JPWO2005082953A1 - Modified petroleum resin emulsion and acrylic pressure-sensitive adhesive composition using the same - Google Patents

Abstract

The present invention comprises 10 to 100% by mass of an olefinically unsaturated hydrocarbon monomer unit having 4 to 6 carbon atoms and 0 to 90% by mass of an olefinically unsaturated hydrocarbon monomer unit having 7 to 11 carbon atoms, A modified petroleum resin emulsion comprising a modified petroleum resin having a softening point of 30 ° C. or higher and an acid value of 0.1 to 100 KOHmg / g, excellent in peel adhesion to a polyolefin resin adherend, and initial An acrylic pressure-sensitive adhesive composition having an excellent balance between adhesion and holding power, and a modified petroleum resin emulsion suitable as a tackifier for the pressure-sensitive adhesive composition are provided.

Description

  The present invention relates to a modified petroleum resin emulsion and an acrylic pressure-sensitive adhesive composition using the same, and more specifically, particularly excellent in peel adhesion to a polyolefin resin adherend, and in the balance between initial adhesive force and holding force. The present invention also relates to an excellent acrylic pressure-sensitive adhesive composition and a modified petroleum resin emulsion suitable as a tackifier for the pressure-sensitive adhesive composition.

  An aqueous pressure-sensitive adhesive composition mainly composed of an acrylic polymer emulsion is widely used because it is colorless and transparent, excellent in aging resistance, and hardly causes environmental problems due to volatilization of an organic solvent. Such acrylic pressure-sensitive adhesive compositions are usually rosin-based tackifying resins, terpene-based tackifying resins, and petroleum resin-based pressure-sensitive adhesives for the purpose of improving the adhesive properties such as peel adhesive strength, initial adhesive strength and holding power. A tackifying resin such as an imparting resin is blended.

  For example, Patent Document 1 discloses a petroleum resin containing 10 to 60% by mass of an aromatic vinyl monomer unit such as styrene or α-methylstyrene in an acrylic polymer emulsion and having a softening point of 10 to 120 ° C. An aqueous acrylic pressure-sensitive adhesive composition containing an emulsion consisting of Patent Document 2 discloses a tackifying resin obtained by partially hydrogenating an aromatic ring of an aromatic hydrocarbon resin obtained by polymerizing a C9 fraction such as vinyltoluene or indene with an acrylic polymer emulsion. An aqueous acrylic pressure-sensitive adhesive composition containing an emulsion consisting of However, the pressure-sensitive adhesive composition as described above is inferior in peel adhesion to a nonpolar adherend such as polyethylene.

  Furthermore, in Patent Document 3, 3 to 45 parts by mass of a liquid tackifier resin and a crosslinking agent are blended with respect to 100 parts by mass of a solid content of an acrylic polymer emulsion having a glass transition temperature of −60 to −30 ° C. An aqueous acrylic pressure-sensitive adhesive composition is disclosed. However, such a pressure-sensitive adhesive composition has poor holding power.

JP-A 61-275363 JP-A-9-188864 JP 2000-319618 A

In view of the above circumstances, an object of the present invention is an acrylic pressure-sensitive adhesive composition excellent in peel adhesion to a polyolefin-based resin adherend and excellent in the balance between initial adhesive force and holding power, and the pressure-sensitive adhesive composition Another object of the present invention is to provide a modified petroleum resin emulsion suitable as a tackifier.
As a result of intensive studies to achieve the above object, the present inventors have found that the olefinically unsaturated hydrocarbon monomer unit having 4 to 6 carbon atoms is 10 to 100% by mass and the olefinic hydrocarbon having 7 to 11 carbon atoms. When a modified petroleum resin emulsion comprising a modified petroleum resin comprising a saturated hydrocarbon monomer unit of 0 to 90% by mass and having a specific softening point and an acid value is used, peel adhesion to a polyolefin resin adherend In addition, it was found that an acrylic pressure-sensitive adhesive composition excellent in the initial adhesive force and holding force balance was obtained, and the present invention was completed based on this finding.
Thus, according to the present invention, 10 to 100% by mass of olefinically unsaturated hydrocarbon monomer units having 4 to 6 carbon atoms and 0 to 90 masses of olefinically unsaturated hydrocarbon monomer units having 7 to 11 carbon atoms. %, A modified petroleum resin emulsion comprising a modified petroleum resin having a softening point of 30 ° C. or higher and an acid value of 0.1 to 100 KOH mg / g is provided.
Moreover, according to this invention, the acrylic adhesive composition containing an acrylic polymer emulsion and the said modified | denatured petroleum resin emulsion is provided.
Furthermore, according to this invention, the adhesive tape formed by apply | coating the said acrylic adhesive composition on a base | substrate is provided.

Hereinafter, the present invention will be described in detail.
(Modified petroleum resin emulsion)
The modified petroleum resin emulsion of the present invention is composed of 10 to 100% by mass of olefinically unsaturated hydrocarbon monomer units having 4 to 6 carbon atoms and 0 to 90 olefinically unsaturated hydrocarbon monomer units having 7 to 11 carbon atoms. A modified petroleum resin comprising a mass%, having a softening point of 30 ° C. or higher and an acid value of 0.1 to 100 KOH mg / g.

