JP6676461B2 - Adhesive tape - Google Patents

Description

  The present invention relates to an adhesive tape.

  To temporarily protect the surface of a metal plate, an adhesive tape is used (for example, Patent Document 1). This kind of adhesive tape is attached so as to cover the surface of the metal plate so as not to damage the metal plate when processing or storing the metal plate. Then, the adhesive tape is finally peeled off from the metal plate.

  In such a pressure-sensitive adhesive tape, a polyvinyl chloride (PVC) film to which a plasticizer is added is used as a base material for supporting a pressure-sensitive adhesive layer, for reasons such as excellent flexibility. As the plasticizer, for example, bis (n-octyl) phthalate (hereinafter, DOP) is used. DOP is easy to handle because it is liquid in a wide temperature range including room temperature, and has high compatibility with PVC. Therefore, DOP has been frequently used as a plasticizer of this kind.

JP 2015-20405 A

  By the way, regulations for managing the use of chemical substances in Europe (Registration, Evaluation, Authorization and Restriction of Chemicals, hereinafter referred to as REACH regulations) are going to restrict the use of DOP for the purpose of reducing environmental load. Therefore, the use of other plasticizers in place of DOP is being studied. As an alternative to DOP, for example, bis (2-ethylhexyl) terephthalate (hereinafter, DOTP) can be given.

  However, when DOTP is used as a plasticizer, when the adhesive tape is peeled off from the adherend, dirt sometimes adheres to the surface of the adherend. It is considered that this contamination occurs because some substance moves to the adhesive tape side or the adherend side when the adhesive tape is attached to the adherend. Note that this stain is not seen when DOP is used as a plasticizer, but is seen when a substitute for DOP (for example, DOTP) is used.

  An object of the present invention is to provide an adhesive tape in which contamination on the surface of an adherend is suppressed.

  The present inventors have conducted intensive studies to achieve the object, and as a result, comprising a polyvinyl chloride-based substrate and a rubber-based pressure-sensitive adhesive layer formed on at least one surface of the polyvinyl chloride-based substrate, The polyvinyl chloride-based substrate and the rubber-based pressure-sensitive adhesive layer contain a benzenedicarboxylic acid ester represented by the following general formula (1) as a plasticizer, and the rubber-based pressure-sensitive adhesive layer is formed of an alkylphenol-based aggregate. The present inventors have found that the pressure-sensitive adhesive tape containing a modifier can suppress the contamination of the adherend surface, and have completed the present invention.

（式中、ベンゼン核の２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）がオルト位の場合、Ｒ^１及びＲ^２は炭素数が９以上でありかつ少なくとも１つの第三級炭素原子を含む分岐アルキル基からなり、ベンゼン核の２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）がメタ位又はパラ位の場合、炭素数が８以上でありかつ少なくとも１つの第三級炭素原子を含む分岐アルキル基からなる。なお、２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）は、同一又は互いに異なってもよい。）

(Wherein, when _two substituents (—CO ₂ R ¹ , —CO ₂ R ² ) of the benzene nucleus are in the ortho position, R ¹ and R ² have 9 or more carbon atoms and at least one tertiary group. It is composed of a branched alkyl group containing a carbon atom, and when two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) of the benzene nucleus are in the meta or para position, the number of carbon atoms is 8 or more and at least one It comprises a branched alkyl group containing a tertiary carbon atom.The _two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) may be the same or different.)

  In the pressure-sensitive adhesive tape, the alkylphenols preferably have an acid value of 11 to 150.

  In the pressure-sensitive adhesive tape, it is preferable that the benzenedicarboxylic acid ester is contained in the pressure-sensitive adhesive tape in an amount of 10% by mass or more and 50% by mass or less.

  In the pressure-sensitive adhesive tape, the ratio (mass ratio) of the alkylphenols to the benzenedicarboxylic acid ester contained in the pressure-sensitive adhesive tape is preferably 0.0005 or more and 0.1 or less.

  In the pressure-sensitive adhesive tape, a ratio (ta / tb) of a thickness ta of the polyvinyl chloride base material to a thickness tb of the rubber-based pressure-sensitive adhesive layer is preferably 5 or more and 15 or less.

  In the pressure-sensitive adhesive tape, it is preferable that the thickness ta of the polyvinyl chloride base material is 90 μm or more and 110 μm or less.

  In the pressure-sensitive adhesive tape, it is preferable that a maximum elongation of the polyvinyl chloride base material measured according to JIS-K-7127 is 100% or more.

  In the pressure-sensitive adhesive tape, the alkyl moiety of the alkylphenol may be at least one selected from the group consisting of isoprene, hydrogenated isoprene, and isoprene derivatives.

  In the pressure-sensitive adhesive tape, the isoprene derivative may be at least one selected from the group consisting of terpenes, rosin acids, terpene derivatives, and rosin acid derivatives.

  The adhesive tape may be used for processing a metal plate.

  ADVANTAGE OF THE INVENTION According to this invention, the adhesive tape which the contamination of the adherend surface was suppressed can be provided.

Explanatory diagram schematically showing an example of an adhesive tape Explanatory drawing schematically showing another example of the adhesive tape

〔Adhesive tape〕
The pressure-sensitive adhesive tape according to the present embodiment includes a polyvinyl chloride-based substrate and a rubber-based pressure-sensitive adhesive layer formed on at least one surface of the polyvinyl chloride-based substrate.

  FIG. 1 is an explanatory diagram schematically illustrating an example of the adhesive tape 10. As shown in FIG. 1, the pressure-sensitive adhesive tape 10 includes a polyvinyl chloride-based substrate 11 and a rubber-based pressure-sensitive adhesive layer 12.

  In general, the “adhesive tape” may be called with a different name from “adhesive sheet”, “adhesive film”, and the like, but in the present specification, the expression is unified to “adhesive tape”. Further, the surface of the rubber-based pressure-sensitive adhesive layer in the pressure-sensitive adhesive tape may be referred to as a “pressure-sensitive adhesive surface”.

(Polyvinyl chloride base material)
A polyvinyl chloride-based substrate (hereinafter, sometimes referred to as a “PVC-based substrate”) is a substrate containing polyvinyl chloride as a main component, and contains benzenedicarboxylate as a plasticizer. The PVC base material may have a single-layer structure or a laminated (multi-layer) structure.

  The content ratio of polyvinyl chloride in the PVC-based substrate is not particularly limited, but is, for example, preferably 60% by mass or more, more preferably 65% by mass or more based on the total mass (100% by mass) of the PVC-based substrate. , 70% by mass or more is more preferable. The upper limit of the polyvinyl chloride content is not particularly limited, but is, for example, preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less. When the content ratio of polyvinyl chloride in the PVC base material is in such a range, the rigidity of the PVC base material is ensured, and the stress relaxation property of the PVC base material is excellent. Further, when the content ratio of polyvinyl chloride in the PVC base material is within such a range, a plasticizer or the like can be added to the PVC base material, and the softness and solvent resistance of the base material can be improved. And other properties can be adjusted.

  As the polyvinyl chloride, soft polyvinyl chloride (for example, polyvinyl chloride having a degree of polymerization of 1500 or less) is preferable. The degree of polymerization (average degree of polymerization) of the polyvinyl chloride is not particularly limited, but is preferably, for example, 500 to 1300, and more preferably 900 to 1300. When the degree of polymerization is in the above range, the flexibility of the PVC-based substrate is ensured. The degree of polymerization of polyvinyl chloride can be adjusted by, for example, the content of vinyl chloride at the time of polymerization.

  In the present specification, the degree of polymerization refers to a degree measured in accordance with JIS K 6721 (1977). Specifically, for example, it can be measured by the following method for measuring the average degree of polymerization.

[Method of measuring average degree of polymerization]
Using polyvinyl chloride to be measured as a sample, 200 ± 1 mg of the sample dried in a desiccator at room temperature in advance is weighed, transferred to a volumetric flask, added with about 40 ml of nitrobenzene, and heated to about 100 ° C. When the sample is apparently completely dissolved, it is cooled, and nitrobenzene is further added to make a total volume of 50 ml at 30 ± 0.05 ° C., which is used as a test solution. Using the test liquid, relative viscosity (η _re1 ) and specific viscosity (η _sp ) are measured by an _Ubbelohde viscometer. Then, the intrinsic viscosity ([η]) is obtained by the following equation (1), and the average degree of polymerization (P) is calculated by the following equation (2).
[Η] = (√2 / C ) × √ (η sp -log e η re1) ····· (1)
P = 500 × {antilog ₁₀ ([η] /0.168) -1} (2)
C: concentration of test solution (g / l)

  The PVC-based substrate may contain a resin other than polyvinyl chloride as long as the object of the present invention is not impaired. Examples of the resin other than the polyvinyl chloride include polyolefin, polyester, polyimide, and polyamide. The other resin may be used alone or in combination of two or more. The content ratio of the resin other than the polyvinyl chloride is not particularly limited, but is preferably, for example, 1.0 to 10.0% by mass relative to the total mass (100% by mass) of the PVC base material. Preferably it is 1.0-5.0 mass%.

