressure-sensitive adhesive layer and the base material that has flame retardancy and substantially does not contain a halogen atom, and has stable rewinding property, An object of the present invention is to provide an adhesive tape that can suppress or reduce the occurrence of a so-called “stick-slip phenomenon”.
Another object of the present invention is to provide an adhesive tape that has excellent heat resistance, does not generate toxic gas during incineration, and has good winding workability.
Still another object of the present invention is to provide an adhesive tape useful as an adhesive tape for binding wirings.

  As a result of intensive studies to achieve the above object, the present inventors have used a base material made of a specific resin composition as a base material for an adhesive tape, and a specific adhesive composition as an adhesive constituting the adhesive layer. If the product is used, it has flame retardancy, does not generate toxic gas during incineration, has good adhesion between the base material and the pressure-sensitive adhesive layer, and is also sticky from the pressure-sensitive adhesive tape roll. The present inventors have found that the rewindability when rewinding the tape is stable, the so-called “stick-slip phenomenon” does not occur, and the winding workability can be improved, and the present invention has been completed.

  That is, the present invention is an adhesive tape having an adhesive layer on at least one side of a substrate, wherein the substrate contains a polyolefin resin and an inorganic flame retardant and does not substantially contain a halogen atom. The pressure-sensitive adhesive layer is composed of a pressure-sensitive adhesive containing an aqueous dispersion containing 5 to 50 parts by weight of the acrylic oligomer (b) with respect to 100 parts by weight of the acrylic polymer (a). An adhesive tape is provided.

The acrylic polymer (a) is preferably a (meth) acrylic acid alkyl ester polymer. The acrylic oligomer (b) preferably has a weight average molecular weight of 10,000 or more and 100,000 or less. The pressure-sensitive adhesive may further contain 5 to 100 parts by weight of a plasticizer and 5 to 100 parts by weight of a tackifier resin with respect to 100 parts by weight of the acrylic polymer (a). The difference in solubility parameter (SP value) between the acrylic polymer (a) and the acrylic oligomer (b) is preferably 1.0 [(J / cm ³ ) ^1/2 ] or more.

  According to the pressure-sensitive adhesive tape of the present invention, the adhesive property between the base material having flame retardancy and substantially not containing a halogen atom and the pressure-sensitive adhesive layer is good, and has a stable rewinding property. The occurrence of so-called “stick-slip phenomenon” can be suppressed or reduced. That is, the pressure-sensitive adhesive tape of the present invention has excellent heat resistance, does not generate toxic gas during incineration, and has good winding workability. Therefore, the pressure-sensitive adhesive tape of the present invention is useful as a pressure-sensitive adhesive tape for bundling wiring, in particular, as a pressure-sensitive adhesive tape for bundling automobile wire harnesses.

  The pressure-sensitive adhesive tape of the present invention has a pressure-sensitive adhesive layer on at least one side of a base material, and the base material contains a polyolefin resin and an inorganic flame retardant and substantially does not contain a halogen atom. On the other hand, the pressure-sensitive adhesive layer includes a pressure-sensitive adhesive containing an aqueous dispersion containing 5 to 50 parts by weight of the acrylic oligomer (b) with respect to 100 parts by weight of the acrylic polymer (a). It is important that it is configured. Thus, in the present invention, since a specific base material and a specific pressure-sensitive adhesive layer are combined, it has excellent heat resistance and a toxic gas (such as hydrogen halide such as hydrogen chloride) during incineration. ) And the adhesiveness between the substrate and the pressure-sensitive adhesive layer is good. Further, the rewinding property of the adhesive tape from the adhesive tape roll is stable and good, and the occurrence of the so-called “stick-slip phenomenon” is suppressed or reduced.

(Adhesive layer)
As the pressure-sensitive adhesive (pressure-sensitive adhesive) constituting the pressure-sensitive adhesive layer in the pressure-sensitive adhesive tape, an aqueous dispersion containing 5 to 50 parts by weight of the acrylic oligomer (b) with respect to 100 parts by weight of the acrylic polymer (a) A pressure-sensitive adhesive containing (emulsion) is used.

  As the acrylic polymer (a), a (meth) acrylic acid ester polymer having (meth) acrylic acid ester (acrylic acid ester, methacrylic acid ester) as a main monomer component can be used. Examples of such (meth) acrylic acid esters include (meth) acrylic acid alkyl esters shown below, (meth) acrylic acid cycloalkyl esters such as (meth) acrylic acid cyclohexyl, and (meth) acrylic acid phenyl compounds. And (meth) acrylic acid aryl esters.

  As the acrylic polymer (a), in particular, a (meth) acrylic acid alkyl ester polymer having a (meth) acrylic acid alkyl ester as a main monomer component can be suitably used. The (meth) acrylic acid alkyl ester polymer may be a polymer (homopolymer) of only one kind of (meth) acrylic acid alkyl ester, (meth) acrylic acid alkyl ester, and (meth) acrylic. It is a copolymer with other (meth) acrylic acid esters such as acid cycloalkyl esters and (meth) acrylic acid aryl esters, and copolymerizable monomers capable of copolymerizing with (meth) acrylic acid alkyl esters. May be. That is, in the (meth) acrylic acid alkyl ester-based polymer, monomer components such as (meth) acrylic acid alkyl ester may be used singly or in combination of two or more.

Examples of the (meth) acrylic acid alkyl ester in the acrylic polymer (a) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) Butyl acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, Octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate , Undecyl (meth) acrylate, dodecyl (meth) acrylate, ( T) Decyl acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, (meta ) (Meth) acrylic acid C _1-20 alkyl ester [preferably (meth) acrylic acid C _1-14 alkyl ester] such as eicosyl acrylate. As the (meth) acrylic acid alkyl ester, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and octyl (meth) acrylate are particularly preferable. It is.

  In the acrylic polymer (a), examples of the copolymerizable monomer that can be copolymerized with the (meth) acrylic acid alkyl ester include epoxy group-containing acrylic monomers such as glycidyl (meth) acrylate; Carboxyl group-containing monomers such as acrylic acid (acrylic acid, methacrylic acid), itaconic acid, maleic acid, fumaric acid, and crotonic acid; acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; (meth) acrylic acid amino (Meth) acrylic acid aminoalkyl monomers such as ethyl, (meth) acrylic acid N, N-dimethylaminoethyl, (meth) acrylic acid t-butylaminoethyl; (meth) acrylamide, N, N-dimethyl (meth) Acrylamide, N-butyl (meth) acrylamide, N-hydroxy (meta (N-substituted) amide monomers such as acrylamide; vinyl ester monomers such as vinyl acetate and vinyl propionate; styrene monomers such as styrene; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; hydroxy (meth) acrylate Hydroxyl group-containing monomers such as ethyl, hydroxypropyl (meth) acrylate and hydroxybutyl (meth) acrylate; (meth) acrylic acid alkoxyalkyl monomers such as (meth) acrylic acid methoxyethyl and (meth) acrylic acid ethoxyethyl Olefin monomers such as ethylene, propylene, isoprene and butadiene; vinyl ether monomers such as vinyl ether;

  In the acrylic polymer (a), as copolymerizable monomers, hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (Meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy acrylate, polyester acrylate, urethane acrylate, divinylbenzene Polyfunctional monomers such as butyl di (meth) acrylate and hexyl di (meth) acrylate can also be used.