  The modified petroleum resin is an olefinically unsaturated hydrocarbon monomer unit having 4 to 6 carbon atoms, preferably 10 to 100 mass%, preferably 40 to 95 mass%, more preferably 50 to 85 mass%, and 7 to 7 carbon atoms. 11 olefinically unsaturated hydrocarbon monomer units of 0 to 90% by mass, preferably 5 to 60% by mass, more preferably 15 to 50% by mass. When there is little content of a C4-C6 olefinically unsaturated hydrocarbon monomer unit, it is inferior to the peeling adhesive force with respect to a polyolefin resin adherend, and initial adhesive force also falls. A modified petroleum resin containing an olefinically unsaturated hydrocarbon monomer unit having 7 to 11 carbon atoms is preferred from the viewpoint that the peel adhesive strength and retention strength for the polyolefin resin adherend can be further enhanced.

Examples of the olefinically unsaturated hydrocarbon monomer having 4 to 6 carbon atoms used as a raw material include monoolefinically unsaturated hydrocarbon and diolefinically unsaturated hydrocarbon having 4 to 6 carbon atoms.
Examples of monoolefinic unsaturated hydrocarbons having 4 to 6 carbon atoms include chain monoolefins such as isobutene, 1-butene, 2-butene, 1-pentene, 2-pentene, methylbutene, methylpentene, and hexene; cyclopentene , Cyclic monoolefins such as methylcyclopentene and cyclohexene;

  Examples of the diolefinically unsaturated hydrocarbon monomer having 4 to 6 carbon atoms include chain conjugated dienes such as 1,3-butadiene, isoprene, 1,3-pentadiene, 1,3-hexadiene; cyclopentadiene, And cyclic conjugated dienes such as methylcyclopentadiene; non-conjugated dienes such as 1,2-butadiene and 1,4-pentadiene;

  The amount of the olefinically unsaturated hydrocarbon monomer having 4 to 6 carbon atoms used in producing the modified petroleum resin is preferably 10% by weight or more, more preferably 45 to 95% by weight based on the total amount of the monomers. %, Particularly preferably 55 to 85% by mass. If this amount is too small, the peel adhesion to the polyolefin resin adherend is inferior and the initial adhesion is also reduced.

  The ratio of the monoolefinically unsaturated hydrocarbon monomer having 4 to 6 carbon atoms and the diolefinically unsaturated hydrocarbon monomer having 4 to 6 carbon atoms is a mass ratio, preferably 20/80 to 80 /. 20, more preferably 30/70 to 70/30, particularly preferably 35/65 to 65/35.

  In the present invention, it is preferable to use a C 4-6 diolefinically unsaturated hydrocarbon containing isoprene and / or 1,3-pentadiene in an amount of 70% by mass or more, more preferably 90% by mass or more.

Examples of the olefinically unsaturated hydrocarbon monomer having 7 to 11 carbon atoms that are optionally used as a raw material include aromatic vinyl monomers such as styrene, α-methylstyrene, p-methylstyrene, ethylstyrene, and t-butylstyrene. A chain monoolefin having 7 to 11 carbon atoms such as 2,4,4-trimethyl-1-pentene, 2,4,4-trimethyl-2-pentene, heptene, octene; methylcyclohexene, dicyclopentadiene, Examples thereof include cyclic olefins having 7 to 11 carbon atoms such as indene and coumarone. Of these, aromatic vinyl monomers are preferable, and styrene is more preferably used.
The amount of the olefinically unsaturated hydrocarbon monomer having 7 to 11 carbon atoms in producing the modified petroleum resin is preferably 90% by mass or less, more preferably 5 to 55% by mass with respect to the total amount of the monomer. %, Particularly preferably 15 to 45% by mass. When it is used in the above range, an acrylic pressure-sensitive adhesive composition that is superior in peel adhesion and holding power to a polyolefin resin adherend can be obtained.

  The softening point of the modified petroleum resin is 30 ° C. or higher, preferably 50 to 130 ° C., more preferably 80 to 120 ° C. When the softening point is less than 30 ° C., the pressure-sensitive adhesive composition is inferior in holding power.

  The acid value of the modified petroleum resin is 0.1 to 100 KOH mg / g, preferably 0.3 to 50 KOH mg / g, more preferably 1 to 20 KOH mg / g. Whether the acid value is low or high, the peel adhesion to the polyolefin resin adherend is poor.

  The weight average molecular weight of the modified petroleum resin is preferably in the range of 1,000 to 4,000, more preferably 1,500 to 3,500. When the weight average molecular weight is in the above range, an acrylic pressure-sensitive adhesive composition that is superior in peel adhesion and holding power to a polyolefin resin adherend can be obtained.