(Plasticizer)
The PVC base material contains a benzenedicarboxylic acid ester represented by the following general formula (1) as a plasticizer.

（式中、ベンゼン核の２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）がオルト位の場合、Ｒ^１及びＲ^２は炭素数が９以上でありかつ少なくとも１つの第三級炭素原子を含む分岐アルキル基からなり、ベンゼン核の２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）がメタ位又はパラ位の場合、炭素数が８以上でありかつ少なくとも１つの第三級炭素原子を含む分岐アルキル基からなる。また、２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）は、同一又は互いに異なってもよい。）

(Wherein, when _two substituents (—CO ₂ R ¹ , —CO ₂ R ² ) of the benzene nucleus are in the ortho position, R ¹ and R ² have 9 or more carbon atoms and at least one tertiary group. It is composed of a branched alkyl group containing a carbon atom, and when two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) of the benzene nucleus are in the meta or para position, the number of carbon atoms is 8 or more and at least one It consists of a branched alkyl group containing a tertiary carbon atom, and the two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) may be the same or different from each other.)

  By containing such a plasticizer, the PVC base material can have appropriate flexibility (plasticity), stretchability, and the like.

Such a benzenedicarboxylic acid ester is hardly volatile, and it is easy to reduce the environmental load. Further, since the benzenedicarboxylic acid ester contains a tertiary carbon atom in the alkyl group (that is, has a branched alkyl group (R ¹ , R ² )), it hardly aggregates and hardens or crystallizes. For example, it is easy to stabilize the tape characteristics at 0 ° C).

  Examples of the benzenedicarboxylate include dialkyl phthalate, dialkyl isophthalate, and dialkyl terephthalate.

The upper limit of the number of carbon atoms of the branched alkyl group (R ¹ , R ² ) is preferably 14 or less, more preferably 13 or less, and even more preferably 10 or less.

Particularly, when the branched alkyl group (R ¹ , R ² ) of the benzenedicarboxylic acid ester is a 2-ethylhexyl group or an isononyl group, the number of carbon atoms thereof is the same as the number of carbon atoms of the alkyl group (2-ethylhexyl group) of DOP. Or, because of one difference, the chemistry is very close to DOP and is suitable as a replacement for DOP.

  Preferred benzenedicarboxylic acid esters include, for example, diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), di- (2-ethylhexyl) terephthalate (DOTP, bis (2-ethylhexyl) terephthalate), diisononyl terephthalate, And diisodecyl terephthalate.

  More preferred benzene dicarboxylic acid esters include dialkyl terephthalate in which two substituents in the benzene nucleus in the general formula (1) are located at the para position (for example, di- (2-ethylhexyl) terephthalate, diisononyl terephthalate, terephthalate) Diisodecyl acid). These are particularly preferable because they have high molecular symmetry and increase the intermolecular interaction, thereby lowering the volatility and reducing the burden on the environment.

  The blending amount of the plasticizer in the PVC-based substrate is appropriately set according to the purpose. The amount of such a plasticizer is preferably at least 10 parts by mass, more preferably at least 15 parts by mass, preferably at most 50 parts by mass, more preferably at most 45 parts by mass, based on 100 parts by mass of the resin component. It is. When the amount of the plasticizer is in such a range, the flexibility of the pressure-sensitive adhesive tape is ensured, the workability such as bonding of the pressure-sensitive adhesive tape is improved, and the followability to the adherend is ensured. Further, when the content ratio (mass%) of the plasticizer is in such a range, the plasticizer is prevented from seeping out of the PVC base material or the like, and the workability such as bonding and the adhesive strength are secured.

  Stabilizers, colorants, antistatic agents, ultraviolet absorbers, and the like may be added to the PVC-based substrate as long as the object of the present invention is not impaired.

  The thickness ta of the PVC-based substrate is not particularly limited and is appropriately set according to the purpose. For example, the lower limit of the thickness of the PVC base material is preferably 20 μm or more, more preferably 40 μm or more, and still more preferably 50 μm or more. In addition, for example, the upper limit of the thickness of the PVC base material is preferably 200 μm or less, more preferably 150 μm or less, and further preferably 130 μm or less. When the thickness of the PVC-based material is in such a range, the handleability is excellent, and the stretchability, flexibility, and followability of the PVC-based material are excellent.

  The maximum elongation (%) of the PVC base material measured according to JIS K 7127 is not particularly limited, but is, for example, preferably 100% or more, and more preferably 200% or more. The upper limit of the maximum elongation (%) is not particularly limited, but is preferably, for example, about 1000%. When the maximum elongation (%) of the PVC-based substrate is in such a range, appropriate elongation is ensured for the PVC-based substrate, and the followability of the rubber-based pressure-sensitive adhesive tape to an adherend is improved.

  The surface of the PVC-based substrate may be subjected to, for example, a surface treatment as necessary. Examples of the surface treatment include, but are not particularly limited to, for example, corona discharge treatment, plasma treatment, sand matting treatment, ozone exposure, flame exposure, high piezoelectric shock exposure, physical treatment such as ionizing radiation treatment, and chemical treatment such as chromic acid treatment. Treatment, coating treatment (coating treatment) with a coating agent (formation of an undercoat layer), and the like.

  The method for producing the PVC-based substrate is not particularly limited, and is, for example, a known film (sheet) molding method such as injection molding, extrusion molding (T-die extrusion molding, etc.), inflation molding, calendar molding, blow molding, casting molding, and the like. Is mentioned.

(Rubber adhesive layer)
The rubber-based pressure-sensitive adhesive layer is formed on a layer of a rubber-based pressure-sensitive adhesive containing a rubber component (rubber-based polymer) as a main component, and is formed on at least one surface of a PVC-based substrate. The rubber-based pressure-sensitive adhesive layer contains, as described later, a cohesion modifier composed of alkylphenols as an essential component.

  The content ratio (% by mass) (lower limit) of the rubber component in the rubber-based pressure-sensitive adhesive layer is 50% by mass or more, preferably 55% by mass or more, and more preferably 60% by mass or more. The upper limit of the content ratio (% by mass) is, for example, 95% by mass or less, preferably 90% by mass or less, and more preferably 85% by mass or less. When the content ratio (mass%) of the rubber component in the rubber-based pressure-sensitive adhesive layer is within such a range, the necessary adhesive strength of the pressure-sensitive adhesive tape is ensured.

  Examples of the rubber component include, but are not particularly limited to, natural rubber; modified natural rubber; styrene-butadiene-styrene block copolymer, styrene-butadiene rubber, styrene-isoprene-styrene block copolymer (SIS), Styrene-ethylene / butylene-styrene block copolymer, isoprene rubber, polybutadiene rubber, ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, polyisobutylene rubber, butyl rubber, chloroprene rubber Synthetic rubber such as rubber and the like are included. These may be used alone or in combination of two or more. In the present specification, the natural rubber and the modified natural rubber may be referred to as “natural rubber-based components”.

  The synthetic rubber may be unmodified or modified (for example, carboxyl-modified chloroprene rubber). In the present specification, the synthetic rubber (unmodified) and the modified synthetic rubber may be referred to as “synthetic rubber-based components”.

  The modified natural rubber comprises a structure derived from natural rubber in an amount of 50% by mass or more (preferably 60% by mass or more). Examples of the modified transformed rubber include, for example, a graft-modified natural rubber obtained by graft-polymerizing a monomer (for example, an acrylate) to a natural rubber. As the monomer to be graft-polymerized to the natural rubber, one or two or more monomers that can be graft-polymerized to the natural rubber such as acrylic monomers and styrene are used.

  As the modified natural rubber, an acrylic modified natural rubber in which 50% by mass or more of the monomer to be graft-polymerized to the natural rubber is an acrylic monomer is preferable.

  In the acrylic-modified natural rubber, as the acrylic monomer to be graft-polymerized to the natural rubber, a (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 1 to 16 carbon atoms (for example, methyl acrylate, Ethyl acrylate, isopropyl acrylate, tert-butyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, tert-butyl methacrylate), acrylic acid, methacrylic acid, and the like. These may be used alone or in combination of two or more.

  As the acrylic monomer to be graft-polymerized to natural rubber, methyl methacrylate (MMA) is preferable.

  The method of graft-polymerizing an acrylic monomer or the like to natural rubber is not particularly limited, and a known polymerization method is used.

(Aggregation modifier)
The aggregation modifier has a function of suppressing aggregation of the plasticizer used in place of DOP in the rubber-based pressure-sensitive adhesive layer. When the plasticizer agglomerates in the rubber-based pressure-sensitive adhesive layer, the plasticizer solidifies or crystallizes, which eventually causes a contaminant to adhere to the adherend. Therefore, the rubber-based pressure-sensitive adhesive layer contains a cohesion modifier to suppress coagulation of the plasticizer.

  The aggregation modifier consists of alkylphenols. Alkyl phenols have an alkyl moiety and a phenol moiety. Alkyl phenols increase the compatibility between the rubber-based adhesive and the plasticizer by showing that the alkyl moiety has an affinity for the rubber-based adhesive and the hydroxyl group contained in the phenol moiety has an affinity for the plasticizer. It is presumed.