  The acrylic polymer (a) can be prepared by a known or conventional polymerization method. The polymerization method of the acrylic polymer (a) is preferably an emulsion polymerization method from the viewpoint that the pressure-sensitive adhesive composition is finally prepared into an aqueous dispersion, but is not limited thereto, and is not limited to this, and is a solution polymerization method or a block shape. A polymerization method such as a polymerization method may be used. Therefore, the acrylic polymer (a) may be emulsified by using an emulsifier as necessary when polymerizing, and before it is prepared by various polymerization methods and before preparing an aqueous dispersion. The emulsion may be emulsified with an emulsifier, and may be further emulsified with an emulsifier when the aqueous dispersion is prepared after being prepared by various polymerization methods.

  The polymerization initiator, chain transfer agent, emulsifier and the like used in the polymerization of the acrylic polymer (a) are not particularly limited, and can be appropriately selected from known or commonly used ones. More specifically, as the polymerization initiator, for example, an azo polymerization initiator, a peroxide polymerization initiator, a redox polymerization initiator, or the like can be used. Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, and 2,3-dimethylcapto-1-propanol. Examples of the emulsifier include an anionic emulsifier, a nonionic emulsifier, and a radical polymerizable emulsifier.

  It is important that the molecular weight of the acrylic polymer (a) has a weight average molecular weight exceeding 100,000 (for example, more than 100,000 and not more than 10 million). The acrylic polymer (a) preferably has a weight average molecular weight of 300,000 to 5,000,000 (in particular, 500,000 to 2,000,000) from the viewpoint of tackiness and the like.

In the present invention, the weight average molecular weight of the acrylic polymer (a) was measured under the following measurement conditions.
Equipment name: “HLC-8120GPC” manufactured by Tosoh Corporation Column: “G4000 _XL ” + “G2000 _XL ” + “G1000 _XL ” manufactured by Tosoh Corporation Inlet pressure: 6.6 MPa
Column size: 7.8mmφ x 30cm each, total 90cm
Column temperature: 40 ° C
Eluent: Tetrahydrofuran (THF)
Conditions such as flow rate: flow rate 0.8 mL / min, injection volume 100 μL
Detector: Differential refractometer (RI)
Standard sample: Polystyrene (PS)
Data processor: “GPC-8020” manufactured by Tosoh Corporation

  As the acrylic oligomer (b), a (meth) acrylic acid ester oligomer having (meth) acrylic acid ester (acrylic acid ester, methacrylic acid ester) as a main monomer component can be used. Examples of such (meth) acrylic acid esters include (meth) acrylic acid alkyl esters shown below, (meth) acrylic acid cycloalkyl esters such as (meth) acrylic acid cyclohexyl, and (meth) acrylic acid phenyl compounds. And (meth) acrylic acid aryl esters.

  As the acrylic oligomer (b), in particular, a (meth) acrylic acid alkyl ester oligomer having (meth) acrylic acid alkyl ester as a main monomer component can be suitably used. The (meth) acrylic acid alkyl ester-based oligomer may be a polymer (homopolymer) of only one kind of (meth) acrylic acid alkyl ester, other (meth) acrylic acid alkyl esters, In addition to acrylic acid cycloalkyl ester and (meth) acrylic acid aryl ester, it may be a copolymer with a copolymerizable monomer capable of copolymerizing with (meth) acrylic acid alkyl ester. That is, in the (meth) acrylic acid alkyl ester-based oligomer, monomer components such as (meth) acrylic acid alkyl ester may be used alone or in combination of two or more.

In the acrylic oligomer (b), as the (meth) acrylic acid alkyl ester, the same (meth) acrylic acid alkyl ester as the (meth) acrylic acid alkyl ester used in the acrylic polymer (a) [for example, (meth) ) Methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, ( T-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylic acid Isooctyl, (meth) acrylic acid nonyl, (meth) acrylic acid Sononiru, can be used (meth) acrylate, decyl (meth) such as isodecyl acrylate (meth) acrylic acid C _1-20 alkyl ester.

As the (meth) acrylic acid alkyl ester in the acrylic oligomer (b), (meth) acrylic acid C _1-14 alkyl ester is preferable, and in particular, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) Preferred are butyl acrylate, 2-ethylhexyl (meth) acrylate, and octyl (meth) acrylate.

  In the acrylic oligomer (b), the copolymerizable monomer that can be copolymerized with the (meth) acrylic acid alkyl ester is copolymerized with the (meth) acrylic acid alkyl ester in the acrylic polymer (a). A copolymerizable monomer similar to the copolymerizable monomer [for example, an epoxy group-containing acrylic monomer such as glycidyl (meth) acrylate; (meth) acrylic acid (acrylic acid, methacrylic acid), itaconic acid, maleic acid Carboxyl group-containing monomers such as fumaric acid and crotonic acid; acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, (Meth) acrylic acid amino acids such as (meth) acrylic acid t-butylaminoethyl Kill monomers; (N-substituted) amide monomers such as (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-butyl (meth) acrylamide, N-hydroxy (meth) acrylamide; vinyl acetate, propionic acid Vinyl ester monomers such as vinyl; styrene monomers such as styrene; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile, hydroxyl group-containing monomers, alkoxyalkyl monomers (meth) acrylates, olefin monomers, vinyl ethers Monomers, polyfunctional monomers, etc.] can be used.

  The acrylic oligomer (b) can be prepared by a known or conventional polymerization method. As the polymerization method of the acrylic oligomer (b), an emulsion polymerization method is preferable from the viewpoint that the pressure-sensitive adhesive composition is finally prepared into an aqueous dispersion, as in the acrylic polymer (a). However, the polymerization method may be a solution polymerization method or a bulk polymerization method. Therefore, the acrylic oligomer (b) may be emulsified by using an emulsifier as necessary when polymerizing, and before it is prepared by various polymerization methods and before preparing an aqueous dispersion. The emulsion may be emulsified with an emulsifier, and may be further emulsified with an emulsifier when the aqueous dispersion is prepared after being prepared by various polymerization methods.

  The polymerization initiator, chain transfer agent, emulsifier and the like used for the polymerization of the acrylic oligomer (b) are not particularly limited and can be appropriately selected from known or commonly used ones. More specifically, as the polymerization initiator, for example, an azo polymerization initiator, a peroxide polymerization initiator, a redox polymerization initiator, or the like can be used. Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, and 2,3-dimethylcapto-1-propanol. Examples of the emulsifier include an anionic emulsifier, a nonionic emulsifier, and a radical polymerizable emulsifier.

  As for the molecular weight of the acrylic oligomer (b), it is important that the weight average molecular weight is 100,000 or less (for example, 1,000 or more and 100,000 or less). As the acrylic oligomer (b), if the weight average molecular weight is too low, it is easy for the paste to stick out or become sticky. Therefore, the weight average molecular weight is preferably 10,000 or more. Accordingly, the molecular weight of the acrylic oligomer (b) is preferably 10,000 to 100,000 (in particular, 50,000 to 100,000). When the weight average molecular weight of the acrylic oligomer (b) exceeds 100,000, the pressure-sensitive adhesive becomes hard, the adhesiveness between the base material and the pressure-sensitive adhesive layer is reduced, or the pressure-sensitive adhesive tape from the pressure-sensitive adhesive tape roll is removed. The rewinding property is lowered, and further, the so-called “stick-slip phenomenon” easily occurs.