  The modified petroleum resin is usually obtained by cationic polymerization of the monomer in a polymerization solvent using an acidic metal halide catalyst to obtain a petroleum resin, and then the resulting petroleum resin is ethylenically unsaturated. It can be obtained by addition reaction of carboxylic acid.

The polymerization solvent is not particularly limited as long as it does not inhibit the polymerization reaction. For example, aliphatic hydrocarbons such as pentane, hexane, heptane, cyclopentane, cyclohexane, isopentane, methylpentane; benzene, toluene, xylene, etc. Aromatic hydrocarbons; and the like. These polymerization solvents can be used alone or in combination of two or more.
The usage-amount of a polymerization solvent is 40-200 mass parts normally with respect to 100 mass parts of monomer whole quantity, Preferably it is 60-100 mass parts.

The acidic metal halide catalyst used as the polymerization catalyst is not particularly limited as long as it is a Friedel Crafts type catalyst. Typical examples thereof include fluorides, chlorides, bromides and iodides of metals such as aluminum, boron and iron. Of these, aluminum halides such as aluminum chloride and aluminum bromide are preferable, and aluminum chloride can be more preferably used.
The usage-amount of an acidic metal halide catalyst is 0.1-10 mass% normally with respect to the monomer whole quantity, Preferably it is 0.5-5 mass%.

  In the polymerization, it is preferable to contact the acidic metal halide catalyst and the cyclic monoolefin in advance. As this cyclic monoolefin, a C5-C6 cyclic monoolefin is preferable, and cyclopentene can be used more preferably. The amount of cyclic monoolefin used here is preferably at least 5 times the amount of the acid metal halide catalyst.

A conventionally known method can be employed as the polymerization operation.
The polymerization temperature is usually in the range of -20 ° C to 100 ° C, preferably 0 ° C to 80 ° C.

  After the polymerization reaction is started, when a predetermined polymerization conversion rate is reached, a polymerization terminator is added to stop the polymerization reaction. The polymerization conversion rate when stopping the polymerization reaction is usually 50 to 95% by mass, preferably 60 to 90% by mass.

  After stopping the polymerization reaction, the unreacted monomer and the polymerization solvent are distilled off, and, if desired, a petroleum resin is obtained by removing the low molecular weight oligomer component by steam distillation at high temperature.

Next, the obtained petroleum resin is subjected to an addition reaction with an ethylenically unsaturated carboxylic acid to modify the petroleum resin.
Examples of the ethylenically unsaturated carboxylic acid include ethylenically unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid; ethylenically unsaturated polyvalent carboxylic acids such as maleic acid, fumaric acid, itaconic acid, and citraconic acid; maleic anhydride And ethylenically unsaturated polyvalent carboxylic acid anhydrides such as itaconic anhydride; partial esters of ethylenically unsaturated polyvalent carboxylic acids such as monomethyl maleate and monoethyl fumarate; Among these, an ethylenically unsaturated polyvalent carboxylic acid and an ethylenically unsaturated polyvalent carboxylic acid anhydride are preferable, an ethylenically unsaturated polyvalent carboxylic acid anhydride is more preferable, and maleic anhydride is particularly preferably used.

  The amount of the ethylenically unsaturated carboxylic acid used is preferably 0.01 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, particularly preferably 100 parts by weight of the petroleum resin obtained above. Is in the range of 0.5 to 5 parts by mass.

  The conditions for the addition reaction of the ethylenically unsaturated carboxylic acid are usually 50 to 300 ° C., preferably 200 to 270 ° C., preferably 5 minutes to 20 hours, more preferably 10 minutes to 3 hours. In addition, a diluent, an antigelling agent, a reaction accelerator and the like can be added as necessary during the addition reaction.

The modified petroleum resin emulsion of the present invention is obtained by emulsifying the modified petroleum resin obtained as described above in an aqueous medium.
As the aqueous medium, water is usually used, but an aqueous solution of a water-soluble organic solvent such as ethanol, ethylene glycol, or glycerin can also be used.
The usage-amount of an aqueous medium is 50-200 mass parts normally with respect to 100 mass parts of modified petroleum resins, Preferably it is 60-150 mass parts.

  The emulsification method is not particularly limited. For example, (1) a method in which a modified petroleum resin is wet-dispersed in an aqueous medium at a temperature lower than the softening point of the modified petroleum resin, and (2) a modified petroleum resin in an aqueous medium. A method of emulsifying the modified petroleum resin in a state heated to a temperature at which the fluidized fluid is fluidized, (3) a method of emulsifying the organic solvent solution of the modified petroleum resin in an aqueous medium, and (4) a temperature of fluidizing the fluid. (5) A method in which an aqueous medium is added to a modified petroleum resin that has been heated to a phase while emulsifying and phase inversion emulsification. (5) An aqueous medium is added to an organic solvent solution of the modified petroleum resin while stirring to Examples thereof include a phase emulsification method. Among these, the method (3) or (5) can be preferably employed in that the volume average particle diameter of the modified petroleum resin particles in the modified petroleum resin emulsion can be easily adjusted to a preferred range. When an organic solvent is used, it is preferable to distill off the organic solvent from the emulsion after emulsification.