  Specific examples of the alkyl moiety included in the alkylphenol include a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group, an n-pentyl group, an n- (3-oxa) pentyl group, an n-hexyl group, Examples thereof include linear alkyl groups such as n- (3-aza) heptyl group, n-heptyl group, and n-octyl group. Further, a branched alkyl group in which a functional group such as an alkyl substituent is bonded to the linear alkyl group has advantages such as easy mixing with a tape constituting material, and is preferable.

  Examples of the branched alkyl group include isoprene, hydrogenated isoprene obtained by hydrogenating isoprene, isoprene, and an isoprene derivative obtained by multiplying isoprene or a hydrogenated isoprene. These are particularly preferable because they can be obtained from natural extracts and can be expected to further reduce the environmental load.

  Specific isoprene derivatives include, for example, pinene, limonene, myrcene, camphene, dipentene, rosin, rosin acid and the like.

  It should be noted that the isoprene derivative may be produced not only from a natural extract but also from isoprene or a hydrogenated isoprene produced by a known method. The method for producing the isoprene derivative is described, for example, in the document "Synthetic Organic Chemistry, Vol. 24, No. 11, 1028-1040, 1966".

  Examples of the phenol moiety of the alkylphenols include phenol analogs such as phenolic hydroxyl group-containing polycyclic aromatics such as phenol and naphthol, and phenol derivatives having a plurality of phenolic hydroxyl groups such as resorcinol. This is because the electron of the oxygen atom in the hydroxyl group resonates with the aromatic ring, which is the same from the viewpoint of obtaining the above-mentioned affinity.

  Examples of commercially available products that can be used as alkylphenols include, for example, trade names “YS resins” (manufactured by Yasuhara Chemical Co., Ltd.), trade names “Tamanols” (manufactured by Arakawa Chemical Industries, Ltd.), and trade names “Sumilite Resin PRs” And the like.

  Alkyl phenols can be obtained by a known organic synthesis method such as a Friedel-Crafts reaction described in the above literature or a coupling reaction between a precursor of the alkyl group and a precursor of the phenol analog using a Pd catalyst or the like. It is possible to get.

  Further, a product obtained by polymerizing (resinifying) an alkylphenol using the above reaction has, for example, a glass transition temperature (Tg). It is particularly preferable as an aggregation modifier because the property can be changed.

  Further, the acid value of the alkylphenols is preferably from 11 to 150, more preferably from 13 to 125, and still more preferably from 15 to 110. When the acid value of the alkylphenols is in such a range, the effect of suppressing aggregation of the plasticizer can be exerted, and the adhesive property of the rubber-based pressure-sensitive adhesive layer is altered, and the adherend is a metal. In such a case, there is no risk of corroding the adherend.

  The aggregation modifier may be used alone or in combination of two or more.

  The aggregation modifier is added to the rubber-based pressure-sensitive adhesive layer so as to be contained in a mass ratio of 10 to 200% with respect to the plasticizer in the pressure-sensitive adhesive tape. When the aggregation modifier is added in such a range, the effect of suppressing the aggregation of the plasticizer can be exhibited without deteriorating the adhesive properties of the rubber-based adhesive layer.

  The rubber-based pressure-sensitive adhesive layer contains, as necessary, other components in addition to the rubber component and the aggregation modifier. Examples of other components contained in the rubber-based pressure-sensitive adhesive layer include a tackifier, a crosslinking agent, a plasticizer, and the like.

  The tackifier used for the rubber-based pressure-sensitive adhesive layer is not particularly limited, but one or more selected from various known tackifier resins can be used.

  The cross-linking agent used for the rubber-based pressure-sensitive adhesive layer is not particularly limited, and examples thereof include an isocyanate-based cross-linking agent, an epoxy-based cross-linking agent, a melamine-based cross-linking agent, a peroxide-based cross-linking agent, a urea-based cross-linking agent, and a metal alkoxide. Crosslinking agents, metal chelating crosslinking agents, metal salt crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, amine crosslinking agents, and the like. As the crosslinking agent, an isocyanate-based crosslinking agent and an epoxy-based crosslinking agent are particularly preferred. The crosslinking agents may be used alone or in combination of two or more.

  Examples of the isocyanate-based crosslinking agent include lower aliphatic polyisocyanates such as 1,2-ethylene diisocyanate, 1,4-butylene diisocyanate, and 1,6-hexamethylene diisocyanate; cyclopentylene diisocyanate, cyclohexylene diisocyanate, Alicyclic polyisocyanates such as isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated xylene diisocyanate; 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'- Aromatic polyisocyanates such as diphenylmethane diisocyanate and xylylene diisocyanate, and trimethylolpropane / tolylene diisocyanate trimer adduct [trade name "Coronate L" manufactured by Nippon Polyurethane Industry Co., Ltd. , Trimethylolpropane / hexamethylene diisocyanate trimer adduct [Nippon Polyurethane Industry Co., Ltd. under the trade name "Coronate HL"], and the like.

  Examples of the epoxy crosslinking agent include N, N, N ', N'-tetraglycidyl-m-xylenediamine, diglycidylaniline, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, 6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, penta Erythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycid Diglycidyl adipate, diglycidyl adipate, diglycidyl o-phthalate, triglycidyl-tris (2-hydroxyethyl) isocyanurate, resorcin diglycidyl ether, bisphenol-S-diglycidyl ether, two epoxy groups in the molecule Epoxy resins and the like having the above are mentioned.

  The lower limit of the amount of the crosslinking agent is appropriately set according to the purpose, and is preferably 0.1 part by mass or more based on 100 parts by mass of the rubber component. The upper limit of the amount of the crosslinking agent is appropriately set according to the purpose, and is preferably 4 parts by mass or less, more preferably 3.5 parts by mass or less, based on 100 parts by mass of the rubber component. It is more preferably at most 3.0 parts by mass, particularly preferably at most 2.5 parts by mass. When the compounding amount of the crosslinking agent is in such a range, it is easy to secure the strength of the rubber-based pressure-sensitive adhesive layer.

  The rubber-based pressure-sensitive adhesive layer contains a benzenedicarboxylic acid ester represented by the general formula (1) as a plasticizer, similarly to the PVC-based substrate.

  Examples of the benzenedicarboxylate include dialkyl phthalate, dialkyl isophthalate, and dialkyl terephthalate.

In addition, the upper limit of the number of carbon atoms of the branched alkyl group (R ¹ , R ² ) in the general formula (1) is preferably 14 or less, more preferably 13 or less, and further preferably 10 or less.

Particularly, when the branched alkyl group (R ¹ , R ² ) of the benzenedicarboxylic acid ester is a 2-ethylhexyl group or an isononyl group, the number of carbon atoms thereof is the same as the number of carbon atoms of the alkyl group (2-ethylhexyl group) of DOP. Or, because of one difference, the chemistry is very close to DOP and is suitable as a replacement for DOP.

  Preferred benzenedicarboxylic acid esters include, for example, diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), di- (2-ethylhexyl) terephthalate (DOTP, bis (2-ethylhexyl) terephthalate), diisononyl terephthalate, And diisodecyl terephthalate.

  Further preferred benzene dicarboxylic acid esters include dialkyl terephthalate in which two substituents in the benzene nucleus in the above general formula (1) are arranged at the para position (for example, di- (2-ethylhexyl) terephthalate, diisononyl terephthalate, Diisodecyl terephthalate). These are particularly preferable because they have high molecular symmetry and increase the intermolecular interaction, thereby lowering the volatility and reducing the burden on the environment.

  The lower limit of the amount of the plasticizer is appropriately set according to the purpose, and is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 15 parts by mass, based on 100 parts by mass of the rubber component. It is at least part by mass. The upper limit of the amount of the plasticizer is appropriately set depending on the purpose, and is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and still more preferably 100 parts by mass of the rubber component. Is 30 parts by mass or less. When the amount of the plasticizer is in such a range, the flexibility and the like of the rubber-based pressure-sensitive adhesive layer can be easily secured.

  As long as the object of the present invention is not impaired, the rubber-based pressure-sensitive adhesive layer includes an antioxidant, a colorant (eg, a pigment and a dye), an ultraviolet absorber, an antioxidant, a softener, a surfactant, a filler, a solvent, and a catalyst. Known additives such as a pressure-sensitive adhesive other than a rubber-based pressure-sensitive adhesive and a silane coupling agent may be blended.

  The method for forming the rubber-based pressure-sensitive adhesive layer is not particularly limited. For example, a pressure-sensitive adhesive solution in which another component such as an aggregation modifier is added to a predetermined solvent (for example, toluene) together with the rubber component is used. A method in which a rubber-based pressure-sensitive adhesive layer is formed by applying the composition on a surface of a predetermined base material (for example, a PVC-based base material) and drying the applied material.