In the present invention, the weight average molecular weight of the acrylic oligomer (b) was measured under the following measurement conditions.
Equipment name: “HLC-8120GPC” manufactured by Tosoh Corporation Column: “G4000 _XL ” + “G2000 _XL ” + “G1000 _XL ” manufactured by Tosoh Corporation Inlet pressure: 6.6 MPa
Column size: 7.8mmφ x 30cm each, total 90cm
Column temperature: 40 ° C
Eluent: Tetrahydrofuran (THF)
Conditions such as flow rate: flow rate 0.8 mL / min, injection volume 100 μL
Detector: Differential refractometer (RI)
Standard sample: Polystyrene (PS)
Data processor: “GPC-8020” manufactured by Tosoh Corporation

  In the aqueous dispersion in the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, the acrylic oligomer (b) is used in a proportion of 5 to 50 parts by weight, preferably 100 parts by weight of the acrylic polymer (a). It is a ratio of 5 to 30 parts by weight (in particular, 5 to 10 parts by weight). When the proportion of the acrylic oligomer (b) is less than 5 parts by weight relative to 100 parts by weight of the acrylic polymer (a), stick slip is likely to occur, and the desired effect may not be obtained. When the amount exceeds the weight part, the acrylic oligomer (b) may bleed out with time, and paste sticking out, adhesive residue, so-called “bamboo shoots”, and terminal peeling may occur.

The acrylic polymer (a) and the acrylic oligomer (b) may have the same composition or different compositions in terms of composition (specifically, the types of monomer components and their composition ratios). Etc. may be the same or different). Therefore, the solubility parameter (SP value; compatibilization parameter) of the acrylic polymer (a) and the SP value of the acrylic oligomer (b) may be the same value or approximate values, and different values. There may be. In the present invention, the acrylic polymer (a) and the acrylic oligomer (b) preferably have a difference in SP value of 1.0 [(J / cm ³ ) ^1/2 ] or more. It is preferable that it is 5 [(J / cm ³ ) ^1/2 ] or more, particularly 2.0 [(J / cm ³ ) ^1/2 ] or more. Thus, when the difference in SP value between the acrylic polymer (a) and the acrylic oligomer (b) is 1.0 [(J / cm ³ ) ^1/2 ] or more, the acrylic polymer (a) And the acrylic oligomer (b) form a microphase-separated structure in the aqueous dispersion, whereby the effects of the present invention are more effectively exhibited. The upper limit of the SP value difference between the acrylic polymer (a) and the acrylic oligomer (b) is not particularly limited, but is, for example, 2.5 [(J / cm ³ ) ^1/2 ] or less, preferably May be 1.5 [(J / cm ³ ) ^1/2 ] or less.

  In addition, as a method for obtaining the SP value, for example, a method of calculating from physical characteristics such as heat of evaporation, refractive index, Kauri-butanol number, surface tension, dipole efficiency, Fedors equation, Small equation, Hoy's equation, etc. Examples include a method of calculating from a chemical composition using a formula, a method of actually measuring from a dissolved state, a cloud point titration method, and the like, and a method using the Fedors formula is particularly preferable. Using the Fedors equation, it can be easily calculated from the chemical structure.

［ΔＥは凝集エネルギー密度、Ｖはモル体積、Δｅ_iは原子又は原子団の蒸発エネルギー、Δｖ_iは原子又は原子団のモル体積である。（但し、ガラス転移温度が２５℃を超える化合物についてはモル体積に次の値を加算する。ｎが３未満の時：加算値（＋Δｖ_i）＝４ｎ、ｎが３以上の時：加算値（＋Δｖ_i）＝２ｎ、ここで、ｎはポリマーの最小繰り返し単位中の主鎖の骨格原子数である）］ Specifically, when the Fedors equation is used, the solubility parameter (SP value) of the acrylic polymer (a) or the acrylic oligomer (b) can be obtained using the following equation (1).

[ΔE is the cohesive energy density, V is the molar volume, Δe _i is the evaporation energy of atoms or atomic groups, and Δv _i is the molar volume of atoms or atomic groups. (However, for a compound having a glass transition temperature of more than 25 ° C., the following value is added to the molar volume. When n is less than 3, added value (+ Δv _i ) = 4 n, when n is 3 or more: added value ( + Δv _i ) = 2n, where n is the number of backbone atoms in the smallest repeating unit of the polymer)]

  The method for obtaining the solubility parameter (SP value) using the above formula (1) is, for example, “basic knowledge of coating” [author: Yuji Harasaki, publisher: Tsuji Shoten, publication date: June 10, 1988] (1 plate, 6 prints), pages 54 to 57].

  The solubility parameter (SP value) of the acrylic polymer (a) and the acrylic oligomer (b) is obtained by past experiments (or calculations) in documents such as “Polymer Handbook” (John Wiley & Sons, Inc.). )) If the value obtained is listed, it may be adopted.

  If the adhesive which comprises an adhesive layer contains the water dispersion which contains 5-50 weight part of acrylic oligomers (b) with respect to 100 weight part of acrylic polymers (a), as needed, And various additives may be included. Examples of such additives include plasticizers (softeners) and tackifier resins, as well as thickeners, crosslinking agents, UV absorbers, antioxidants, fillers, colorants, antistatic agents, and foams. It can be used by appropriately selecting from known additives such as agents and surfactants.

  In such additives, plasticizers include, for example, phthalic acid plasticizers [for example, dibutyl phthalate (DBP), diheptyl phthalate (DHP), dioctyl phthalate (DOP), diisononyl phthalate, diisodecyl phthalate. (DIDP), ditridecyl phthalate (DTDP), ditriisodecyl phthalate, butyl lauryl phthalate, butyl benzyl phthalate, trioctyl trimellitic acid (TOTM), etc.], fatty acid plasticizers [for example, tributyl citrate, dioctyl adipate (DOA) ), Dioctyl azelate (DOZ), dioctyl sebacate (DOS), methyl acetyl lysylate, etc.], phosphate plasticizers [eg tricresyl phosphate (TCP), trioctyl phosphate (TOP), etc.], epoxy Plasticizer And polyester-based plasticizers. Although the compounding quantity of a plasticizer is not restrict | limited in particular, For example, it can select from the range of about 5-100 weight part (preferably 5-20 weight part) with respect to 100 weight part of acrylic polymers (a). If the blending amount of the plasticizer is less than 5 parts by weight relative to 100 parts by weight of the acrylic polymer (a), the desired effect may be deteriorated. On the other hand, if it exceeds 100 parts by weight, adhesive residue or paste sticks out. May cause problems.

  Examples of tackifying resins include rosin derivatives [eg, rosin, polymerized rosin, hydrogenated rosin and derivatives thereof (such as rosin ester resins, hydrogenated rosin ester resins)], terpene resins (eg, terpene resins). , Aromatic modified terpene resins, hydrogenated terpene resins, terpene-phenol resins, etc.), phenolic resins (for example, phenol-formaldehyde resins, alkylphenol-formaldehyde resins, etc.), petroleum hydrocarbon resins [for example, aliphatic petroleum resins , Aromatic petroleum resins, alicyclic petroleum resins hydrogenated with aromatic petroleum resins (alicyclic saturated hydrocarbon resins), etc.], styrene resins, chroman resins (for example, coumarone indene resins, etc.) ) Etc. can be used. Although it does not restrict | limit especially as a compounding quantity of tackifying resin, For example, selecting from the range of about 5-100 weight part (preferably 5-20 weight part) with respect to 100 weight part of acrylic polymers (a). it can. When the compounding amount of the tackifying resin is less than 5 parts by weight with respect to 100 parts by weight of the acrylic polymer (a), the adhesive properties may be deteriorated. On the other hand, when it exceeds 100 parts by weight, the cohesive force of the adhesive As a result, the adhesive may remain on the adherend when it is applied to the adherend and peeled off.