  The method for emulsifying the modified petroleum resin of the present invention includes (a) high-pressure impact type (Gorin homogenizer: manufactured by Gorin), (b) rotor-stator method (Ebara Milder: manufactured by Ebara Seisakusho), (c) inside Shear (liquid-liquid shear) method (for example, Claremix, manufactured by M Technique Co., Ltd.), (d) stationary tube method (static mixer), (e) vertical stirring method, (f) line mill method, (g) vibration method, (H) Membrane emulsification type, (i) Centrifugal thin film contact type, etc. are mentioned. Among these, the method (a), (b) or (c) is preferable in that the volume average particle diameter of the modified petroleum resin particles in the modified petroleum resin emulsion is easily adjusted to a preferable range, and the method (a) is preferable. It can be particularly preferably employed.

The organic solvent for dissolving the modified petroleum resin is not particularly limited as long as it can dissolve the resin. For example, aromatic hydrocarbons such as benzene and toluene; aliphatic hydrocarbons such as pentane, hexane and heptane; And cycloaliphatic hydrocarbons such as cyclopentane and cyclohexane. Considering the safety in the emulsification step and the ease of distilling off the organic solvent, an organic solvent having a boiling point of 30 to 120 ° C. can be preferably used.
The solution concentration is usually 10 to 90% by mass, preferably 50 to 80% by mass.

In emulsification, it is preferable to use an emulsifier because the volume average particle diameter of the modified petroleum resin particles in the modified petroleum resin emulsion can be easily adjusted to a preferred range and the storage stability of the obtained modified petroleum resin emulsion is excellent.
The emulsifier is not particularly limited, and examples thereof include α-olefin sulfonated products, alkyl sulfates, alkyl phenyl sulfates, polyoxyethylene alkyl phenyl ether sulfates, polyoxyethylene alkyl phenyl ether sulfosuccinic acid half ester salts, and rosin soaps. Anionic emulsifiers; nonionic emulsifiers such as polyoxyethylene alkyl ethers and polyoxyethylene alkyl phenyl ethers.
The usage-amount of an emulsifier is about 1-10 mass parts normally with respect to 100 mass parts of modified petroleum resins, Preferably it is 1-5 weight part.

  The volume average particle diameter of the modified petroleum resin particles in the modified petroleum resin emulsion is preferably 0.1 to 1 μm, more preferably 0.2 to 0.6 μm. When the volume average particle size is in the above range, an acrylic pressure-sensitive adhesive composition that is superior in the balance of pressure-sensitive physical properties can be obtained.

The modified petroleum resin emulsion of the present invention preferably contains few modified petroleum resin particles having a particle diameter of 30 μm or more. When the number of particles having a particle diameter of 30 μm or more is too large, the surface of the pressure-sensitive adhesive composition becomes rough when the resulting pressure-sensitive adhesive composition is applied to a substrate, the appearance is deteriorated, and fish eyes are generated to form a uniform film. It may not be obtained, resulting in a product defect, and the peel adhesion may be reduced. The number of modified petroleum resin particles having a particle diameter of 30 μm or more can be measured by limiting to a specific particle diameter range using a precision particle size distribution measuring apparatus. The number of modified petroleum resin particles having a particle diameter of 30 μm or more is determined by measuring all the number of modified petroleum resin particles having a particle diameter in the range of 4 to 64 μm, and the modified petroleum resin particles having a particle diameter in the range of 30 to 64 μm. It is relatively evaluated as a ratio of the number of.
The ratio of the number of modified petroleum resin particles having a particle diameter of 30 μm or more in the modified petroleum resin particles in the particle diameter range of 4 to 64 μm is preferably 1% or less, more preferably 0.1% or less, It is more preferable that it is 0.05% or less, and it is particularly preferable that particles having a particle diameter of 30 μm or more do not exist.

  The method of setting the particle number distribution of the modified petroleum resin particles having a particle size of 4 to 64 μm in the above range is not particularly limited, and is a method of appropriately adjusting the conditions for emulsifying the modified petroleum resin, the particle size after emulsifying the modified petroleum resin. Examples thereof include a method of removing modified petroleum resin particles having a size of 30 μm or more. Conditions that are adjusted when emulsifying the modified petroleum resin include temperature, pressure, stirring strength, and the like, and these conditions are adjusted as necessary. As a method for removing modified petroleum resin particles having a particle diameter of 30 μm or more after emulsifying the modified petroleum resin, a method using a mesh filter to filter under its own weight or pressure, or a filtration device equipped with a membrane filter is used. The method of pressure filtration etc. are mentioned, It is preferable to pressurize and filter using a mesh filter at the point that a removal apparatus and operation are simple. The filtration operation can be repeated so that the number distribution of the modified petroleum resin particles having a particle diameter of 4 to 64 μm falls within the above range.

  The solid content concentration of the modified petroleum resin emulsion is preferably 30% by mass or more, more preferably 40 to 70% by mass.