  The thickness tb of the rubber-based pressure-sensitive adhesive layer is not particularly limited, and is appropriately set according to the purpose. The lower limit of the thickness of the rubber-based pressure-sensitive adhesive layer is, for example, preferably 1 μm or more, more preferably 2 μm or more, and still more preferably 5 μm or more. The upper limit of the thickness of the rubber-based pressure-sensitive adhesive layer is, for example, preferably 50 μm or less, more preferably 45 μm or less, and still more preferably 40 μm or less. When the thickness of the rubber-based pressure-sensitive adhesive layer is in such a range, it is easy to secure the adhesive strength, strength, and the like of the rubber-based pressure-sensitive adhesive layer.

  FIG. 2 is an explanatory diagram schematically showing another example of the adhesive tape 10A. As shown in FIG. 2, the pressure-sensitive adhesive tape 10A includes an undercoat layer 13 between a polyvinyl chloride-based substrate 11 and a rubber-based pressure-sensitive adhesive layer 12. As described above, the rubber-based pressure-sensitive adhesive tape 10A may have a configuration including the undercoat layer 13.

(Undercoat layer)
The undercoat layer is formed on one side of the film-like polyvinyl chloride-based substrate for the purpose of, for example, enhancing the anchoring property (anchor effect) on the polyvinyl chloride-based substrate. The undercoat layer is mainly composed of a material having an affinity for both the PVC-based substrate and the rubber-based pressure-sensitive adhesive layer. The undercoat layer is made of, for example, a mixed material of a material having an affinity for a PVC-based substrate (substrate-affinitive material) and a material having an affinity for a rubber-based pressure-sensitive adhesive layer (rubber-affinity material), PVC It is composed of a composite material or the like obtained by integrating a material having an affinity for the base material (substrate affinity material) and a material having an affinity for the rubber-based pressure-sensitive adhesive layer (rubber affinity material) by polymerization or the like. .

  As a material having an affinity for a polyvinyl chloride-based substrate (a material having an affinity for the substrate), polyacrylates are preferable. Polymethacrylates include (meth) acrylic acid for reasons such as enhancing adhesion to the substrate, conformability to substrate deformation, and surface smoothness of the rubber-based pressure-sensitive adhesive layer formed on the substrate. Polymers synthesized from esters (for example, acrylic acid, butyl methacrylate, ethyl methacrylate, cyclohexyl methacrylate, etc.) are preferable, and in particular, a material having affinity for the rubber-based pressure-sensitive adhesive layer (rubber-affinity material) From the viewpoint of compatibility with, a polymer synthesized from methyl methacrylate (MMA) is preferred.

  Examples of the material having affinity for the rubber-based pressure-sensitive adhesive layer (rubber-affinity material) include natural rubber, butyl-based rubber, styrene-butadiene-based rubber, and nitrile-butadiene-based rubber. In particular, because of the compatibility with the material having an affinity for the polyvinyl chloride base material (base material affinity material) and the difficulty of breaking due to the stress generated when the base material is stretched, , Natural rubber is preferred.

  A composite material in which a material having an affinity for a polyvinyl chloride-based substrate (material having an affinity for a substrate) and a material having an affinity for a rubber-based pressure-sensitive adhesive layer (a material having a rubber affinity) are integrated. Examples thereof include methyl methacrylate grafted natural rubber obtained by graft polymerization of methyl methacrylate onto natural rubber.

  In addition, the mixing ratio of the base material affinity material and the rubber affinity material in the undercoat layer is appropriately set according to the purpose. The lower limit of the mixing ratio (% by mass) of the substrate-friendly material in the undercoat layer is preferably 5% by mass or more, more preferably 5% by mass or more, based on the total mass of the substrate-friendly material and the rubber-friendly material. Is at least 10% by mass, more preferably at least 15% by mass. Further, the upper limit of the mixing ratio (% by mass) of the substrate-friendly material in the undercoat layer is preferably 50% by mass or less with respect to the total mass of the substrate-friendly material and the rubber-compatible material. It is preferably at most 40% by mass, more preferably at most 30% by mass. When the mixing ratio (% by mass) of the substrate-friendly material in the undercoat layer falls within such a range, the rubber-based pressure-sensitive adhesive layer in the rubber-based pressure-sensitive adhesive tape can be secured while maintaining the surface smoothness. And the PVC-based substrate are bonded.

  The thickness of the undercoat layer is not particularly limited, and is appropriately set according to the purpose. The lower limit of the thickness of the undercoat layer is, for example, preferably 0.1 μm or more, more preferably 0.2 μm or more, and still more preferably 0.5 μm or more. The upper limit of the thickness of the undercoat layer is, for example, preferably 10 μm or less, more preferably 5 μm or less, and further preferably 2 μm or less. When the thickness of the undercoat layer is within such a range, the rubber-based pressure-sensitive adhesive layer and the PVC-based substrate are bonded together while ensuring the surface smoothness of the rubber-based pressure-sensitive adhesive layer in the rubber-based pressure-sensitive adhesive tape.

  The pressure-sensitive adhesive tape may include a layer other than the PVC-based substrate, the rubber-based pressure-sensitive adhesive layer, and the undercoat layer as long as the object of the present invention is not impaired. As another layer, a back surface treatment agent layer (for example, a back surface treatment agent containing a release agent and a resin) formed on the back surface side (the side opposite to the side on which the rubber-based pressure-sensitive adhesive layer is formed) of the PVC base material And the like). Examples of the release agent include a silicone resin and a long-chain alkyl acrylate (co) polymer (long-chain alkyl-based release agent). Examples of the resin include a (meth) acrylic polymer and an ethylene-vinyl acetate copolymer.

(Release liner)
Before use, a rubber-based release liner may be attached to the adhesive surface of the rubber-based adhesive layer provided in the adhesive tape. As such a release liner, for example, a substrate having a release layer such as a plastic film or paper surface-treated with a release agent such as a silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide; polytetrafluoroethylene; Low-adhesive base material composed of a fluoropolymer such as polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene copolymer, chlorofluoroethylene / vinylidene fluoride copolymer; olefin-based A low-adhesion base made of a nonpolar polymer such as a resin (eg, polyethylene, polypropylene, etc.);

(Production method of adhesive tape)
The method for producing the pressure-sensitive adhesive tape is not particularly limited. For example, a method of applying a pressure-sensitive adhesive solution for forming a rubber-based pressure-sensitive adhesive on a PVC-based substrate and drying the applied material, a PVC-based Forming an undercoat layer on a material, applying an adhesive solution for forming a rubber-based adhesive on the undercoat layer, and drying the applied material, forming a rubber-based adhesive on a release liner A method of applying a pressure-sensitive adhesive solution for drying, drying the applied material, and bonding a PVC-based substrate (or a PVC-based substrate with an undercoat layer) on the applied material.

(Thickness of adhesive tape)
Although the thickness of the pressure-sensitive adhesive tape is not particularly limited, the lower limit is preferably 40 μm or more, and more preferably 50 μm or more, from the viewpoint of handleability and followability to substrate deformation such as stretching. The upper limit of the thickness of the pressure-sensitive adhesive tape is, for example, preferably 200 μm or less, and more preferably 150 μm or less.

(Ta / tb)
The ratio (ta / tb) of the thickness ta of the polyvinyl chloride base material to the thickness tb of the rubber-based pressure-sensitive adhesive layer in the pressure-sensitive adhesive tape is preferably 5 or more, more preferably 9 or more, and preferably 15 or less, more preferably Preferably it is 11 or less. When the ratio (ta / tb) is within such a range, for example, when the adhesive tape is attached to an adherend having irregularities (eg, irregularities of about 10 μm) on the surface, the surface of the adhesive tape is smoothed. Thus, the adherend can be laminated and stored with the adhesive tape adhered. Further, when the ratio (ta / tb) is in such a range, it is possible to adhere to the adherend having irregularities in a manner to follow (follow) without a gap, and to store the adherend. Water and the like can be prevented from entering between the adherend and the adhesive tape, thereby preventing the surface of the adherend from being stained.

(Plasticizer content)
The plasticizer content X (% by mass) in the adhesive tape is preferably 10% by mass or more, more preferably 15% by mass or more, preferably 50% by mass or less, more preferably 45% by mass or less. When the content X of the plasticizer in the pressure-sensitive adhesive tape is in such a range, migration of contaminants from the adhesive surface of the pressure-sensitive adhesive tape to the surface of the adherend is suppressed. The method for determining the plasticizer content X (% by mass) in the adhesive tape will be described later.

(Aggregation modifier content)
The aggregation modifier content Y (% by mass) in the pressure-sensitive adhesive tape is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, preferably 2% by mass or less, more preferably 1.% by mass or less. 5% by mass or less. When the content Y of the cohesion modifier in the pressure-sensitive adhesive tape is in such a range, migration of contaminants from the adhesive surface of the pressure-sensitive adhesive tape to the surface of the adherend is suppressed. The method for determining the aggregation modifier content Y (% by mass) in the adhesive tape will be described later.