  Furthermore, as for other additives such as a crosslinking agent, known ones can be used, and the blending amount thereof is not particularly limited.

  The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer comprises an acrylic polymer (a), an acrylic oligomer (b), and optionally other additives such as a crosslinking agent in addition to a plasticizer and a tackifier resin. An aqueous dispersion can be prepared and obtained by mixing and emulsifying with an emulsifier if necessary. Of course, when at least one of the acrylic polymer (a) and the acrylic oligomer (b) is already in the form of an aqueous dispersion, the aqueous dispersion Can be prepared. The ratio of the acrylic polymer (a) to the acrylic oligomer (b) is such that the acrylic oligomer (b) is 5 to 50 parts by weight with respect to 100 parts by weight of the acrylic polymer (a). In addition, an adhesive can be used individually or in combination of 2 or more types.

  When preparing an aqueous dispersion by mixing an acrylic polymer (a), an acrylic oligomer (b), and additives such as a plasticizer, a tackifier resin and a crosslinking agent as necessary, a homogenizer, A stirrer such as a disper can be used. When preparing an aqueous dispersion with such a stirrer, for example, a homogeneous dispersion can be obtained by stirring for several minutes at 1,000 rpm to 2,000 rpm.

  In the present invention, it is important to use an aqueous dispersion as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer. Thus, a desired effect can be achieved by using the adhesive in the form of an aqueous dispersion. In addition to the emulsifier used in the preparation of the aqueous dispersion, the emulsifier such as the emulsifier used in the preparation of the acrylic polymer (a) and the acrylic oligomer (b) includes, for example, sodium lauryl sulfate, ammonium lauryl sulfate, and dodecylbenzene. Anionic emulsifiers such as sodium sulfonate, sodium polyoxyethylene alkyl ether sulfate, ammonium polyoxyethylene alkyl phenyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, sodium polyoxyethylene alkyl sulfosuccinate; polyoxyethylene alkyl ether, polyoxy Nonions such as ethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene polyoxypropylene block polymer Emulsifiers and the like. Further, a radical polymerizable emulsifier in which a radical reactive group such as a propenyl group is introduced can also be used. An emulsifier can be used individually or in combination of 2 or more types.

  The pressure-sensitive adhesive layer may have either a single layer or a laminate. The thickness of the pressure-sensitive adhesive layer (thickness after drying) is, for example, about 10 to 50 μm (preferably 15 to 40 μm).

  The pressure-sensitive adhesive layer can be formed by a known or conventional method, and can be formed by using, for example, a casting method, a roll coater method, a reverse coater method, a doctor blade method, or the like.

(Base material)
The base material in the pressure-sensitive adhesive tape of the present invention (sometimes referred to as “pressure-sensitive adhesive tape base material”) contains a polyolefin resin and an inorganic flame retardant, and is made of a plastic material that does not substantially contain a halogen atom. It is configured. Here, “substantially does not contain a halogen atom” means that a substance containing a halogen atom in the molecule is not used as a constituent material of the adhesive tape substrate (plastic film). Therefore, when the composition analysis of the adhesive tape base material is performed by instrumental analysis means, the halogen atom used as a catalyst when synthesizing a halogen atom (for example, a compound (a constituent material of the adhesive tape base material)) detected at a trace level Inclusion of a trace amount of halogen atoms or the like detected from the adhesive tape substrate as a result of mixing of halogen atoms by the substance into the constituent material of the adhesive tape substrate is permitted.

  Examples of polyolefin resins include polyethylene (for example, low density polyethylene, linear low density polyethylene, ultra-low density polyethylene, medium density polyethylene, high density polyethylene, etc.), polypropylene, polybutene, polybutylene, polybutadiene, ethylene- Examples include ethylene such as a propylene copolymer (random copolymer) and / or a copolymer of propylene and another α-olefin (particularly a random copolymer). As the polyolefin resin, polyethylene and polypropylene are preferable, and polyethylene is particularly preferable. Polyolefin resins can be used alone or in combination of two or more.

  The polyolefin resin can be used in combination with other resins. As such a resin, a thermoplastic resin having a carbonyl oxygen atom in the molecular skeleton can be suitably used from the viewpoint of imparting appropriate flexibility to the adhesive tape substrate. As such a thermoplastic resin having a carbonyl oxygen atom (oxygen atom belonging to a carbonyl group) in the molecular skeleton, a soft polyolefin resin having a carbonyl oxygen atom in the molecular skeleton (“carbonyl group-containing polyolefin”). May be referred to as a “system resin”). Of course, since the carbonyl group-containing polyolefin resin is a polyolefin resin, it can be used as a polyolefin resin as a constituent material of the adhesive tape substrate. That is, the carbonyl group-containing polyolefin-based resin may be used alone as a polyolefin-based resin, or may be used together with other polyolefin-based resins.

  Preferable examples of the carbonyl group-containing polyolefin resin include, for example, ethylene, vinyl ester compound and / or α, β-unsaturated carboxylic acid or derivative thereof (anhydride, ester, chloride, etc.) as a monomer component. And an ethylene-based copolymer having a carbonyl group or a metal salt thereof (ionomer). The ethylene copolymer having a carbonyl group or a metal salt thereof (ionomer) generally has a melting point of 120 ° C. or less, preferably 40 to 100 ° C. The melting point can be measured by a differential scanning calorimeter (DSC).

  Examples of the vinyl ester compounds include esters of vinyl alcohols such as vinyl acetate and lower carboxylic acids (vinyl esters of lower carboxylic acids). Examples of the α, β-unsaturated carboxylic acid include (meth) acrylic acid, maleic acid, fumaric acid, and itaconic acid. Examples of α, β-unsaturated carboxylic acid derivatives include α, β-unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride. Examples of the α, β-unsaturated carboxylic acid ester include (meth) acrylic acid ester [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate. , N-butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, Heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, Isodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate (Meth) acrylic acid alkyl ester such as (meth) acrylic acid cyclohexyl ester; (meth) acrylic acid cycloalkyl ester; (meth) acrylic acid aryl ester; (meth) acrylic acid glycidyl, (meth) acrylic acid 2-hydroxy Functional group-containing (meth) acrylic acid esters such as ethyl], maleic acid esters [for example, maleic acid (mono or di) alkyl esters such as monomethyl maleate, monoethyl maleate, diethyl maleate, etc.], fumaric acid esters [ Examples thereof include fumaric acid (mono or di) alkyl esters such as monomethyl fumarate and monoethyl fumarate]. As vinyl ester compounds and / or α, β-unsaturated carboxylic acids or derivatives thereof, vinyl acetate, (meth) acrylic acid, and (meth) acrylic acid esters are preferable, and (meth) acrylic acid esters include (meta ) Acrylic acid alkyl ester [especially ethyl (meth) acrylate, especially ethyl acrylate] is preferred. The vinyl ester compound and / or the α, β-unsaturated carboxylic acid or derivative thereof can be used alone or in combination of two or more.

