JP5073277B2 - Film base and adhesive tape - Google Patents

Description

The present invention relates to a film substrate and an adhesive tape using the film substrate.

As various adhesive tapes such as insulating tapes used for various electrical equipment in automobiles, railways, aircraft, ships, houses, factories, etc., it has moderate flexibility and extensibility, flame resistance, mechanical strength, Films made from a resin composition containing a vinyl halide resin such as polyvinyl chloride have been used because of its excellent heat-resistant deformation, electrical insulation and moldability, and relatively low cost. It was. However, since vinyl halide resin films generate toxic gases when incinerated, recently, inorganic polyolefins such as metal hydroxides (such as magnesium hydroxide and aluminum hydroxide) that have a low environmental impact. A film using a non-halogen resin composition containing a large amount of an inorganic flame retardant composed of a metal compound as a raw material has begun to be used.

As an adhesive tape using a film made of such a non-halogen resin composition as a raw material, a composition containing an olefin polymer and an inorganic flame retardant as a film base (for example, Patent Document 1), A material for forming an olefin film, a styrene / ethylene / butylene copolymer / styrene block polymer such as styrene as a film base (for example, Patent Document 2), a vinyl aromatic elastomer component and a styrene polymer The thing (for example, patent document 3) made into the olefin resin composition film base material containing a component is known.
JP 2001-192629 A JP 2000-038550 A JP 2002-105217 A

However, conventional adhesive tapes using films made from non-halogen resin compositions are flexible and easy to cut when used as a tape for bundling complex wires and cables in the engine room of automobiles, for example. However, none satisfying all of the characteristics such as heat resistance, wear resistance, and weather resistance has been obtained. The present invention provides a film base material having a good balance of flexibility, hand cutting properties (easy to cut), heat resistance, wear resistance, and weather resistance, and an adhesive tape using the film base material. The purpose is to do.

（式中、ｎは１〜１００の整数、Ｒ_１、Ｒ_２、はそれぞれ独立にＣ１−２４のアルキル基を表す。）

（式中、ｎは１〜１００の整数、Ｒ_１、Ｒ_２、はそれぞれ独立にＣ１−２４のアルキル基を表す。） That is, the present invention relates to an aromatic vinyl elastomer, a styrene copolymer comprising 80 to 99% by mass of an aromatic vinyl monomer and 1 to 20% by mass of an ethylenically unsaturated carboxylic acid monomer, and a styrene And an ethylenic unsaturation in the styrenic copolymer having at least one molecular skeleton selected from the following general formulas (Chemical Formula 3) and (Chemical Formula 4) It is a film base material which contains 0.01-5 mass parts with respect to 100 mass parts of aromatic vinyl-type elastomers of the hindered amine stabilizer which does not react with carboxylic acid.

(In the formula, n is an integer of 1 to 100, and R ₁ and R ₂ each independently represents a C1-24 alkyl group.)

(In the formula, n is an integer of 1 to 100, and R ₁ and R ₂ each independently represents a C1-24 alkyl group.)

In the present invention, at least one selected from the following embodiments (1) to (8) is preferably provided.
(1) A film substrate containing 1 to 50 parts by mass of a styrene copolymer and 1 to 60 parts by mass of a styrene resin with respect to 100 parts by mass of an aromatic vinyl elastomer.
(2) The aromatic vinyl elastomer is a styrene-butadiene random copolymer, a styrene-butadiene block copolymer, a hydrogenated styrene-butadiene random copolymer, and a hydrogenated styrene-butadiene block copolymer. A film substrate which is at least one selected from the group consisting of:
(3) The film base material in which the ethylenically unsaturated carboxylic acid contained in the styrene copolymer is methacrylic acid.
(4) The film base material in which the styrene resin is a polystyrene resin (GPPS) and / or a rubber-reinforced polystyrene resin (HIPS).
(5) The film base material whose acid dissociation index pKa value of the hindered amine stabilizer is 6.5 or less.
(6) A film base material having a Vicat softening point of 100 to 130 ° C. of the styrene copolymer.
(7) A film substrate containing 1 to 300 parts by mass of an inorganic filler with respect to 100 parts by mass of the aromatic vinyl elastomer.
(8) An adhesive tape having an adhesive layer formed on one side of a film substrate.
The adhesive tape can be used as a binding adhesive tape.