(Aggregation modifier / plasticizer)
The ratio (aggregation modifier / plasticizer) Z of alkylphenols (aggregation modifier) to benzenedicarboxylic acid ester (plasticizer) contained in the adhesive tape is preferably 0.0005 or more, more preferably 0.001 or more. It is preferably 0.1 or less, more preferably 0.05 or less. When the ratio (aggregation modifier / plasticizer) Z in the pressure-sensitive adhesive tape is within such a range, migration of contaminants from the adhesive surface of the pressure-sensitive adhesive tape to the surface of the adherend is suppressed. The method for determining the ratio (aggregation modifier / plasticizer) Z in the adhesive tape will be described later.

(Form of adhesive tape)
The pressure-sensitive adhesive tape may be a rolled pressure-sensitive adhesive tape wound in a roll shape. The above-mentioned wound body is an adhesive tape wound body in which only an adhesive tape is wound (a rubber-based adhesive tape wound body having no winding core), and a form in which an adhesive tape is wound around a winding core in a roll shape. An adhesive tape wound body or the like may be used. The core is not particularly limited. For example, a core (plastic core) using a plastic material as a main component, and a core (paper core) using a paper material as a main component. And a core made of a metal material as a main component (metal core). Further, the adhesive tape may be in a form spread in a plane.

(Contamination prevention of adhesive tape)
The pressure-sensitive adhesive tape has a contamination-preventing property that does not cause dirt to adhere to the surface of the adherend when it is peeled off from the adherend after being attached to the adherend. The pressure-sensitive adhesive tape can exhibit anti-staining properties by including the cohesion modifier in the rubber-based pressure-sensitive adhesive layer. In addition, the evaluation method of the contamination prevention property of an adhesive tape is mentioned later.

(Maximum elongation of adhesive tape)
The maximum elongation (%) of the pressure-sensitive adhesive tape measured according to JIS K 7127 is not particularly limited, but is, for example, preferably 100% or more, and more preferably 200% or more. The upper limit of the maximum elongation (%) is not particularly limited, but is preferably, for example, about 500%. When the maximum elongation (%) of the adhesive tape is in such a range, for example, it becomes possible to follow the deformation of the adherend during drawing. In addition, when the adhesive tape is applied, it is also possible to prevent the tape from being excessively stretched due to the application stress and causing unevenness in the thickness of the tape.

(Adhesive strength of adhesive tape)
The pressure-sensitive adhesive tape has an adhesive force that can adhere to an adherend such as a metal plate in a detachable (repeelable) state. For example, at a peeling speed of 0.3 m / min against an adherend (SUS430BA plate), the adhesive force (lower limit) at 23 ° C. is preferably 0.1 (N / 20 mm) or more, 2 (N / 20 mm) or more is more preferable, and 0.3 (N / 20 mm) or more is still more preferable. Further, at a peeling speed of 0.3 m / min against the adherend (SUS430BA plate), the adhesive force (upper limit) at 23 ° C. is preferably 5 (N / 20 mm) or less, and 2.5 (N / 20 mm) or less. N / 20 mm) or less, more preferably 2 (N / 20 mm) or less. When the adhesive strength is in such a range, the adhesive tape is prevented from spontaneously peeling off from the adherend during processing (for example, drawing), and may be difficult to peel off from the adherend. Is suppressed. The adhesive strength of the adhesive tape is measured by a method described later.

(Other functions of adhesive tape)
The pressure-sensitive adhesive tape has a followability (static followability) to adherends having various surface shapes such as curved surfaces and uneven surfaces as well as flat surfaces. The adhesive tape also has a function of maintaining close contact with the adherend (dynamic followability) even when the adhesive tape is deformed together with the adherend in a state of being adhered to the adherend. The pressure-sensitive adhesive tape is also excellent in stretchability, flexibility, workability (handleability), storage stability, workability, and the like. In addition, when the adhesive tape is a roll of the adhesive tape wound in a roll shape, the operation of pulling out the tape is easy.

(Use of adhesive tape)
The adhesive tape can be used, for example, as an adhesive tape for surface protection. Specifically, it is used for applications such as an adhesive tape for surface protection when processing various metal members (for example, a metal plate) such as stainless steel and aluminum, an adhesive tape for a dicing process, and an adhesive tape for surface protection such as glass. Can be used. In addition, the adhesive tape is particularly preferable as a protective tape for drawing a metal plate among processing uses of a metal plate. The adhesive tape can follow the deformation of the metal plate as the adherend without being peeled from the adherend even if the metal plate is greatly deformed during drawing. It can be separated from the adherend without performing.

  The rubber-based pressure-sensitive adhesive tape is particularly preferably used for application to a surface of a metal member such as a metal plate. Note that a coating film or the like may be formed on the surface of the metal member. The pressure-sensitive adhesive tape may be used by attaching it to an adherend made of another member such as a resin member or glass other than the metal member.

（式中、ベンゼン核の２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）がオルト位の場合、Ｒ^１及びＲ^２は炭素数が９以上でありかつ少なくとも１つの第三級炭素原子を含む分岐アルキル基からなり、ベンゼン核の２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）がメタ位又はパラ位の場合、炭素数が８以上でありかつ少なくとも１つの第三級炭素原子を含む分岐アルキル基からなる。なお、２つの置換基（−ＣＯ_２Ｒ^１、−ＣＯ_２Ｒ^２）は、同一又は互いに異なってもよい。） (1) a polyvinyl chloride-based substrate, and a rubber-based pressure-sensitive adhesive layer formed on at least one surface of the polyvinyl chloride-based substrate, wherein the polyvinyl chloride-based substrate and the rubber-based pressure-sensitive adhesive layer are: A pressure-sensitive adhesive tape containing a benzenedicarboxylic acid ester represented by the following general formula (1) as a plasticizer, and wherein the rubber-based pressure-sensitive adhesive layer contains a cohesion modifier composed of alkylphenols.

(Wherein, when _two substituents (—CO ₂ R ¹ , —CO ₂ R ² ) of the benzene nucleus are in the ortho position, R ¹ and R ² have 9 or more carbon atoms and at least one tertiary group. It is composed of a branched alkyl group containing a carbon atom, and when two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) of the benzene nucleus are in the meta or para position, the number of carbon atoms is 8 or more and at least one It comprises a branched alkyl group containing a tertiary carbon atom.The _two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) may be the same or different.)

  (2) In the pressure-sensitive adhesive tape, the alkylphenols have an acid value of 11 to 150.

  (3) In the pressure-sensitive adhesive tape, the pressure-sensitive adhesive tape contains the benzenedicarboxylic acid ester in an amount of 10% by mass or more and 50% by mass or less.

  (4) In the pressure-sensitive adhesive tape, a ratio (mass ratio) of the alkylphenols to the benzenedicarboxylic acid ester contained in the pressure-sensitive adhesive tape is 0.0005 or more and 0.1 or less.

  (5) In the pressure-sensitive adhesive tape, a ratio (ta / tb) of a thickness ta of the polyvinyl chloride-based base material to a thickness tb of the rubber-based pressure-sensitive adhesive layer is 5 or more and 15 or less.

  (6) In the pressure-sensitive adhesive tape, the thickness ta of the polyvinyl chloride base material is 90 μm or more and 110 μm or less.

  (7) In the pressure-sensitive adhesive tape, the polyvinyl chloride base material has a maximum elongation of 100% or more as measured according to JIS-K-7127.

  (8) In the pressure-sensitive adhesive tape, the alkyl moiety of the alkylphenols is at least one selected from the group consisting of isoprene, hydrogenated isoprene, and isoprene derivatives.

  (9) In the pressure-sensitive adhesive tape, the isoprene derivative is at least one selected from the group consisting of terpenes, rosin acids, terpene derivatives, and rosin acid derivatives.

  (10) The pressure-sensitive adhesive tape is for processing a metal plate.

(11) In the pressure-sensitive adhesive tape, in the general formula (1), two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) of the benzene nucleus may be in the para position.

  (12) In the pressure-sensitive adhesive tape, the benzenedicarboxylic acid ester is at least one selected from the group consisting of bis (2-ethylhexyl) terephthalate and bisisononyl terephthalate.

  (13) In the pressure-sensitive adhesive tape, the rubber-based pressure-sensitive adhesive layer includes a natural rubber-based component and a synthetic rubber-based component as rubber components.

  (14) In the pressure-sensitive adhesive tape, the natural rubber component is obtained by graft-polymerizing an acrylic component to natural rubber at a ratio of 5 to 50% by mass.

  (15) In the pressure-sensitive adhesive tape, an undercoat layer is interposed between the polyvinyl chloride-based substrate and the rubber-based pressure-sensitive adhesive layer.

  Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited by these examples.

[Example 1]
(Preparation of polyvinyl chloride base material)
For 100 parts by mass of polyvinyl chloride (degree of polymerization P = 100), 30 parts by mass of DOTP (plasticizer, bis (2-ethylhexyl) terephthalate, manufactured by ADEKA Corporation) and 30 parts by mass of methylenebisstearic acid amide (trade name: Bisamide LA "(manufactured by Nippon Kasei Co., Ltd.) was added to 1 part by mass of soft polyvinyl chloride, which was formed into a film by a calendering method to obtain a soft polyvinyl chloride film (polyvinyl chloride base material). . The thickness of the obtained soft polyvinyl chloride film is 110 μm, the elastic modulus (MD: Machine Direction) measured according to JIS-K-7127 is 250 MPa, and the maximum elongation measured according to JIS-K-7127. (MD) was 400%. The surface roughness (arithmetic mean surface roughness Ra) of the soft polyvinyl chloride film immediately after production was 0.1 μm. The arithmetic average surface roughness Ra was measured using a scanning probe microscope (the same applies to the arithmetic average surface roughness Ra in other examples described later).