  Preferable specific examples of the ethylene copolymer having a carbonyl group or a metal salt thereof (ionomer) include, for example, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer, and an ethylene-ethyl acrylate copolymer. , Ethylene-acrylic acid-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-ethyl acrylate copolymer, ethylene-glycidyl methacrylate copolymer, ethylene-glycidyl methacrylate-acrylic acid Examples thereof include ethyl copolymers and their metal salts (ionomers). The ethylene-based copolymer having a carbonyl group or a metal salt (ionomer) thereof can be used alone or in combination of two or more.

  Furthermore, as the polyolefin-based resin, a polymer alloy containing an ethylene component and a propylene component can be used. The configuration (form) of the polymer alloy is not particularly limited. For example, (1) a polymer blend (physical mixture) in which two or more polymers are physically mixed, and (2) two or more types. Block copolymers and graft copolymers in which polymers are covalently bonded, (3) IPN (Interpenetrating Polymer Network) structures in which two or more polymers are intertwined without being covalently bonded to each other, etc. There are various configurations (forms). In addition, the polymer alloy may not necessarily be uniform in composition (may have a distribution), or may be a mixture of two or more polymers (compatible polymer alloy). Those in which the coalescence is incompatible and forms a phase separation structure (incompatible polymer alloy) may be used. Further, it may be one having a heat characteristic having a plurality of exothermic or endothermic peaks as measured by a differential scanning calorimeter (DSC measurement).

  Examples of the polymer alloy containing the ethylene component and the propylene component include a mixture (physical of polypropylene (homopolypropylene, random polypropylene) and polyethylene (including a copolymer of ethylene and a small amount of other α-olefin). Mixture), propylene / ethylene copolymer, terpolymer of propylene, ethylene and other α-olefins other than these (as other α-olefins, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene and the like are preferable, and 1-butene is preferable. The “homopolypropylene” means a polymer (a propylene homopolymer) in which the monomer component is substantially composed only of propylene (consisting of 100%), and “random polypropylene” It means a polypropylene random copolymer in which about several percent of the ethylene component is randomly copolymerized with propylene.

  When the polymer alloy is a copolymer (particularly a block copolymer), the polymer alloy is preferably a copolymer copolymerized by two or more stages of polymerization, and more preferably a propylene / ethylene copolymer. It is. As described in JP-A-4-224809 and JP-A-2001-192629, the copolymer copolymerized by such multistage polymerization is, for example, a catalyst composed of a titanium compound and an organoaluminum compound. In the presence, first, propylene or propylene and another α-olefin are preliminarily polymerized in the first stage of the multistage polymerization, and then polypropylene (a homopolymer of propylene) or propylene-α-olefin copolymer (propylene). And other α-olefin copolymer), and then in the presence of the resin composition obtained in the first stage prepolymerization in the second stage and thereafter, propylene, ethylene and If necessary, it can be prepared by copolymerizing with another α-olefin. As a result, a polymer (polypropylene or propylene-α-olefin copolymer) produced by the first stage prepolymerization and a polymer (propylene-ethylene copolymer or propylene-propylene-polymer produced by the second stage or later copolymerization). A polymer alloy obtained by blending ethylene-other α-olefin copolymer) at the molecular level in the polymerization process in the second and subsequent stages is obtained.

  Examples of the titanium compound include a spherical shape obtained by co-grinding titanium trichloride and magnesium chloride and treating with n-butyl orthotitanate, 2-ethylhexanol, ethyl p-toluate, silicon tetrachloride, diisobutyl phthalate, or the like. Examples thereof include a solid catalyst having an average particle size of 15 μm. In addition, as the organoaluminum compound, for example, an alkylaluminum compound such as triethylaluminum can be used. Further, in the polymerization layer, a silicon compound such as diphenyldimethoxysilane or an iodine compound such as ethyl iodide can be added as an electron donor.

  As such a polymer alloy containing an ethylene component and a propylene component, those exhibiting high elasticity at high temperatures, that is, considering the temperature at the time of use of the adhesive tape, for example, dynamic storage elastic modulus at 80 ° C. ( E ′) is 40 MPa or more and less than 180 MPa (preferably 45 to 160 MPa), and the dynamic storage elastic modulus (E ′) at 120 ° C. is 12 MPa or more and less than 70 MPa (preferably 15 to 65 MPa). . By showing such a dynamic storage elastic modulus (E ′), thermal deformation of the pressure-sensitive adhesive tape substrate (or pressure-sensitive adhesive tape) can be sufficiently suppressed or prevented.

  Specific examples of the polymer alloy having such a dynamic storage elastic modulus (E ′) include, for example, a series of catalloy products (ADFLEX) manufactured by Sun Allomer Co., Ltd. (for example, trade name “KS-353P”, product Name “KS-021P”, product name “C200F”, product name “Q200F”, etc.).

  In addition, as a polymer alloy containing an ethylene component and a propylene component, considering the workability of the adhesive tape near room temperature (such as the adherence of the adhesive tape to the adherend or adherend), the dynamics at 23 ° C. The storage elastic modulus (E ′) is preferably 200 MPa or more and less than 400 MPa. When the polymer alloy has such a dynamic storage elastic modulus (E ′), the pressure-sensitive adhesive tape substrate has good flexibility, and the followability to the adherend or the pressure-sensitive adhesive is improved. .

  As a specific example of the polymer alloy having such a dynamic storage elastic modulus (E ′), as described above, for example, a series of Catalloy products (ADFLEX) manufactured by Sun Allomer Co., Ltd. (for example, a trade name “KS”) -353P ", product name" KS-021P ", product name" C200F ", product name" Q200F ", etc.).

  In addition, the dynamic storage elastic modulus (E ') of a polymer alloy produces the test piece (Thickness 0.2mm, width 10mm, length 20mm) by a polymer alloy, and the dynamic storage elastic modulus by the temperature dispersion | distribution of the said test piece. It is possible to adopt a value obtained by measuring the behavior using a trade name “DMS200 (manufactured by Seiko Instruments Inc.)” as a measuring instrument under the measurement method: tensile mode, heating rate: 2 ° C./min, frequency: 1 Hz. it can.

  The inorganic flame retardant is not particularly limited, and examples thereof include metal hydroxides such as aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, calcium hydroxide, and barium hydroxide; basic magnesium carbonate, magnesium carbonate-calcium, Metal carbonates such as calcium carbonate, barium carbonate and dolomite; metal hydrates such as hydrotalcite and borax (metal compound hydrates); barium metaborate, magnesium oxide, and clay. An inorganic flame retardant can be used individually or in combination of 2 or more types. As the inorganic flame retardant, metal hydroxides such as aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, calcium hydroxide, barium hydroxide, basic magnesium carbonate, and hydrotalcite are preferable. The flame retardant is excellent in the effect of imparting flame retardancy and is economically advantageous.

  The particle size of the inorganic flame retardant varies depending on the type. For example, in the case of a metal hydroxide such as aluminum hydroxide or magnesium hydroxide, the average particle size is 0.1 to 50 μm (preferably 0.5 to 20 μm) is appropriate. The particle diameter (such as average particle diameter) can be measured using a laser diffraction method.