  If necessary, the modified petroleum resin emulsion may further contain compounding agents such as an antifoaming agent, a thickening agent, a filler, an antioxidant, an antiseptic, and an antibacterial agent.

(Acrylic adhesive composition)
The acrylic pressure-sensitive adhesive composition of the present invention contains an acrylic polymer emulsion and the modified petroleum resin emulsion.

The acrylic polymer constituting the acrylic polymer emulsion contains a (meth) acrylic acid alkyl ester monomer unit as a main component.
Examples of the (meth) acrylic acid alkyl ester monomer include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic acid 2- And ethyl hexyl. These monomers can be used alone or in combination.
The acrylic polymer may be a copolymer of a (meth) acrylic acid alkyl ester monomer and another monomer copolymerizable therewith.
Examples of other monomers copolymerizable with the (meth) acrylic acid alkyl ester monomer include (meth) acrylic acid, (meth) acrylic acid glycidyl, (meth) acrylic acid 2-hydroxyethyl, N- Examples include methylol (meth) acrylamide, (meth) acrylonitrile, vinyl acetate, and styrene.

  The glass transition temperature of the acrylic polymer is not particularly limited, but is usually −80 to 0 ° C., preferably −60 to −10 ° C. If the glass transition temperature is too high, the initial adhesive force tends to decrease, while if too low, the holding force tends to decrease.

  The acrylic polymer emulsion is usually produced by emulsion polymerization of the above monomers. The method for emulsion polymerization is not particularly limited, and conventionally known methods can be employed.

  The volume average particle diameter of the acrylic polymer particles in the acrylic polymer emulsion is not particularly limited, but is usually 0.05 to 1 μm, preferably 0.1 to 0.6 μm.

  The solid content concentration of the acrylic polymer emulsion is usually 40 to 70% by mass.

The acrylic pressure-sensitive adhesive composition of the present invention has a solid content of the modified petroleum resin emulsion, preferably 0.1 to 50 parts by mass, more preferably 2 to 100 parts by mass of the solid content of the acrylic polymer emulsion. 40 mass parts, Especially preferably, it contains 5-30 mass parts.
When the amount of the modified petroleum resin emulsion used is within the above range, a pressure-sensitive adhesive composition having excellent peel adhesion to the polyolefin resin adherend and excellent initial adhesion and holding power can be obtained.

  The acrylic pressure-sensitive adhesive composition further includes a plasticizer, a wax, an ultraviolet absorber, an antifoaming agent, a thickener, a filler, an antioxidant, an antiseptic, an antibacterial agent, a water-proofing agent, a A compounding agent such as a film auxiliary agent can be added. Moreover, the emulsion which consists of conventionally well-known tackifying resin can also be added in the range which does not inhibit the effect of this invention essentially.

(Adhesive tape)
The pressure-sensitive adhesive tape of the present invention is obtained by coating the above acrylic pressure-sensitive adhesive composition on a substrate.
Although it does not specifically limit as a base | substrate, For example, Papers, such as a craft paper, Japanese paper, a quality paper, a synthetic paper; Cloths, such as cotton cloth, a soft cloth, a polyester cloth; Cellophane, a polyester film, a polyamide film, a polyvinyl chloride film Resin films such as polypropylene film and polyethylene film; metal foils such as aluminum foil and copper foil; nonwoven fabrics such as polyester nonwoven fabric and rayon nonwoven fabric. These substrates may have a surface subjected to corona discharge treatment or a primer applied beforehand.
The thickness of the substrate is usually about 10 μm to 2 mm.

  As the coating apparatus, a conventionally known apparatus can be used, and for example, a die coater, a comma coater, a roll coater, or the like can be used.

  The coating amount of the acrylic pressure-sensitive adhesive composition is usually 1 to 200 μm, preferably 5 to 100 μm, in terms of the thickness after drying.

  After applying the acrylic pressure-sensitive adhesive composition on the substrate, the aqueous medium in the composition is volatilized to obtain a pressure-sensitive adhesive tape.

The pressure-sensitive adhesive tape of the present invention is particularly suitable as a pressure-sensitive adhesive tape for non-polar polyolefin-based resin products because it has excellent peel adhesion to non-polar polyolefin-based resin adherends. Of course, it can also be suitably used as an adhesive tape using a non-polar polyolefin resin as the substrate.
Here, the polyolefin resin mainly means a homopolymer or copolymer of an olefin monomer such as ethylene, propylene, butene, and isobutene. The polyolefin resin includes those having a very small amount of polar groups.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In Examples, “%” and “part” are all based on mass unless otherwise specified.

Evaluation was performed as follows.
(1) Styrene unit amount in resin (%): Determined by ¹ H-NMR analysis.
(2) Weight average molecular weight: It was determined as a standard polystyrene equivalent value by gel permeation chromatography.
(3) Softening point (° C.): Measured by the ring and ball method according to JIS K2531.
(4) Acid value (mgKOH / g): Measured according to JIS K0070.