(Formation of undercoat layer)
30 parts by weight (solid content) of natural rubber (natural rubber latex, trade name “HYTEX HA”, manufactured by Nomura Trading Co., Ltd., concentration: 62.0% by mass), methyl methacrylate (MMA, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 47 parts by mass, 1.01 part by mass of polyoxyethylene alkyl phenyl ether (surfactant, trade name "Neugen EA-190D", manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), cumene hydroperoxide (polymerization initiator, trade name " Parkmill H-80 ", an aqueous solution consisting of a mixture of 0.48 parts by mass of tetraethylene pentamine (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.34 parts by mass of tetraethylenepentamine was maintained at 40 ° C. for 2 hours. Then, methyl methacrylate is graft-polymerized on natural rubber to obtain MMA-grafted natural rubber (MMA-g-NR) (acrylic component content: 27% by mass). To obtain a polymer solution (1) containing.

  The aqueous polymer solution (1) was applied to one surface of the above soft polyvinyl chloride film, and the applied material was dried to form an undercoat layer. The thickness of the undercoat layer was 1.0 μm, and the arithmetic average surface roughness Ra was 0.5 μm.

(Formation of rubber-based pressure-sensitive adhesive layer)
First, MMA-grafted natural rubber I (MMA-g-NR-I) used for the rubber-based pressure-sensitive adhesive layer was produced as follows.

  85 parts by mass of MMA-grafted natural rubber I (MMA-g-NR-I), 15 parts by mass of chloroprene-based rubber (CR, chloroprene / methacrylic acid copolymer, trade name “Skyprene 570”, manufactured by Tosoh Corporation), terpene 5 parts by mass of phenolic resin (aggregation modifier, trade name "Sumilite Resin PR-12603", manufactured by Sumitomo Bakelite Co., Ltd., acid value: 65), isocyanate-based crosslinking agent (aromatic polyisocyanate, trade name "Coronate L") 2 parts by mass, manufactured by Nippon Polyurethane Industry Co., Ltd., an ultraviolet absorber (pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]), "SONGNOX1010PW", Sakai Chemical Industry Co., Ltd. 3 parts by mass, DOTP (plasticizer, bis (2-ethylhexyl terephthalate) , Ltd. J-PLUS) 40 parts by mass, to obtain a pressure-sensitive adhesive solution A was added to a predetermined amount of toluene.

  The pressure-sensitive adhesive solution A is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Example 1 was obtained.

[Example 2]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  A pressure-sensitive adhesive solution was prepared in the same manner as in Example 1, except that 3 parts by mass of a terpene phenol resin (trade name “Tamanol 901”, manufactured by Arakawa Chemical Industries, Ltd., acid value: 90) was used as the aggregation modifier. B was prepared.

  The pressure-sensitive adhesive solution B is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Example 2 was obtained.

[Example 3]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  An adhesive solution C was prepared in the same manner as in Example 1 except that the amount of the aggregation modifier was changed to 30 parts by mass.

  The pressure-sensitive adhesive solution C is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Example 3 was obtained.

[Example 4]
The same soft polyvinyl chloride film as in Example 1 was prepared. In the fourth embodiment, the undercoat layer as in the first embodiment is not formed.

  The same pressure-sensitive adhesive solution A as in Example 1 was prepared, and the pressure-sensitive adhesive solution A was applied to one side of a soft polyvinyl chloride film, and the applied material was dried by heating at 130 ° C. for 90 seconds to obtain a film having a thickness of 10 μm. Was formed. Thus, the pressure-sensitive adhesive tape of Example 4 was obtained.

[Example 5]
The same soft polyvinyl chloride film as in Example 1 was prepared.

  Except that the blending amount of methyl methacrylate was changed to 48 parts by mass, methacrylic acid was graft-polymerized to natural rubber in the same manner as in Example 1 to obtain an MMA-grafted natural rubber (MMA-g-NR) (acrylic). (Polymer content: 35% by mass) was obtained.

  The aqueous polymer solution (2) was applied to one surface of the above soft polyvinyl chloride film, and the applied material was dried to form an undercoat layer. The thickness of the undercoat layer was 1.0 μm, and the arithmetic average surface roughness Ra was 0.5 μm.

  The same pressure-sensitive adhesive solution A as in Example 1 was prepared, and the pressure-sensitive adhesive solution A was applied to one side of the above soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material was heated at 130 ° C. for 90 seconds. The resultant was dried to form a rubber-based pressure-sensitive adhesive layer having a thickness of 10 μm. Thus, the pressure-sensitive adhesive tape of Example 5 was obtained.

[Example 6]
The same soft polyvinyl chloride film as in Example 1 was prepared.

  An adhesive solution D was obtained in the same manner as in Example 1, except that the amount of the plasticizer (DOTP) was changed to 20 parts by mass.

  An undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface of the flexible polyvinyl chloride film.

  The pressure-sensitive adhesive solution D is applied to one side of the soft polyvinyl chloride film in a form of being laminated on the undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based pressure-sensitive adhesive having a thickness of 10 μm. A layer was formed. Thus, the pressure-sensitive adhesive tape of Example 6 was obtained.

[Example 7]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  100 parts by mass of chloroprene rubber (CR, chloroprene / methacrylic acid copolymer, trade name “Skyprene 570”, manufactured by Tosoh Corporation), terpene phenol resin (aggregation modifier, trade name “Sumilite Resin PR-12603”) 5 parts by mass, manufactured by Sumitomo Bakelite Co., Ltd., acid value: 65), 2 parts by mass of an isocyanate-based crosslinking agent (aromatic polyisocyanate, trade name "Coronate L", manufactured by Nippon Polyurethane Industry Co., Ltd.), an ultraviolet absorber (pentaerythritol) -Tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], "SONGNOX1010PW", manufactured by Sakai Chemical Industry Co., Ltd.) 3 parts by mass, DOTP (plasticizer, bis (2-terephthalate) 40 parts by mass of ethylhexyl) and J-Plus Co., Ltd. It was added to give an adhesive solution E to.

  The pressure-sensitive adhesive solution E is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Example 7 was obtained.

Example 8
A soft polyvinyl chloride film (polyvinyl chloride base material) was obtained in the same manner as in Example 1 except that 30 parts by mass of DINP (diisononyl phthalate) was used as a plasticizer and the thickness was changed to 90 μm. Was. The elastic modulus (MD: Machine Direction) of the obtained flexible polyvinyl chloride film measured according to JIS-K-7127 is 250 MPa, and the maximum elongation (MD) measured according to JIS-K-7127 is 400%. Met. The surface roughness (arithmetic mean surface roughness Ra) of the soft polyvinyl chloride film immediately after production was 0.1 μm.

  An undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface of the flexible polyvinyl chloride film.

  The same pressure-sensitive adhesive solution A as in Example 1 was prepared, and the pressure-sensitive adhesive solution A was applied to one side of the above soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material was heated at 130 ° C. for 90 seconds. The resultant was dried to form a rubber-based pressure-sensitive adhesive layer having a thickness of 10 μm. Thus, the pressure-sensitive adhesive tape of Example 8 was obtained.

[Example 9]
The same soft polyvinyl chloride film as in Example 1 was prepared.

  Except that the blending amount of methyl methacrylate was changed to 21 parts by mass, methacrylic acid was graft-polymerized to natural rubber in the same manner as in Example 1 to obtain MMA-grafted natural rubber (MMA-g-NR) (acrylic). A polymer aqueous solution (3) containing a component content of 15% by mass) was obtained.

  The aqueous polymer solution (3) was applied to one surface of the above soft polyvinyl chloride film, and the applied material was dried to form an undercoat layer. The thickness of the undercoat layer was 1.0 μm, and the arithmetic average surface roughness Ra was 0.5 μm.

  The same pressure-sensitive adhesive solution A as in Example 1 was prepared, and the pressure-sensitive adhesive solution A was applied to one side of the above soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material was heated at 130 ° C. for 90 seconds. The resultant was dried to form a rubber-based pressure-sensitive adhesive layer having a thickness of 10 μm. Thus, the pressure-sensitive adhesive tape of Example 9 was obtained.

[Example 10]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  A pressure-sensitive adhesive solution was prepared in the same manner as in Example 1, except that 5 parts by mass of a rosin-modified phenol (trade name “Tamanol 135”, manufactured by Arakawa Chemical Industries, Ltd., acid value: 18) was used as the aggregation modifier. F was produced.

  The pressure-sensitive adhesive solution F is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Example 10 was obtained.