  The inorganic flame retardant may be subjected to a surface treatment. Examples of such surface treatment include silane coupling treatment. In the silane coupling treatment, a known or common silane coupling agent such as an amino silane coupling agent can be used.

  The proportion of the inorganic flame retardant is usually about 20 to 200 parts by weight (preferably 40 to 150 parts by weight) with respect to 100 parts by weight of the polyolefin resin. When the proportion of the inorganic flame retardant is less than 20 parts by weight with respect to 100 parts by weight of the polyolefin resin, the flame retardancy of the adhesive tape base material (or adhesive tape) is lowered, whereas when it is more than 200 parts by weight, The flexibility and extensibility of the adhesive tape substrate (or adhesive tape) are reduced.

  Further, red phosphorus may be used for the purpose of supporting the char (carbonized layer) of the inorganic flame retardant. As the red phosphorus, it is preferable to use one that has been subjected to a technique (a method for stabilizing the surface of red phosphorus) that does not generate toxic phosphine even when heated in the presence of moisture. Specifically, red phosphorus includes a metal hydroxide coating selected from aluminum hydroxide, magnesium hydroxide, zinc hydroxide, and titanium hydroxide, and a coating on the metal hydroxide coating. In addition, it is preferable to provide a coating of a thermosetting resin (such as a phenolic resin) and perform a double coating process.

  The amount of the char-forming aid such as red phosphorus used is not particularly limited. For example, the range is about 2 to 10 parts by weight (preferably 4 to 8 parts by weight) with respect to 100 parts by weight of the polyolefin resin. You can choose from.

  When using a char forming aid such as red phosphorus, it is more preferable to use at least one compound selected from carbon black, borate and silicone compounds (silicone oil, silicone rubber, silicone resin, etc.) in combination. Can be obtained. In this case, the use amount of at least one compound selected from carbon black, borate and silicone compound is, for example, 0.5 to 10 parts by weight (preferably 1 to 5 parts by weight with respect to 100 parts by weight of polyolefin resin). Part) grade.

  For the adhesive tape base material, an inorganic filler (for example, titanium oxide, zinc oxide, etc.), an anti-aging agent (for example, an amine-based anti-aging agent, a quinoline-based anti-aging agent, a hydroquinone-based anti-aging agent, Phenolic antioxidants, phosphorus antioxidants, phosphite ester antioxidants, antioxidants, UV absorbers (eg salicylic acid derivatives, benzophenone UV absorbers, benzotriazole UV absorbers, hindered amines) And other additives such as lubricants, plasticizers, and colorants (eg, pigments, dyes, etc.).

  The method for producing the pressure-sensitive adhesive tape substrate (for example, the method for forming a polyolefin resin film) is not particularly limited. The adhesive tape base is usually a dry blend of a polyolefin resin, an inorganic flame retardant, and various additives such as a filler as required, and the mixture is used with a Banbury mixer, roll, extruder, etc. Kneading (in this case, it can be heated if necessary), and the kneaded product by a known or conventional molding method (for example, compression molding method, calendar molding method, injection molding method, extrusion molding method, etc.) It can be obtained by molding into a film or sheet. As a method for producing the pressure-sensitive adhesive tape substrate, a calendar rolling method or a flat die extrusion method (flat die extrusion method) can be suitably employed.

  The pressure-sensitive adhesive tape substrate has a film-like or sheet-like form. The thickness of the pressure-sensitive adhesive tape substrate (plastic film or sheet) is not particularly limited and is generally about 0.01 to 1 mm (preferably 0.05 to 5 mm), although it varies depending on the application of the pressure-sensitive adhesive tape. In addition, the adhesive tape base material may have a single layer form, and may have a multi-layer form. The adhesive tape base material may be subjected to various treatments such as back treatment, antistatic treatment, and undercoating treatment as necessary.

(Adhesive tape)
The pressure-sensitive adhesive tape of the present invention has a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive containing a specific aqueous dispersion on at least one surface of the pressure-sensitive adhesive tape substrate. Therefore, the pressure-sensitive adhesive tape may have a form in which the pressure-sensitive adhesive layer is formed only on one side of the pressure-sensitive adhesive tape base material, and has a form in which the pressure-sensitive adhesive layer is formed on both sides of the pressure-sensitive adhesive tape base material. Also good. In addition, when the pressure-sensitive adhesive tape has a form in which the pressure-sensitive adhesive layer is formed only on one surface of the pressure-sensitive adhesive tape substrate, the pressure-sensitive adhesive tape is, for example, the pressure-sensitive adhesive tape substrate and one surface of the pressure-sensitive adhesive tape substrate. When the adhesive layer is formed on the other side of the adhesive tape substrate, the adhesive layer is overlapped with the back of the sheet (the surface of the rear treatment layer). By winding it in a roll shape, it can be produced as an adhesive tape in a state or form wound in a roll shape. At this time, the pressure-sensitive adhesive layer is protected by the back treatment layer on the back side of the sheet.

  Of course, when the pressure-sensitive adhesive tape is a double-sided pressure-sensitive adhesive tape or when the back surface of the pressure-sensitive adhesive tape substrate is not a release-treated surface, the pressure-sensitive adhesive layer is protected in a roll shape with a release film (release liner). It is possible to produce an adhesive tape.

  The pressure-sensitive adhesive tape may have other layers (for example, an intermediate layer and an undercoat layer) as long as the effects of the present invention are not impaired.

  As described above, the pressure-sensitive adhesive tape of the present invention has good adhesion between a base material that has flame retardancy and does not substantially contain a halogen atom, and a pressure-sensitive adhesive layer, and has stable rewinding properties. Therefore, the occurrence of the so-called “stick-slip phenomenon” is suppressed or reduced. That is, the pressure-sensitive adhesive tape of the present invention has excellent heat resistance, does not generate toxic gas during incineration, and has good winding workability. Therefore, it can be suitably used as an adhesive tape for binding wiring. The wirings may be any wirings such as various electric wires and cables, and among them, electric wires for electric appliances and electric wires for automobiles (particularly, electric wires for automobiles) are preferably used.

  In the present invention, as the dynamic storage elastic modulus (E ′) of the pressure-sensitive adhesive tape, from the viewpoint of suppressing or preventing thermal deformation, the dynamic storage elastic modulus (E ′) at 80 ° C. is 25 MPa or more and at 120 ° C. The dynamic storage elastic modulus (E ′) is preferably 10 MPa or more. From the viewpoints of flexibility and extensibility, the dynamic storage elastic modulus (E ′) of the pressure-sensitive adhesive tape is such that the dynamic storage elastic modulus (E ′) at 80 ° C. is 200 MPa or less and dynamic storage at 120 ° C. The elastic modulus (E ′) is preferably 150 MPa or less. The dynamic storage elastic modulus (E ′) of the pressure-sensitive adhesive tape is a test piece (width 10 mm, length 20 mm) prepared from a pressure-sensitive adhesive tape provided with a pressure-sensitive adhesive layer on one side of a 0.2 mm-thick pressure-sensitive adhesive tape substrate. Using the trade name “DMS200 (manufactured by Seiko Instruments Inc.)” as a measuring instrument, the dynamic storage elastic modulus behavior due to temperature dispersion of the test piece is measured, measuring method: tensile mode, heating rate: 2 ° C./min, frequency: 1 Hz. Values measured under the measurement conditions can be adopted.