(5) Volume average particle diameter of emulsion: measured using a light scattering particle diameter measuring instrument (LS-230: manufactured by Beckman Coulter, Inc.).
(6) Ratio of the number of modified petroleum resin particles of 30 μm or more: 0.1 g (solid content concentration: 50%) of a modified petroleum resin emulsion was added with 200 ml of an electrolytic solution (Isoton-II) and stirred to obtain a measurement sample. . Using a precision particle size distribution analyzer (Multisizer 3: manufactured by Beckman Coulter, Inc.), the number of modified petroleum resin particles having a particle diameter of 4 to 64 μm and a particle diameter of 30 μm or more was measured in increments of 2 μm. For the measurement, an aperture tube having a pore diameter of 140 μm was used.
The ratio of the number of modified petroleum resin particles having a particle diameter of 30 μm or more is represented by the ratio of the number of modified petroleum resin particles in the range of 30 to 64 μm in the modified petroleum resin particles in the range of particle diameter of 4 to 64 μm.
(7) Peel adhesive strength (N / m): Measured according to PSTC-1 (180 ° peel adhesion test by the adhesive tape committee (USA)) using polyethylene as an adherend at 23 ° C. The higher the value, the better.
(8) Holding power (minutes): Stainless steel is used as the adherend, and in accordance with PSTC-6 (holding force test method by the Adhesive Tape Committee (USA)), an adhesive tape with a width of 25 mm is used. The time (minutes) until peeling was measured at 25 × 25 mm, the load was 3.92 × 104 Pa, and the temperature was 50 ° C. The longer the time, the better.
(9) Initial adhesive strength (mm): The rolling ball tack was measured at 23 ° C. according to PSTC-6 (initial adhesive strength test method by the Adhesive Tape Committee (USA)). The smaller the value, the better.

(Synthesis Example 1)
After adding 86 parts of cyclopentane, 14 parts of cyclopentene, and 1 part of aluminum chloride to the reactor, the temperature was raised to 50 ° C. Subsequently, the remaining single unit consisting of 14 parts of cyclopentene, 44 parts of 1,3-pentadiene, 18 parts of styrene and 10 parts of a chain monoolefin having 4 to 6 carbon atoms (including 1-pentene, 2-butene, methylbutene, etc.). The polymerization was carried out while continuously adding the monomer mixture to the reactor over 60 minutes. Furthermore, after continuing reaction for 10 minutes at 50 degreeC, the mixture of methanol and aqueous ammonia was added to the reactor, and the polymerization reaction was stopped. The polymerization conversion rate at this time was 85%.
After the precipitate produced by the termination of polymerization was removed by filtration, the resulting polymer solution was charged into a distillation kettle and heated in a nitrogen atmosphere to remove the polymerization solvent and unreacted monomers. Next, the oligomer component having a low molecular weight was removed while blowing saturated water vapor at 240 ° C. or higher.

Next, 2.97 parts of maleic anhydride was added to 100 parts of the molten resin and subjected to an addition reaction at 230 ° C. for 1 hour. Then, 2,6-di-t-butyl-p- was used as an antioxidant. 0.3 parts of cresol was added and mixed.
Thereafter, the molten resin was taken out and allowed to cool to room temperature to obtain a modified petroleum resin A. The styrene unit amount, weight average molecular weight, softening point and acid value of the modified petroleum resin A were measured, and the results are shown in Table 1.

(Synthesis Example 2)
A modified petroleum resin B was obtained in the same manner as in Synthesis Example 1 except that the monomer composition and the amount of maleic anhydride shown in Table 1 were changed. The styrene unit amount, the weight average molecular weight, the softening point and the acid value of the modified petroleum resin B were measured, and the results are shown in Table 1.

(Synthesis Example 3)
After adding 86 parts of cyclopentane, 14 parts of cyclopentene, and 1 part of aluminum chloride to the reactor, the temperature was raised to 50 ° C. Subsequently, the remaining single unit consisting of 14 parts of cyclopentene, 44 parts of 1,3-pentadiene, 18 parts of styrene and 10 parts of a chain monoolefin having 4 to 6 carbon atoms (including 1-pentene, 2-butene, methylbutene, etc.). The polymerization was carried out while continuously adding the monomer mixture to the reactor over 60 minutes. Furthermore, after continuing reaction for 10 minutes at 50 degreeC, the mixture of methanol and aqueous ammonia was added to the reactor, and the polymerization reaction was stopped. The polymerization conversion rate at this time was 85%.
After the precipitate produced by the termination of polymerization was removed by filtration, the resulting polymer solution was charged into a distillation kettle and heated in a nitrogen atmosphere to remove the polymerization solvent and unreacted monomers. Subsequently, the low molecular weight oligomer component was removed while blowing saturated water vapor at 240 ° C. or higher.

  Next, 0.3 part of 2,6-di-t-butyl-p-cresol was added as an antioxidant to 100 parts of the molten resin and mixed. Thereafter, the molten resin was taken out and allowed to cool to room temperature to obtain petroleum resin C. The styrene unit amount, weight average molecular weight, softening point and acid value of petroleum resin C were measured, and the results are shown in Table 1.