By using the film substrate of the present invention, it is possible to obtain a pressure-sensitive adhesive tape having a good balance of flexibility, hand cutting, heat resistance, wear resistance, and weather resistance.

The aromatic vinyl-based elastomer that can be used for the film substrate of the present invention comprises an aromatic vinyl hydrocarbon polymer block and an elastomeric polymer block, and the aromatic vinyl hydrocarbon polymer block is hard. The segment is preferably one in which an elastomeric polymer block constitutes a soft segment. The aromatic vinyl elastomer is typically an aromatic vinyl hydrocarbon polymer block-elastomeric polymer block, or an aromatic vinyl hydrocarbon polymer block-elastomeric polymer block-aromatic vinyl hydrocarbon heavy. A block copolymer having a copolymer structure represented by a polymer block, wherein a double bond of an elastomeric polymer block may be partially or completely hydrogenated, or a random copolymer, Generally known as a styrenic elastomer.

Examples of the aromatic vinyl hydrocarbon constituting the aromatic vinyl hydrocarbon polymer block include styrene, α-methylstyrene, o-, m-, and p-methylstyrene, 1,3-dimethylstyrene, vinylnaphthalene, and vinyl. Anthracene and the like can be mentioned, among which styrene is preferable. In addition, the elastomeric polymer block may be conjugated diene or other than conjugated diene as long as it exhibits elastomeric properties, but generally conjugated diene is preferable. Examples of the conjugated diene in this case include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like.

Examples of aromatic vinyl elastomers include styrene-ethylene / butylene copolymer-styrene (SEBS), styrene-ethylene / propylene copolymer-styrene (SEPS), styrene-butadiene-styrene (SBS), and styrene-isoprene-styrene. ABB type block copolymer or random copolymer such as (SIS), or a hydrogenated product of these ABA type block copolymer or random copolymer; styrene-butadiene copolymer Examples thereof include an AB block copolymer or a random copolymer such as a polymer, a styrene-isoprene copolymer, or a hydrogenated product of these AB block copolymer or random copolymer. it can. Aromatic vinyl elastomers include, among others, styrene-butadiene random copolymers, styrene-butadiene block copolymers, hydrogenated styrene-butadiene random copolymers, and hydrogenated styrene-butadiene block copolymers. preferable. In particular, a completely hydrogenated product of a styrene-butadiene random copolymer is more preferable because it has a low elongation at break.

The styrene copolymer in the film substrate of the present invention is obtained by polymerizing 80 to 99% by mass of an aromatic vinyl monomer and 1 to 20% by mass of an ethylenically unsaturated carboxylic acid monomer. Preferably, 85 to 98% by mass of an aromatic vinyl monomer, 2 to 15% by mass of an ethylenically unsaturated carboxylic acid monomer, and 0.1 to 10% by mass of a vinyl monomer copolymerizable therewith are polymerized. It is made. When the aromatic vinyl monomer is less than 80% by mass or the ethylenically unsaturated carboxylic acid monomer exceeds 20% by mass, the fluidity of the resin is lowered, and the difference in melt viscosity from the aromatic vinyl elastomer increases. Since the melt mixing becomes worse, the moldability of the film substrate is lowered. On the other hand, when the aromatic vinyl monomer exceeds 99% by mass or the ethylenically unsaturated carboxylic acid monomer is less than 1% by mass, the heat resistance imparting effect as a film substrate is deteriorated.

Examples of the aromatic vinyl monomer of the styrene copolymer include styrenes such as styrene, α-methylstyrene, vinyltoluene, ethylstyrene, and t-butylstyrene, and substituted products thereof. Preferably, it is styrene that makes it easy to control the molecular weight increased by the reaction.

Examples of the ethylenically unsaturated carboxylic acid monomer of the styrene copolymer include acrylic acid or esters thereof, methacrylic acid or esters thereof, α, β-unsaturated dicarboxylic acids such as fumaric acid, maleic acid, and itaconic acid. Or intramolecular dehydration (or dealcoholization) of monomer units such as monoesters, diesters, anhydrides or imidized products thereof, acrylonitrile, or acrylic acid, methacrylic acid or esters thereof adjacent in the molecule. Examples thereof include 6-membered cyclic anhydrides or imidized products thereof that are secondarily derived from the reaction. Of these, methacrylic acid, maleic acid, and imidized products are preferable.