[Example 11]
A soft polyvinyl chloride film (polyvinyl chloride-based substrate) was obtained in the same manner as in Example 1 except that the amount of the plasticizer (DOTP) was changed to 20 parts by mass. The thickness of the obtained flexible polyvinyl chloride film is 110 μm, the elastic modulus (MD: Machine Direction) measured according to JIS-K-7127 is 350 MPa, and the maximum elongation measured according to JIS-K-7127. (MD) was 300%. The surface roughness (arithmetic mean surface roughness Ra) of the soft polyvinyl chloride film immediately after production was 0.1 μm.

  An undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface of the flexible polyvinyl chloride film, and further laminated on the undercoat layer. The same rubber-based pressure-sensitive adhesive layer (thickness: 10 μm) as in Example 1 was formed to obtain a pressure-sensitive adhesive tape of Example 11.

[Example 12]
A soft polyvinyl chloride film (polyvinyl chloride-based substrate) was obtained in the same manner as in Example 1 except that the amount of the plasticizer (DOTP) was changed to 40 parts by mass. The thickness of the obtained soft polyvinyl chloride film is 110 μm, the elastic modulus (MD: Machine Direction) measured according to JIS-K-7127 is 150 MPa, and the maximum elongation measured according to JIS-K-7127. (MD) was 500%. The surface roughness (arithmetic mean surface roughness Ra) of the soft polyvinyl chloride film immediately after production was 0.1 μm.

  An undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface of the flexible polyvinyl chloride film, and further laminated on the undercoat layer. The same rubber-based pressure-sensitive adhesive layer (thickness: 10 μm) as in Example 1 was formed to obtain a pressure-sensitive adhesive tape of Example 12.

[Comparative Example 1]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  Example 1 except that 20 parts by mass of a terpene polymer (containing no phenol residue) (trade name “YS Resin PX1150”, manufactured by Yashara Chemical Co., Ltd., acid value: 1) was used instead of the aggregation modifier. In the same manner as in the above, an adhesive solution G was prepared.

  The pressure-sensitive adhesive solution G is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Comparative Example 1 was obtained.

[Comparative Example 2]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  Instead of using 5 parts by mass of an aliphatic hydrocarbon resin (containing no phenol residue) (trade name “Alcon P-100”, manufactured by Arakawa Chemical Industries, Ltd., acid value: 0) instead of the aggregation modifier. In the same manner as in Example 1, an adhesive solution H was prepared.

  The pressure-sensitive adhesive solution H is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Comparative Example 2 was obtained.

[Comparative Example 3]
A soft polyvinyl chloride film similar to that of Example 1 was prepared, and an undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface thereof.

  Except that 5 parts by mass of a rosin polymer (containing no phenol residue) (trade name “Pine Crystal KE-100”, manufactured by Arakawa Chemical Industries, Ltd., acid value: 10) was used instead of the aggregation modifier. In the same manner as in Example 1, an adhesive solution I was prepared.

  The pressure-sensitive adhesive solution I is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the adhesive tape of Comparative Example 3 was obtained.

[Comparative Example 4]
A soft polyvinyl chloride film (polyvinyl chloride base material) was obtained in the same manner as in Example 1, except that 30 parts by mass of DINP (diisononyl phthalate) was used as a plasticizer. The elastic modulus (MD: Machine Direction) of the obtained flexible polyvinyl chloride film measured according to JIS-K-7127 is 250 MPa, and the maximum elongation (MD) measured according to JIS-K-7127 is 400%. Met. The surface roughness (arithmetic mean surface roughness Ra) of the soft polyvinyl chloride film immediately after production was 0.1 μm.

  An undercoat layer (thickness: 1.0 μm, arithmetic average surface roughness Ra: 0.5 μm) similar to that of Example 1 was formed on one surface of the flexible polyvinyl chloride film.

  Example 1 except that 20 parts by mass of a terpene polymer (containing no phenol residue) (trade name “YS Resin PX1150”, manufactured by Yashara Chemical Co., Ltd., acid value: 1) was used instead of the aggregation modifier. In the same manner as in the above, an adhesive solution J was prepared.

  The pressure-sensitive adhesive solution J is applied to one side of the soft polyvinyl chloride film in a form of being laminated on an undercoat layer, and the applied material is dried by heating at 130 ° C. for 90 seconds to obtain a rubber-based pressure-sensitive adhesive having a thickness of 10 μm. An agent layer was formed. Thus, the pressure-sensitive adhesive tape of Comparative Example 4 was obtained.

(Plasticizer content)
With respect to the pressure-sensitive adhesive tapes of Examples and Comparative Examples, the plasticizer content X (% by mass) in the pressure-sensitive adhesive tapes was determined by using the following formula (I).

(Formula (I))
X = {(W1 × L1 × T1 × A1) × (B1 / (B1 + C))} + {(W2 × L2 × T2 × A2) × (B2 / E)} / ｛(W1 × L1 × T1 × A1) + (W2 × L2 × T2 × A2)｝

The parameters of the above formula (I) are as follows. Here, the “substrate” is a soft polyvinyl chloride film (polyvinyl chloride-based substrate), which is in a state before an adhesive is applied. The “adhesive” here is in a state before being applied to a substrate.
W1: substrate width (cm), L1: substrate length, T1: substrate thickness (cm), B1: number of plasticizer parts (parts by mass) in the substrate, C: number of PVC parts in the substrate (mass) Part), A1: Specific gravity of substrate (g / cm ³ )
W2: adhesive application width (cm), L2: adhesive application length (cm), T2: adhesive application thickness (cm), A2: specific gravity of the adhesive (g / cm ³ ), B2: adhesive Number of plasticizer parts (parts by mass), D: number of aggregation modifiers in the adhesive (parts by mass), E: number of parts of the adhesive (parts by mass)

In the pressure-sensitive adhesive tapes of Examples and Comparative Examples, W1 = W2 and L1 = L2. Therefore, the above calculation formula (I) is summarized as follows.
X = {(T1 × A1) × (B1 / (B1 + C) + (T2 × A2) × (B2 / E)} / {(T1 × A1) + (T2 × A2)}

Further, A1 was 1.25 g / cm ³ and A2 was 0.93 g / cm ³ . Tables 1 and 2 show the plasticizer content X (% by mass) of each Example and each Comparative Example.

(Aggregation modifier content)
With respect to the pressure-sensitive adhesive tapes of Examples and Comparative Examples, the aggregation modifier content Y (% by mass) in the pressure-sensitive adhesive tapes was determined using the following calculation formula (2).

(Formula (II))
Y = {(W2 × L2 × T2 × A2) × (D / E)} / {(W1 × L1 × T1 × A1) + (W2 × L2 × T2 × A2)}

  Each parameter of the above formula (II) is the same as that used in the above formula (I).

In addition, in the pressure-sensitive adhesive tapes of Examples and Comparative Examples, since W1 = W2 and L1 = L2, the above-described calculation formula (II) is summarized as follows.
Y = (A2 × D / E) / (A1 + A2)

  Tables 1 and 2 show the aggregation modifier content Y (% by mass) of each of the examples and comparative examples.

[Aggregation modifier / plasticizer]
For the pressure-sensitive adhesive tapes of the respective examples and comparative examples, the ratio of alkylphenols (aggregation modifier) to benzenedicarboxylic acid ester (plasticizer) contained in the pressure-sensitive adhesive tapes, using the calculation formula (3) shown below. (Aggregation modifier / plasticizer) Z was determined.

(Formula (III))
Z = {(W2 × L2 × T2 × A2) × (D / E)} / {(W1 × L1 × T1 × A1) × (B1 / (B1 + C))} + {(W2 × L2 × T2 × A2) × (B2 / E)｝

  Each parameter of the above formula (III) is the same as that used in the above formula (I).

In the pressure-sensitive adhesive tapes of Examples and Comparative Examples, W1 = W2 and L1 = L2. Therefore, the above formula (III) is summarized as follows.
Z = {A2 × (D / E)} / {A1 × (B1 / (B1 + C))} + {A2 × (B2 / E)}

  Tables 1 and 2 show the ratio (aggregation modifier / plasticizer) Z of each example and each comparative example.

[Evaluation 1: Measurement of maximum elongation (%) of adhesive tape]
The maximum elongation (MD) in the MD direction of each of the pressure-sensitive adhesive tapes of the examples and the comparative examples was measured in accordance with JIS-K-7127. The measurement results are shown in Tables 1 and 2.

[Evaluation 2: Measurement of 180 ° Peeling Adhesive Strength (1)]
A test sample having a width of 20 mm and a length of 100 mm was cut out from the adhesive tape obtained in each of the examples and the comparative examples. The adhesive surface of the test sample was bonded to a SUS plate (SUS304 plate) under the condition of 23 ° C. and 50% RH by reciprocating a roller having a weight of 2.0 kg and a width of 30 mm once. After being left for 30 minutes under the conditions of 23 ° C. and 50% RH, a 180 ° peel test was performed using a tensile tester at a tensile speed of 0.3 m / min according to JIS Z 0237, and peeling was performed. The adhesive strength (N / 20 mm) was measured. The measurement results are shown in Tables 1 and 2.