(Synthesis Example 4)
After adding 86 parts of cyclopentane, 14 parts of cyclopentene, and 1 part of aluminum chloride to the reactor, the temperature was raised to 50 ° C. Subsequently, the remaining single unit consisting of 7 parts of cyclopentene, 22 parts of 1,3-pentadiene, 18 parts of styrene and a chain monoolefin having 4 to 6 carbon atoms (including 1-pentene, 2-butene, methylbutene, etc.). The polymerization was carried out while continuously adding the monomer mixture to the reactor over 60 minutes. Furthermore, after continuing reaction for 10 minutes at 50 degreeC, the mixture of methanol and aqueous ammonia was added to the reactor, and the polymerization reaction was stopped. The polymerization conversion rate at this point was 76%.
After the precipitate produced by the termination of polymerization was removed by filtration, the resulting polymer solution was charged into a distillation kettle and heated in a nitrogen atmosphere to remove the polymerization solvent and unreacted monomers.

Next, 3.49 parts of maleic anhydride was added to 100 parts of the molten resin and subjected to an addition reaction at 230 ° C. for 1 hour, and then 2,6-di-t-butyl-p-as an antioxidant. 0.3 parts of cresol was added and mixed.
Thereafter, the molten resin was taken out and allowed to cool to room temperature to obtain a modified petroleum resin D. The styrene unit amount, the weight average molecular weight, the softening point and the acid value of the modified petroleum resin D were measured, and the results are shown in Table 1.

Example 1
An aqueous solution obtained by dissolving 4 parts of an anionic emulsifier (sodium dodecylbenzenesulfonate) in 100 parts of water is added to a solution obtained by dissolving 100 parts of the modified petroleum resin A in 60 parts of toluene, and 1 at 1500 rpm using a homogenizer at 80 ° C. Emulsified for hours. Furthermore, the obtained emulsion was emulsified at 90 ° C. for 10 minutes using a gorin homogenizer to obtain an emulsion having a uniform particle size.
Thereafter, the toluene in the emulsion is removed by distillation under reduced pressure, followed by filtration through a 150 mesh stainless wire mesh, followed by filtration through a 500 mesh stainless wire mesh, from the modified petroleum resin A having a solid content concentration of 50%. A resin emulsion A1 was obtained. The volume average particle diameter of the resin emulsion A1 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.

15 parts of resin emulsion A was mixed with 100 parts of a solid content of an acrylic polymer emulsion (Water Base Adhesive: manufactured by ACHEM TECHNOLOGY CORPORATION) mainly composed of butyl acrylate units. An acrylic pressure-sensitive adhesive composition was prepared.
The obtained acrylic pressure-sensitive adhesive composition was applied onto a 25 μm thick polyester film using an applicator so that the thickness after drying was 25 μm, and dried to obtain a pressure-sensitive adhesive tape.
The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

(Example 2)
Resin emulsion B1 was obtained in the same manner as in Example 1 except that modified petroleum resin B was used instead of modified petroleum resin A. The volume average particle diameter of the resin emulsion B1 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion B1 was used instead of the resin emulsion A1. The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

(Example 3)
Except having changed the usage-amount of resin emulsion B1 as shown in Table 2, it carried out similarly to Example 2, and obtained the adhesive tape. The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

(Example 4)
The resin emulsion A1 was again filtered through a 500 mesh stainless steel wire mesh to obtain a resin emulsion A2 containing no modified petroleum resin particles of 30 μm or more. The volume average particle diameter of the resin emulsion A2 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion A2 was used instead of the resin emulsion A1. The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

(Comparative Example 1)
Resin emulsion C1 was obtained in the same manner as in Example 1 except that petroleum resin C was used instead of modified petroleum resin A. The volume average particle diameter of the resin emulsion C1 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion C1 was used instead of the resin emulsion A1. The peel adhesive strength, holding strength and initial adhesive strength of these adhesive tapes against polyethylene were measured. The results are shown in Table 2.

(Comparative Example 2)
Resin emulsion D1 was obtained in the same manner as in Example 1 except that modified petroleum resin D was used instead of modified petroleum resin A. The volume average particle diameter of the resin emulsion D1 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion D1 was used instead of the resin emulsion A1. The peel adhesive strength, holding strength and initial adhesive strength of these adhesive tapes against polyethylene were measured. The results are shown in Table 2.