Examples of vinyl monomers copolymerizable with an aromatic vinyl monomer of a styrene copolymer and an ethylenically unsaturated carboxylic acid include (meth) acrylic acid ester monomers such as methyl methacrylate and n-butyl acrylate ; Unsaturated carboxylic acid monomers other than methacrylic acid such as vinyl cyanide monomers such as acrylonitrile and methacrylonitrile, maleic anhydride, maleic acid, itaconic acid, itaconic anhydride; maleimide, N-methylmaleimide, N -Maleimide monomers such as phenylmaleimide. These may be used alone or in combination of two or more.

The Vicat softening point of the styrene copolymer is 100 to 130 ° C, preferably 110 to 120 ° C. This is because, in the case of a styrene copolymer having a Vicat softening point of less than 100 ° C., the film base material may be thermally contracted, resulting in poor heat resistance. On the other hand, in the case of a styrene copolymer having a Vicat softening point of more than 130 ° C., fish eyes due to poor mixing may occur, and the appearance of the film substrate may be poor due to the occurrence of pinholes.

The blending amount of the styrene copolymer in the film substrate of the present invention is in the range of 1 to 50 parts by mass, preferably 10 to 35 parts by mass with respect to 100 parts by mass of the aromatic vinyl elastomer. When the styrene copolymer is less than 1 part by mass, the thermal shrinkage of the film substrate may be deteriorated. On the other hand, if the styrene copolymer exceeds 50 parts by mass, the workability of the film substrate may be lost.

Although there is no restriction | limiting in particular in the manufacturing method of a styrene-type copolymer with a Vicat softening point of 100-130 degreeC, The block polymerization method, suspension polymerization method, solution polymerization method, and emulsion polymerization method can be employ | adopted suitably.

The Vicat softening point is measured by the following method.
Device name: Vicat softening point tester (for example, Toyo Seiki Co., Ltd., trade name: VSP tester)
Test piece: A test piece having a length of 30 mm, a width of 19 mm, and a thickness of 3.2 mm was molded by injection molding and then left in a constant temperature and humidity chamber at a temperature of 23 ° C. and a relative humidity of 50% for 24 hours to adjust the state.
Test method: Using a 5 kg weight, 50 ° C./hr. The temperature was raised at a temperature elevation rate of 1 mm, and the temperature when the indenter entered 1 mm into the test piece was measured. The test was performed three times, and the average value was defined as the Vicat softening point.

The styrenic resin in the film substrate of the present invention is a styrene homopolymer, a copolymer of styrene and a monomer copolymerizable with styrene, or styrene or styrene and its styrene in the presence of a rubbery polymer. Those obtained by (co) polymerizing one or more monomers copolymerizable with styrene are preferred. Monomers copolymerizable with styrene include α-substituted styrenes such as α-methylstyrene; aromatic ring-substituted styrenes such as vinyltoluene, t-butylstyrene, chlorostyrene, bromostyrene, dibromostyrene, and tribromostyrene. ; Vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; acrylic esters such as methyl acrylate and ethyl acrylate; methacrylic esters such as methyl methacrylate and ethyl methacrylate; vinyl carboxyls such as acrylic acid and methacrylic acid; Acids; unsaturated carboxylic acid amides such as acrylic amide and methacrylic acid amide; unsaturated dicarboxylic imide derivatives such as maleimide, N-phenylmaleimide and N-cyclohexylmaleimide; unsaturated dicarboxylic acids such as maleic acid, itaconic acid and citraconic acid Examples include rubonic acid anhydride. However, it is not limited to these.

The styrenic resin is not particularly limited, and a commonly used known resin can be used. Specifically, a polystyrene resin called GPPS and / or a rubber-reinforced polystyrene resin called HIPS can be used. Among these, a polystyrene resin or a mixture of a polystyrene resin and a rubber-reinforced polystyrene resin that can easily adjust the film strength by controlling the molecular weight is preferable.