  The dynamic storage elastic modulus (E ′) of the pressure-sensitive adhesive tape is almost the same as the dynamic storage elastic modulus (E ′) of the pressure-sensitive adhesive tape substrate, and is hardly affected by the pressure-sensitive adhesive layer. Therefore, the dynamic storage elastic modulus (E ′) of the adhesive tape is substantially equal to the dynamic storage elastic modulus (E ′) of the adhesive tape substrate. Accordingly, when measuring the dynamic storage elastic modulus (E ′) of the pressure-sensitive adhesive tape, the thickness of the pressure-sensitive adhesive layer is not particularly limited, but may be, for example, 20 μm.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[Preparation Example of Acrylic Polymer (a)]
As monomer components, 2-ethylhexyl acrylate: 92 parts by weight, butyl acrylate: 5 parts by weight, acrylonitrile: 2 parts by weight, methacrylic acid: 1 part by weight (the total weight is 100 parts by weight. Monomer component ”), ammonium lauryl sulfate as an emulsifier (trade name“ Emar AD-25R ”manufactured by Kao Corporation): 2 parts by weight, 2,2′-azobis (2-amidinopropane dihydrochloride) as a polymerization initiator : 0.03 part by weight, and ion-exchanged water: 126.5 parts by weight as a solvent were put into a 1 L flask and emulsified by stirring with a homogenizer for 20 minutes or more. Thereafter, a stirrer, a condenser, a dropping funnel, and a nitrogen introduction tube were attached to the flask, and nitrogen was replaced by flowing nitrogen gas at a flow rate of 10 L / min for 1 hour or more while stirring at a rotation speed of 28 to 32 rpm (average 30 rpm). After nitrogen substitution, the polymerization was started while being immersed in a water bath and controlled so that the temperature of the inner bath was 52 to 56 ° C. (average 54 ° C.), and the polymerization was continued at that temperature for 2 hours or more. Thereafter, separately prepared, 2-ethylhexyl acrylate: 92 parts by weight, butyl acrylate: 5 parts by weight, acrylonitrile: 2 parts by weight, methacrylic acid: 1 part by weight (the total weight is 100 parts by weight. An emulsion comprising 2 parts by weight of ammonium lauryl sulfate (trade name “Emar AD-25R” manufactured by Kao Corporation) as an emulsifier and 0.3 part by weight of ammonium persulfate as a polymerization initiator. In a ratio where the ratio of the monomer component for batch polymerization and the monomer component for drop polymerization is 70/30 (= the monomer component for batch polymerization / the monomer component for drop polymerization), the whole amount is taken from the dropping funnel over about 3 hours. It was dripped using a pump. Thereafter, the temperature of the inner bath is further raised to 75 ° C., polymerization is carried out for about 2 hours, and after completion of the polymerization, 0.4 part by weight of 25% by weight aqueous ammonia solution is added, and (meth) acrylic as an acrylic polymer is added. An aqueous dispersion of an acid alkyl ester polymer (sometimes referred to as “acrylic polymer (A1)”) was obtained.

With respect to this acrylic polymer (A1), the weight average molecular weight was determined by gel permeation chromatography (GPC) to be 127.8 million. In addition, the solubility parameter (SP value) of the acrylic polymer (A1) was 9.6 [(J / cm ³ ) ^1/2 ].

[Preparation example of acrylic oligomer (b)]
As monomer components, n-butyl acrylate: 95 parts by weight, acrylic acid: 5 parts by weight, lauryl mercaptan: 0.8 parts by weight as a chain transfer agent, toluene: 10 parts by weight, 2,2′- as a polymerization initiator Azobisisobutyronitrile: 0.1 part by weight was put into a four-necked flask equipped with a nitrogen introduction tube and a cooling tube, sufficiently substituted with nitrogen, and then stirred at 55 ° C. under a nitrogen stream. Polymerization was carried out for 12 hours to obtain an acrylic oligomer (“acrylic oligomer (B1)”).

The acrylic oligomer (B1) was found to have a weight average molecular weight of 48,000 when determined by gel permeation chromatography (GPC). The solubility parameter (SP value) of the acrylic oligomer (B1) was 8.5 [(J / cm ³ ) ^1/2 ].

  The solubility parameter (SP value) of the acrylic polymer (A1) and the acrylic oligomer (B1) was determined using the Fedors equation represented by the above equation (1). As described above, the method using the Fedors equation is “Basic knowledge of coating” [Author: Yuji Harasaki, Publisher: Tsuji Shoten, Publication date: June 10, 1988 (1 edition, 6 prints), 54-57].

(Example 1)
Acrylic polymer (A1): 100 parts by weight, acrylic oligomer (B1): 20 parts by weight, tackifying resin (trade name “Nanolet R-1050” manufactured by Yasuhara Chemical Co., Ltd.): 20 parts by weight, plasticizer [product Name “Sanso Sizer DIDP” manufactured by Shin Nippon Rika Co., Ltd .; diisodecyl phthalate (DIDP)]: 20 parts by weight, 30 parts by weight of toluene as a thickener, blended at room temperature (20-25 ° C.) with a homomixer The mixture was mixed at a rotational speed of about 1,000 to 2,000 rpm for about 10 minutes to obtain an adhesive composition in an aqueous dispersion. This pressure-sensitive adhesive composition was applied to one side of the following polyolefin-based resin substrate so that the thickness after drying was 25 μm, and a pressure-sensitive adhesive layer was formed to prepare a pressure-sensitive adhesive tape.

  Polyolefin-based resin substrate: trade name “ADFLEX Q-200F” as a polyolefin-based resin [manufactured by Sun Allomer; reactor TPO (olefin-based thermoplastic elastomer); homopolypropylene / ethylene / propylene copolymer = 50/50 (weight) Part)]: 60 parts by weight, ethylene-vinyl acetate copolymer (EVA) (trade name “NIPOFELX635” manufactured by Tosoh Corporation): 40 parts by weight, an aminosilane-treated clay (trade name “TRANSLINK555” manufactured by ENGELHARD Co., Ltd.): 50 parts by weight, phenolic anti-aging agent (trade name “Adekastab AO-60” manufactured by Asahi Denka Kogyo Co., Ltd.): 1.5 parts by weight, phosphorus-based anti-aging agent (trade name “Adekastab HP-10” Asahi Denka Kogyo Co., Ltd.) Company made): 0.2 parts by weight, mono-amide lubricant (quotient) Name “Diamid L-200” manufactured by Nippon Kasei Co., Ltd .: 0.2 parts by weight, nucleating agent (trade name “ADK STAB NA-11” manufactured by Asahi Denka Kogyo Co., Ltd.): 0.3 parts by weight, heavy metal inert Agent (trade name “ADK STAB CDA-1” manufactured by Asahi Denka Kogyo Co., Ltd.): 0.2 parts by weight, pigment (trade name “PE-M6220” Dainichi Seika Kogyo Co., Ltd .; black): 3 parts by weight A polyolefin resin substrate obtained by kneading with a mixing roll and forming a film with a thickness of 80 μm using a calendar.