(Comparative Example 3)
Resin emulsion E1 was obtained in the same manner as in Example 1 except that an aromatic hydrocarbon resin (“High Resin # 90” manufactured by Toho Chemical Co., Ltd.) was used in place of the modified petroleum resin A. The volume average particle diameter of the resin emulsion E1 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion E1 was used instead of the resin emulsion A1. The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

(Comparative Example 4)
Resin emulsion F1 was obtained in the same manner as in Example 1 except that rosin-based hydrocarbon resin ("Superester-A100", manufactured by Arakawa Chemical Co., Ltd.) was used instead of modified petroleum resin A. The volume average particle diameter of the resin emulsion F1 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion F1 was used instead of the resin emulsion A1. The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

(Comparative Example 5)
Resin emulsion C2 was obtained in the same manner as Comparative Example 1 except that the step of filtering through a wire mesh was not performed when the resin emulsion C1 was produced. The volume average particle diameter of the resin emulsion C2 and the ratio of the number of modified petroleum resin particles of 30 μm or more were measured, and the results are shown in Table 2.
An adhesive tape was obtained in the same manner as in Example 1 except that the resin emulsion C2 was used instead of the resin emulsion A1. The peel adhesive force, holding force and initial adhesive force of this adhesive tape to polyethylene were measured. The results are shown in Table 2.

Table 2 shows the following.
The acrylic pressure-sensitive adhesive composition of Comparative Example 1 to which the resin emulsion C1 having an acid value of less than 0.1% is added is slightly inferior in holding power and initial adhesive force, and inferior in peel adhesive strength to polyethylene.
The acrylic pressure-sensitive adhesive composition of Comparative Example 2 to which the resin emulsion D1 having a softening point of 30 ° C. or less is added has extremely low holding power and is inferior in peel adhesion to polyethylene.
The acrylic pressure-sensitive adhesive composition of Comparative Example 3 to which a resin emulsion E1 made of a commercially available aromatic hydrocarbon resin is added has a relatively good holding power, but has a poor peel adhesive strength to polyethylene and a sufficient initial adhesive strength. is not.
The acrylic pressure-sensitive adhesive composition of Comparative Example 4 to which the resin emulsion F1 made of a commercially available rosin-based hydrocarbon resin is added has a relatively good initial adhesive strength but is inferior in the peel adhesive strength and retention strength to polyethylene.
When the acrylic pressure-sensitive adhesive composition of Comparative Example 5 to which the resin emulsion C2 having an acid value of less than 0.1% and a high ratio of the number of modified petroleum resin particles of 30 μm or more is added is applied onto a substrate, the pressure-sensitive adhesive composition The surface of the object is rough, fish eyes are generated, a uniform film cannot be obtained, and the peel adhesion and initial adhesion are poor.

  In contrast to these comparative examples, the acrylic pressure-sensitive adhesive composition of Examples 1, 2 or 4 to which the resin emulsion A1, B1 or A2 of the present invention was added is excellent in peel adhesion to polyethylene, holding power and initial adhesion. Excellent balance of power. Moreover, even if the addition amount of the resin emulsion B1 is decreased, an acrylic pressure-sensitive adhesive composition having excellent peel adhesion to polyethylene and excellent balance of holding power and initial adhesive force is obtained (Examples 1 to 3). ).

The acrylic pressure-sensitive adhesive composition and the adhesive tape of the present invention include, for example, sanitary articles such as disposable paper diapers and sanitary napkins; food packaging such as frozen foods, fresh food and confectionery; member packaging such as automobile parts and machine parts; Packaging for electrical products such as audio products and refrigerators; bookbinding for slips, books, catalogs, etc .; bag making for craft bags, polypropylene bags, polyethylene bags, etc .; Applicable to clothing applications such as bonding of interlining.

Claims (7)

  It consists of 10 to 100% by mass of olefinically unsaturated hydrocarbon monomer units having 4 to 6 carbon atoms and 0 to 90% by mass of olefinically unsaturated hydrocarbon monomer units having 7 to 11 carbon atoms, and has a softening point of 30 ° C. A modified petroleum resin emulsion comprising the modified petroleum resin having an acid value of 0.1 to 100 KOHmg / g as described above.   The modified petroleum resin is composed of 40 to 95% by mass of an olefinically unsaturated hydrocarbon monomer unit having 4 to 6 carbon atoms and 5 to 60% by mass of an olefinically unsaturated hydrocarbon monomer unit having 7 to 11 carbon atoms. The modified petroleum resin emulsion according to claim 1, wherein   The modified petroleum resin emulsion according to claim 1 or 2, wherein the volume average particle diameter of the modified petroleum resin particles is 0.1 to 1 µm.   The modification | denaturation as described in any one of Claims 1-3 whose ratio of the number of the modification | denaturation petroleum resin particle | grains in the range of 30-64 micrometers in the modification | denaturation petroleum resin particle | grains in the particle diameter range of 4-64 micrometers is 1% or less. Petroleum resin emulsion.   An acrylic pressure-sensitive adhesive composition comprising an acrylic polymer emulsion and the modified petroleum resin emulsion according to any one of claims 1 to 4.   The acrylic pressure-sensitive adhesive composition according to claim 5, comprising 0.1 to 50 parts by mass of the modified petroleum resin emulsion based on 100 parts by mass of the solid content of the acrylic polymer emulsion.   A pressure-sensitive adhesive tape obtained by applying the acrylic pressure-sensitive adhesive composition according to claim 5 or 6 on a substrate.