The blending amount of the styrene resin in the film substrate of the present invention is 1 to 60 parts by mass, preferably 10 to 40 parts by mass with respect to 100 parts by mass of the aromatic vinyl elastomer. When the styrene-based resin is less than 1 part by mass, the strength of the film substrate is low and the film is easily stretched. On the other hand, when the styrene-based resin exceeds 60 parts by mass, the workability of the film base material is lost, and the film base material becomes rigid and pinhole resistance may be lowered.

（式中、ｎは１〜１００の整数、Ｒ_１、Ｒ_２、はそれぞれ独立にＣ１−２４のアルキル基を表す。）

（式中、ｎは１〜１００の整数、Ｒ_１、Ｒ_２、はそれぞれ独立にＣ１−２４のアルキル基を表す。） The hindered amine stabilizer in the film substrate of the present invention has at least one molecular skeleton selected from the following general formulas (Chemical Formula 5) and (Chemical Formula 6), and is included in the styrenic copolymer. The structure does not react with the ethylenically unsaturated carboxylic acid. Other than this structure, an acid-base reaction is caused with the ethylenically unsaturated carboxylic acid contained in the styrene copolymer, and the processability of the film substrate is deteriorated.

(In the formula, n is an integer of 1 to 100, and R ₁ and R ₂ each independently represents a C1-24 alkyl group.)

(In the formula, n is an integer of 1 to 100, and R ₁ and R ₂ each independently represents a C1-24 alkyl group.)

The blending amount of the hindered amine stabilizer in the film substrate of the present invention is 0.01 to 5 parts by weight, preferably 0.01 to 2 parts by weight with respect to 100 parts by weight of the aromatic vinyl elastomer. When the hindered amine stabilizer is less than 0.01 parts by mass, the weather resistance of the pressure-sensitive adhesive tape obtained from the film substrate is insufficient. On the other hand, when the amount of the hindered amine stabilizer exceeds 5 parts by mass, a pinhole is generated during the processing of the film substrate, and the processability is lost.

The acid dissociation index pKa value of the hindered amine stabilizer measured in an aqueous solution at 25 ° C. is preferably 6.5 or less. If the acid dissociation index pKa value exceeds 6.5, an acid-base reaction may occur with the ethylenically unsaturated carboxylic acid contained in the styrene copolymer, which may cause a problem in the workability of the film substrate.

The film base material of the present invention preferably contains an inorganic filler. The reason for blending inorganic fillers is to improve the hand cutting property of the film base material, while increasing the heat conduction during the molding process to increase the cooling effect of the film base material and to suppress the distortion generated in the film base material. Because. The average particle diameter of the inorganic filler is, for example, 20 μm or less, preferably 10 μm or less. When the average particle diameter exceeds 20 μm, the tensile strength and breaking elongation of the film base material may be lowered, and the flexibility may be lowered and pinholes may be generated. The average particle diameter is a value based on particle distribution measurement by a laser diffraction method. As a particle distribution measuring machine, for example, there is a product name “Model LS-230” manufactured by Beckman Coulter, Inc. Moreover, when an inorganic filler is blended as a non-halogen flame retardant, char (carbonized layer) can be formed and the flame retardancy of the film substrate can be improved.

Examples of inorganic fillers include aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, calcium hydroxide, potassium hydroxide, barium hydroxide, triphenyl phosphite, ammonium polyphosphate, polyphosphate amide, zirconium oxide and magnesium oxide. , Zinc oxide, titanium oxide, molybdenum oxide, guanidine phosphate, hydrotalcite, snakerite, zinc borate, anhydrous zinc borate, zinc metaborate, barium metaborate, antimony oxide, antimony trioxide, antimony pentoxide, red phosphorus, Talc, alumina, silica, boehmite, bentonite, sodium silicate, calcium silicate, calcium sulfate, calcium carbonate, and magnesium carbonate, and one or more compounds selected from these are used. In particular, the use of at least one selected from the group consisting of aluminum hydroxide, magnesium hydroxide, hydrotalcite, and magnesium carbonate is excellent in flame retardancy and is economically advantageous.