[Evaluation 3: Measurement of 180 ° peel adhesion (2)]
Except that the pulling speed was changed to 30 m / min, the peeling adhesive force (N / 20 mm) of the pressure-sensitive adhesive tape (test sample) obtained in each of Examples and Comparative Examples was measured in the same manner as in the measurement method of Evaluation 2. ) Was measured. The measurement results are shown in Tables 1 and 2.

[Evaluation 4: Measurement of 180 ° Peeling Adhesive Strength (3)]
Except that the temperature condition was changed to 0 ° C., the peeling adhesive force (N / 20 mm) of the adhesive tape (test sample) obtained in each Example and each Comparative Example was obtained in the same manner as in the measurement method of Evaluation 2. Was measured. The measurement results are shown in Tables 1 and 2.

[Evaluation 5: Pollution prevention property]
A test sample was obtained by cutting the adhesive tape obtained in each of the examples and comparative examples into a predetermined size. Further, a SUS plate (SUS430BA plate) that was subjected to ultrasonic cleaning using toluene was prepared. The test sample was stuck on a SUS plate at a linear pressure of 78.5 N / cm at a speed of 0.3 m / min, and the SUS plate stuck with the test sample was placed in an environment of a temperature of 40 ° C. and a humidity of 92% RH. For 6 days. Thereafter, the test sample was peeled from the SUS plate under the conditions of a temperature of 23 ° C. and a humidity of 50% RH under the conditions of a peel angle of 180 ° and a peel speed of 30 m / min. Thereafter, the gloss value (measuring angle: 20 degrees) of the gloss value of the surface of the SUS plate at the portion where the test sample was stuck was measured using a micro trigloss meter (manufactured by BYK Gardner). When the gloss value was 800 or more, it was determined that there was no contamination prevention property. When the gloss value was less than 800, it was determined that there was no contamination prevention property. The results are shown in Tables 1 and 2. In Tables 1 and 2, the case where there is contamination prevention is indicated by “○”, and the case where there is no contamination prevention is indicated by “×”.

  As shown in Table 1, it was confirmed that the pressure-sensitive adhesive tapes of Examples 1 to 12 in which the cohesion modifier (alkylphenols) was blended in the rubber-based pressure-sensitive adhesive layer had antifouling properties.

  On the other hand, the pressure-sensitive adhesive tapes of Comparative Examples 1 to 4, in which various substances containing no phenol residue are blended in the rubber-based pressure-sensitive adhesive layer, do not have contamination prevention properties, as shown in Table 2. It was confirmed that the surface of the SUS plate after the adhesive tape had been peeled had stains that could be visually confirmed.

  In each pressure-sensitive adhesive tape, a plasticizer such as DOTP blended in the polyvinyl chloride-based substrate is presumed to migrate to the rubber-based pressure-sensitive adhesive layer by molecular diffusion. Unlike the polyvinyl chloride, the rubber-based pressure-sensitive adhesive layer has a low affinity for a plasticizer such as DOTP, and it is presumed that the transferred plasticizer is likely to aggregate in the rubber-based pressure-sensitive adhesive layer. DOTP is also a substance that is more easily crystallized than DOP conventionally used.

  Therefore, in the pressure-sensitive adhesive tape of each comparative example, it is presumed that, in the rubber-based pressure-sensitive adhesive layer, a portion in which the properties become non-uniform due to coagulation of the plasticizer and solidification caused by the plasticizer occurs. Is done. In such a pressure-sensitive adhesive tape, a portion where the rubber-based pressure-sensitive adhesive layer is partially torn due to the aggregation of the plasticizer itself or the concentration of the peeling stress due to the non-uniform pressure-sensitive adhesive property is the adherend (SUS plate). ) It is presumed to cause surface contamination.

  On the other hand, in the pressure-sensitive adhesive tapes of the examples, when the cohesion modifier (alkylphenols) is blended in the rubber-based pressure-sensitive adhesive layer, the coagulation of the plasticizer and the property of the rubber-based pressure-sensitive adhesive layer are not improved. It is assumed that homogenization and the like are suppressed, and as a result, contamination of the surface of the adherend (SUS plate) is suppressed as described above.

  The cohesion modifier of each embodiment has a structure having both a hydrophobic alkyl group and a hydrophilic phenolic hydroxyl group. Therefore, the alkyl group has a suitable affinity for the rubber-based pressure-sensitive adhesive, and the phenolic hydroxyl group has a suitable affinity for a plasticizer such as DOTP. It is presumed that aggregation of a plasticizer such as DOTP in the layer can be suppressed.

  Here, the adhesive tapes of Example 1, Example 11 and Example 12 are compared. The pressure-sensitive adhesive tape of Example 11 has a smaller amount of the plasticizer in the base material than in Example 1, and the pressure-sensitive adhesive tape of Example 12 has a smaller amount of plasticizer in the base material than in Example 1. This is the case when the compounding amount of the agent is large. The pressure-sensitive adhesive tapes of Examples 11 and 12 were the same as Example 1 except for the amount of the plasticizer in the base material. Among them, the adhesive tape having the highest gloss value and the excellent anti-staining property is the pressure-sensitive adhesive tape of Example 11 (gloss value: 912) containing the least amount of the plasticizer in the base material. On the other hand, the adhesive tape of Example 12 (gloss value: 809), which has the lowest gloss value and is poor in anti-staining properties, has the largest amount of the plasticizer in the base material. Thus, although the base material of the pressure-sensitive adhesive tape is not a part in direct contact with the adherend, the degree of contamination on the surface of the adherend varies depending on the amount of the plasticizer incorporated in the base material. (That is, if the amount of plasticizer in the substrate increases, the contamination on the adherend surface increases, and if the amount of plasticizer in the substrate decreases, the contamination on the adherend surface decreases) Was done.

  Next, the adhesive tapes of Example 1 and Example 6 are compared. The pressure-sensitive adhesive tape of Example 6 has a smaller amount of the plasticizer in the pressure-sensitive adhesive layer than that of Example 1. Other conditions of the pressure-sensitive adhesive tape of Example 6 are the same as those of Example 1. The adhesive tape of Example 6 has a lower gloss value than that of Example 1. The pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape is a portion that directly contacts the adherend. It was confirmed that the larger the amount of the plasticizer contained in the pressure-sensitive adhesive layer (Example 1), the more excellent the contamination prevention property (the higher the gloss value).

  10, 10A: adhesive tape, 11: polyvinyl chloride base material, 12: rubber adhesive layer, 13: undercoat layer

Claims (10)

A polyvinyl chloride base material,
A rubber-based pressure-sensitive adhesive layer formed on at least one surface of the polyvinyl chloride-based substrate,
The polyvinyl chloride-based substrate and the rubber-based pressure-sensitive adhesive layer contain a benzenedicarboxylic acid ester represented by the following general formula (1) as a plasticizer,
A pressure-sensitive adhesive tape, wherein the rubber-based pressure-sensitive adhesive layer contains a cohesion modifier composed of alkylphenols.

(Wherein, when _two substituents (—CO ₂ R ¹ , —CO ₂ R ² ) of the benzene nucleus are in the ortho position, R ¹ and R ² have 9 or more carbon atoms and at least one tertiary group. It is composed of a branched alkyl group containing a carbon atom, and when two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) of the benzene nucleus are in the meta or para position, the number of carbon atoms is 8 or more and at least one It comprises a branched alkyl group containing a tertiary carbon atom.The _two substituents (—CO ₂ R ¹ and —CO ₂ R ² ) may be the same or different.)   The pressure-sensitive adhesive tape according to claim 1, wherein the alkylphenol has an acid value of 11 to 150.   The pressure-sensitive adhesive tape according to claim 1, wherein the benzenedicarboxylic acid ester is contained in the pressure-sensitive adhesive tape in an amount of 10% by mass or more and 50% by mass or less.   The pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein a ratio (mass ratio) of the alkylphenols to the benzenedicarboxylic acid ester contained in the pressure-sensitive adhesive tape is from 0.0005 to 0.1.   The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein a ratio (ta / tb) of a thickness ta of the polyvinyl chloride base material to a thickness tb of the rubber-based pressure-sensitive adhesive layer is 5 or more and 15 or less.   The pressure-sensitive adhesive tape according to any one of claims 1 to 5, wherein a thickness ta of the polyvinyl chloride base material is 90 µm or more and 110 µm or less.   The pressure-sensitive adhesive tape according to any one of claims 1 to 6, wherein a maximum elongation of the polyvinyl chloride base material measured according to JIS-K-7127 is 100% or more.   The pressure-sensitive adhesive tape according to any one of claims 1 to 7, wherein the alkyl moiety of the alkylphenol is at least one selected from the group consisting of isoprene, hydrogenated isoprene, and isoprene derivatives.   The pressure-sensitive adhesive tape according to claim 8, wherein the isoprene derivative is at least one selected from the group consisting of terpenes, rosin acids, terpene derivatives, and rosin acid derivatives.   The pressure-sensitive adhesive tape according to any one of claims 1 to 9, which is used for processing a metal plate.

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