(Example 2)
Acrylic polymer (A1): 100 parts by weight, acrylic oligomer (B1): 10 parts by weight, tackifier resin (trade name “Nanolet R-1050” manufactured by Yasuhara Chemical Co., Ltd.): 20 parts by weight, plasticizer [product Name “Sanso Sizer DIDP” manufactured by Shin Nippon Rika Co., Ltd .; diisodecyl phthalate (DIDP)]: 20 parts by weight, 30 parts by weight of toluene as a thickener, blended at room temperature (20-25 ° C.) with a homomixer The mixture was mixed at a rotational speed of about 1,000 to 2,000 rpm for about 10 minutes to obtain an adhesive composition in an aqueous dispersion. This pressure-sensitive adhesive composition was applied to one side of a polyolefin-based resin substrate similar to that in Example 1 so that the thickness after drying was 25 μm, and a pressure-sensitive adhesive layer was formed to produce a pressure-sensitive adhesive tape. did.

(Example 3)
Acrylic polymer (A1): 100 parts by weight, acrylic oligomer (B1): 20 parts by weight, tackifier resin (trade name “Superester E-726” manufactured by Arakawa Chemical Industries, Ltd.): 20 parts by weight, softening Agent (plasticizer) [trade name “Sanso Sizer TOTM” manufactured by Shin Nippon Rika Co., Ltd .; trioctyl trimellitic acid (TOTM)]: 20 parts by weight, toluene: 30 parts by weight as a thickener, normal temperature (20 The mixture was mixed for about 10 minutes at a rotational speed of about 1,000 to 2,000 rpm with a homomixer at ˜25 ° C. to obtain an adhesive composition of an aqueous dispersion. This pressure-sensitive adhesive composition was applied to one side of a polyolefin-based resin substrate similar to that in Example 1 so that the thickness after drying was 25 μm, and a pressure-sensitive adhesive layer was formed to produce a pressure-sensitive adhesive tape. did.

(Comparative Example 1)
Acrylic polymer (A1): 100 parts by weight, tackifying resin (trade name “Nanolet R-1050” manufactured by Yasuhara Chemical Co., Ltd.): 20 parts by weight, plasticizer [trade name “Sanso Sizer DIDP” Shin Nippon Rika Co., Ltd. Manufactured; diisodecyl phthalate (DIDP)]: 20 parts by weight, toluene: 30 parts by weight as a thickener, blended at room temperature (20-25 ° C.) with a homomixer and rotated at about 1,000-2,000 rpm The mixture was mixed at a speed for about 10 minutes to obtain an aqueous dispersion pressure-sensitive adhesive composition. This pressure-sensitive adhesive composition was applied to one side of a polyolefin-based resin substrate similar to that in Example 1 so that the thickness after drying was 25 μm, and a pressure-sensitive adhesive layer was formed to produce a pressure-sensitive adhesive tape. did.

(Comparative Example 2)
Acrylic polymer (A1): 100 parts by weight, tackifier resin (trade name “Superester E-726” manufactured by Arakawa Chemical Industries): 20 parts by weight, softener (plasticizer) [trade name “Sanso Sizer "TOTM" manufactured by Shin Nippon Chemical Co., Ltd .; trioctyl trimellitic acid (TOTM)]: 20 parts by weight, toluene: 30 parts by weight as a thickener, and about 1 by using a homomixer at room temperature (20-25 ° C) The mixture was mixed for about 10 minutes at a rotational speed of 2,000 to 2,000 rpm to obtain an adhesive composition of an aqueous dispersion. This pressure-sensitive adhesive composition was applied to one side of a polyolefin-based resin substrate similar to that in Example 1 so that the thickness after drying was 25 μm, and a pressure-sensitive adhesive layer was formed to produce a pressure-sensitive adhesive tape. did.

(Evaluation)
About the adhesive tape obtained in Examples 1-3 and Comparative Examples 1-2, the rewind force, contact tack property, and stick slip property were evaluated with the following measuring method or evaluation method.

(Measurement method of unwinding force)
Using an adhesive tape rewinding tester (device name “rewinding tester” manufactured by Imada Seisakusho Co., Ltd.), rewinding at room temperature (23 ° C.) under the condition of a feeding speed of 30 m / min. N) was measured.

(Evaluation method for contact tackiness)
Compared with the conventional polyvinyl chloride pressure-sensitive adhesive tape (trade name “N.2101S” manufactured by Nitto Denko Corporation; PVC tape), the “tackiness by tactile sensation (tactile tuck)” for the adhesive tape The touch tackiness was evaluated based on the following evaluation criteria.
Evaluation criteria for tactile sensation tack: A tackiness is low and superior to that of a conventional PVC tape.
○: Tackiness is equivalent to that of a conventional PVC tape.
X: Compared with conventional PVC tape, tackiness is high and inferior.

(Evaluation method of stick-slip property)
When the adhesive tape is peeled off at a tensile speed of 30 m / min, it is judged whether it is noisy or not, and a conventional polyvinyl chloride adhesive tape (trade name “N.2101S” manufactured by Nitto Denko Corporation; PVC It was also judged whether there was any sense of incompatibility compared with the tape), and evaluated according to the following evaluation criteria.
Evaluation criteria for stick-slip property ○: No buzzing sound.
×: Buzzing sound

  As is clear from Table 1, the pressure-sensitive adhesive tapes according to Examples 1 to 3 have good rewinding force, excellent tackiness, and further the occurrence of stick-slip phenomenon is suppressed. Therefore, excellent winding workability can be exhibited.

  And since the base material in the adhesive tape which concerns on Examples 1-3 is comprised by the olefin resin, it does not contain a halogen atom and does not generate | occur | produce a harmful gas at the time of incineration. In addition, it contains an inorganic flame retardant and has good heat resistance.

  Furthermore, in the pressure-sensitive adhesive tapes according to Examples 1 to 3, since the water-dispersed acrylic pressure-sensitive adhesive composition containing an acrylic oligomer is used as the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, the acrylic oligomer Compared with the case of using a water-dispersed acrylic pressure-sensitive adhesive composition that does not contain, the adhesion to a base material that does not contain a halogen atom (a base material formed from an olefin resin) is improved.

  Therefore, the adhesive tapes according to Examples 1 to 3 can be suitably used as an adhesive tape for binding wires, and are particularly useful as an adhesive tape for binding electric wires for automobiles that require heat resistance.

Claims (5)

An adhesive tape having an adhesive layer on at least one side of a substrate, wherein the substrate contains a polyolefin resin and an inorganic flame retardant and does not substantially contain a halogen atom, and the adhesive layer is A pressure-sensitive adhesive tape comprising an aqueous dispersion containing an aqueous dispersion containing 5 to 50 parts by weight of an acrylic oligomer (b) with respect to 100 parts by weight of an acrylic polymer (a). The pressure-sensitive adhesive tape according to claim 1, wherein the acrylic polymer (a) is a (meth) acrylic acid alkyl ester polymer. The pressure-sensitive adhesive tape according to claim 1 or 2, wherein the acrylic oligomer (b) has a weight average molecular weight of 10,000 or more and 100,000 or less. The pressure-sensitive adhesive further contains 5 to 100 parts by weight of a plasticizer and 5 to 100 parts by weight of a tackifying resin with respect to 100 parts by weight of the acrylic polymer (a). The adhesive tape as described in the item of. The difference in solubility parameter (SP value) between the acrylic polymer (a) and the acrylic oligomer (b) is 1.0 [(J / cm ³ ) ^1/2 ] or more. The adhesive tape as described in the item.