The blending amount of the inorganic filler is preferably 1 to 300 parts by mass, particularly preferably 5 to 100 parts by mass with respect to 100 parts by mass of the aromatic vinyl elastomer. If the inorganic filler exceeds 300 parts by mass, mechanical properties such as moldability and strength of the film substrate may be inferior.

Moreover, a stabilizer, such as a coloring agent, an antioxidant, a ultraviolet absorber, and a lubricant, and other additives can be blended with the film base as needed, as long as the effects of the present invention are not impaired.

The means for forming the film substrate is not particularly limited, but the above-mentioned various materials can be mixed with conventional melt-kneading and various mixing devices (for example, a single or twin screw extruder, roll, Banbury mixer, various kneaders, etc. ) Are mixed so that each component is uniformly dispersed, and the resulting mixture is formed into a film by a conventional forming method (eg, T-die method, inflation method, calendar method). Among these, a calendar molding machine is preferable. As the roll arrangement method in calendar molding, for example, a known method such as L-type, reverse L-type, and Z-type can be adopted, and the roll temperature is usually set in the range of 150 to 200 ° C, preferably 160 to 190 ° C. . The formed film is cut to a desired tape width.

The thickness in particular of a film base material is not restrict | limited, For example, it is 40-500 micrometers, Preferably it is 70-300 micrometers, More preferably, it is 80-160 micrometers. In addition, the film base material may have a single layer form or may have a multiple layer form. For example, in order to cope with the operation of winding an adhesive tape around an electric wire having various forms, the winding workability may be reduced when the thickness of the film substrate is increased.

By irradiating the film base material with an electron beam and crosslinking, the film base material can be prevented from being deformed or contracted when placed under a high temperature, and the temperature dependency can be reduced. In this case, the irradiation amount of the electron beam is preferably 10 to 150 Mrad, particularly preferably 15 to 25 Mrad. If the irradiation amount is less than 10 Mrad, the temperature dependency may not be improved. On the other hand, when the irradiation amount exceeds 150 Mrad, the film base material is deteriorated by the electron beam, which may cause a problem in workability in post-processing.

A cross-linking agent for promoting electron beam cross-linking may be added. Specific examples of the crosslinking agent include low molecular weight compounds and oligomers having at least two carbon-carbon double bonds in the molecule, such as acrylate compounds, urethane acrylate oligomers, and epoxy acrylate oligomers.

An adhesive layer may be formed on one side of the film substrate. As a pressure-sensitive adhesive for constituting the pressure-sensitive adhesive layer, a commonly used pressure-sensitive adhesive can be appropriately used. For example, a rubber-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, or the like can be used. Moreover, in order to make these pressure-sensitive adhesives have desirable performance, tackifiers, anti-aging agents, and further curing agents for pressure-sensitive adhesives can be blended.

Base polymers for rubber adhesives include natural rubber, recycled rubber, silicone rubber, isoprene rubber, styrene butadiene rubber (SBR), polyisoprene, nitrile butadiene rubber (NBR), styrene-isoprene copolymer, styrene-isoprene Butadiene copolymers are preferred.

A crosslinking agent, a softening agent, a filler, a flame retardant, etc. can be added to a rubber-type adhesive as needed. Specific examples include isocyanate crosslinking agents as crosslinking agents, liquid rubber as softening agents, calcium carbonate as fillers, and inorganic flame retardants such as magnesium hydroxide and red phosphorus as flame retardants.

Examples of the acrylic pressure-sensitive adhesive include a homopolymer of (meth) acrylic acid ester or a copolymer with a copolymerizable monomer. (Meth) acrylic acid ester or copolymerizable monomer includes (meth) acrylic acid alkyl ester (for example, methyl ester, ethyl ester, butyl ester, 2-ethylhexyl ester, octyl ester, etc.), (meth) acrylic acid glycidyl ester , (Meth) acrylic acid, itaconic acid, maleic anhydride, (meth) acrylic acid amide, (meth) acrylic acid N-hydroxyamide, (meth) acrylic acid alkylaminoalkyl ester (for example, dimethylaminoethyl methacrylate, t- Butylaminoethyl methacrylate), vinyl acetate, styrene, acrylonitrile and the like. Of these, as the main monomer, an alkyl acrylate ester whose homopolymer (homopolymer) usually has a glass transition temperature of −50 ° C. or lower is preferred.

The tackifier resin used for the tackifier can be selected in consideration of the softening point, compatibility with each component, and the like. Examples include terpene resins, rosin resins, hydrogenated rosin resins, coumarone / indene resins, styrene resins, aliphatic and alicyclic petroleum resins, terpene-phenol resins, xylene resins, and other aliphatic carbonizations. Examples thereof include a hydrogen resin or an aromatic hydrocarbon resin. The softening point of the tackifying resin is preferably 65 to 170 ° C, particularly preferably 80 to 150 ° C. Furthermore, an alicyclic saturated hydrocarbon resin of a petroleum resin having a softening point of 65 to 130 ° C, a polyterpene resin having a softening point of 80 to 130 ° C, a glycerin ester of a hydrogenated rosin having a softening point of 80 to 130 ° C, and the like are more preferable. These can be used either alone or in combination.

Anti-aging agents are used to improve rubber adhesives because unsaturated double bonds in rubber molecules tend to deteriorate in the presence of oxygen and light.

Examples of the anti-aging agent include phenolic anti-aging agents, amine-based anti-aging agents, benzimidazole-based anti-aging agents, dithiocarbamate-based anti-aging agents, phosphorous anti-aging agents and the like alone or as a mixture. it can.

Examples of the curing agent for the pressure-sensitive adhesive include isocyanate-based, epoxy-based, and amine-based adhesives for acrylic pressure-sensitive adhesives, and may be a mixture of these alone or a mixture thereof.

Specific examples of the isocyanate curing agent include polyvalent isocyanate compounds such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, and diphenylmethane. -4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, Examples include lysine isocyanate.

The coating means on the film substrate such as the pressure-sensitive adhesive, pressure-sensitive adhesive imparting agent and anti-aging agent constituting the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape is not particularly limited. For example, the pressure-sensitive adhesive, the pressure-sensitive adhesive imparting agent and There is a method in which a pressure-sensitive adhesive solution comprising an anti-aging agent is applied to one side of the film substrate by a transfer method and dried. Although the thickness after drying of an adhesive layer can be suitably selected in the range which does not impair adhesiveness or handleability, the thickness of an adhesive layer is 5-100 micrometers, for example, Preferably it is 10-50 micrometers. When it is thinner than 5 μm, the adhesive force and the unwinding force may be lowered. On the other hand, when it becomes thicker than 100 μm, the coating performance may be deteriorated.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. Further, various evaluations in the examples are values and evaluations measured as follows, and the results are shown in Tables 1 and 2.

In Tables 1 and 2, “flexibility” refers to the tensile strength and elongation at break of 25% modulus measured in accordance with JIS C 2107. In an evaluation test chamber set at a temperature of 23 ± 2 ° C. and a humidity of 50 ± 5% RH, the pressure-sensitive adhesive tape to be tested showed a measured value of n = 3 or more and was evaluated according to the following evaluation criteria.
Good: Modulus tensile strength of 5.0 to 15.0 N / mm ² and tensile elongation at break of 100 to 400%.
Poor: less than ² tensile strength 5.0 N / mm in modulus, 15.0 N / mm ^2, or greater than the tensile elongation at break is less than 100%, 400% more than those.

In Tables 1 and 2, “hand cutting property” means that the adhesive tape formed to a length of 100 mm is cut by a human hand in the lateral direction, the state of the cut surface of the adhesive tape is visually determined, Evaluation was based on the evaluation criteria.
Good: The cut surface of the adhesive tape has been cut cleanly.
Defect: The cut end of the cut surface of the pressure-sensitive adhesive tape extends and further cuts in the flow direction of the pressure-sensitive adhesive tape.

In Tables 1 and 2, “Heat resistance” means an evaluation test in which a 100 mm long film is allowed to stand in an atmosphere of 100 ° C. for 10 minutes and then set to a temperature of 23 ± 2 ° C. and a humidity of 50 ± 5% RH. These are shrinkage rates of MD (longitudinal direction of calendered film) and TD (lateral direction of calendered film) after standing in the room for 20 minutes or more. An average value of measured values of n = 3 or more is shown and evaluated according to the following evaluation criteria.
Good: Shrinkage is less than 10%.
Poor: The shrinkage rate is 10% or more.

In Tables 1 and 2, “Abrasion resistance” means that a Kanakin No. 3 cotton cloth is placed on a film substrate having a length of 100 mm and a width of 50 mm as a wear material, and a weight of 500 g is placed on the cotton cloth. The degree of scratching of the film base material after rubbing the film base material and the wear material at the reciprocating speed for 60 minutes was visually determined and evaluated according to the following evaluation criteria.
Good: No damage to the film substrate.
Defect: The film substrate has scratches.

In Tables 1 and 2, “weather resistance” means that the film substrate was subjected to an accelerated deterioration test under the conditions of no rain and a black panel temperature of 63 ° C. with a sunshine weather meter, and rupture after irradiation for 400 hours relative to rupture elongation before irradiation. The elongation retention was evaluated according to the following evaluation criteria.
Good: Break elongation retention rate of 80% or more.
Defect: The elongation at break retention is less than 80%.

In Tables 1 and 2, “base material processability” was evaluated by the following evaluation criteria for roll adhesiveness and amount of occurrence of blisters in calendar molding. The roll adhesiveness is formed by calendering at a roll temperature of 150 to 200 ° C. for 10 minutes and visually checked for the presence or absence of adhesion. As for the amount of generated defects, a 30 cm square test piece is prepared from a film base material obtained by calendering, and the number of irregularities having a diameter of 0.5 mm or more is visually measured.
Good: No sticking to the roll and 10 or less occurrences of fluff.
Defective: No sticking to the roll, but with more than 10 bumps or sticking to the roll.

Example 1
The blending of the film base material in this example is 100 parts by mass of a completely hydrogenated styrene-butadiene random copolymer (SOE SS9000 manufactured by Asahi Kasei Chemicals Co., Ltd.) as an aromatic vinyl elastomer, and a styrene-based elastomer. T-080 manufactured by Toyo Styrene Co., Ltd. as a copolymer (Vicat softening point 115 ° C .: 92% by mass of aromatic vinyl monomer, 8% by mass of ethylenically unsaturated carboxylic acid), polystyrene (Toyo Styrene) as a styrene resin 30 parts by mass of GPPS G-14L), 0.1 part by mass of Tinuvin XT850FF (pKa value 6.5) manufactured by Chiba Gaigi Co., Ltd. as a hindered amine stabilizer, and magnesium hydroxide having an average particle diameter of 5.0 μm as an inorganic filler (Magsees N-1 manufactured by Kamishima Chemical Industry Co., Ltd.) 30 parts by mass, phosphate ester lubricant (Sakai Chemical Co., Ltd. H-933D-3) 0.5 parts by weight, the black colorant (manufactured by Dainippon Ink & Chemicals, Inc. F-30940MM) is 3 parts by weight. These materials are mixed using a Banbury mixer so that each component is uniformly dispersed, and then formed into a thickness of about 0.1 mm (100 μm) at a roll temperature of 160 ° C. by a calendering machine. Got. Next, a rubber adhesive composed of a mixture of natural rubber and SBR is applied to the film substrate by a comma direct method, and after a drying process, an adhesive layer is formed with a thickness of 20 μm on one side of the film substrate. The adhesive tape was obtained by cutting into a 25 mm tape.

(Example 2)
A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that 0.1 part by mass of the hindered amine stabilizer of Example 1 (Tinubin XT850FF manufactured by Ciba-Gaigi Co., Ltd.) was changed to 4 parts by mass.

(Example 3)
A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that a hindered amine stabilizer represented by the following chemical formula (chemical formula 7) having a pKa of 4.5 was used.

Example 4
An adhesive tape was obtained in the same manner as in Example 1 except that 0.1 part by mass of the hindered amine stabilizer of Example 3 was changed to 4 parts by mass.

(Example 5)
Except that the aromatic vinyl elastomer is 100 parts by mass of a completely hydrogenated product of styrene-butadiene block copolymer (Kuraray Septon 8007) and the styrene resin is 30 parts by mass (HIPS E640N manufactured by Toyo Styrene Co., Ltd.) An adhesive tape was obtained in the same manner as in Example 1.

(Example 6)
15 parts by mass of a styrene resin (GPPS G-14L manufactured by Toyo Styrene Co., Ltd.) and a styrene copolymer (T-080 manufactured by Toyo Styrene Co., Ltd., Vicat softening point 115 ° C .: 92% by mass of an aromatic vinyl monomer, ethylenic An adhesive tape was obtained in the same manner as in Example 1 except that the unsaturated carboxylic acid (8% by mass) was 5 parts by mass.

(Example 7)
A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that magnesium hydroxide was not blended as the inorganic filler.

(Comparative Example 1)
Example 1 except that the hindered amine stabilizer of Example 1 represented by the following chemical formula (Chemical Formula 8: hydrogen bonded directly to the nitrogen of the hindered amine) was used as Tinuvin XT770DF (pKa value 8.8 manufactured by Ciba-Gaigi Japan) In the same manner as in No. 1, an adhesive tape was obtained. In Comparative Example 1, adhesion to the roll occurred during calendar molding, and it was difficult to produce a substrate.

(Comparative Example 2)
The hindered amine stabilizer of Example 1 was the same as that of Example 1 except that the hindered phenol stabilizer represented by 2,6-di-t-butyl-4-methylphenol was used. To obtain an adhesive tape. In Comparative Example 2, adhesion to the roll occurred during calendar molding, and it was difficult to produce a substrate, and weather resistance could not be obtained.

(Comparative Example 3)
An adhesive tape was obtained in the same manner as in Example 1 except that the amount of the hindered amine stabilizer in Example 1 was 0.005 part by mass. In Comparative Example 3, the weather resistance was not obtained.

(Comparative Example 4)
An adhesive tape was obtained in the same manner as in Example 1 except that the amount of the hindered amine stabilizer in Example 1 was changed to 10 parts by mass. In Comparative Example 4, substrate processability was not obtained.

(Comparative Example 5)
In Comparative Example 6 in which the film base composition of Example 1 was 100 parts by mass of LDPE (manufactured by Tosoh Corporation, Petrocene 226), elongation, hand cutting properties, and abrasion resistance were not obtained.

As is apparent from Tables 1 and 2, according to the present invention, the film substrate having the properties of flexibility, hand cutting, heat resistance, wear resistance, weather resistance, and substrate workability in a well-balanced manner, and the film It turns out that the adhesive tape using a base material is obtained easily.

The pressure-sensitive adhesive tape using the film substrate of the present invention can be suitably used, for example, as a binding tape that binds electric wires and cables such as automobile wire harnesses.

Claims (4)

At least one selected from the group consisting of a styrene-butadiene random copolymer, a styrene-butadiene block copolymer, a hydrogenated styrene-butadiene random copolymer, and a hydrogenated styrene-butadiene block copolymer. A styrene-based copolymer comprising 80 to 99% by mass of an aromatic vinyl monomer and 1 to 20% by mass of an ethylenically unsaturated carboxylic acid monomer that is methacrylic acid with respect to 100 parts by mass of a certain aromatic vinyl elastomer. and 1 to 50 parts by weight, and a styrene-based resin 1 to 60 parts by weight polystyrene resin (GPPS) and / or rubber reinforced polystyrene resin (HIPS), met film substrate containing the following general formula (formula 1), (Formula 2) has at least one molecular scaffold is selected from der acid dissociation exponent pKa value of 6.5 or less It hindered amine stabilizer, adhesive tape to form an adhesive layer on one surface of the film substrate containing 0.01 to 5 parts by weight per 100 parts by weight aromatic vinyl-based elastomer.

(In the formula, n is an integer of 1 to 100, and R ₁ and R ₂ each independently represents a C1-24 alkyl group.)

(In the formula, n is an integer of 1 to 100, and R ₁ and R ₂ each independently represents a C1-24 alkyl group.) The pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed on one side of the film substrate used in claim 1 , wherein the styrene copolymer has a Vicat softening point of 100 to 130 ° C. The adhesive tape which formed the adhesive layer on the single side | surface of the film base material used by Claim 1 or 2 containing 1-300 mass parts of inorganic fillers with respect to 100 mass parts of aromatic vinyl-type elastomers . An adhesive tape for bundling using the adhesive tape according to claim 3 .