JP2012140500A - Tackifier resin emulsion, method for producing the same and water-based tacky adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tackifier resin emulsion having a softening point of 80-160°C and producible in high stability and yield without using a solvent, a plasticizer, etc., in emulsifying process.SOLUTION: The tackifier resin emulsion having an organic solvent content of ≤50 ppm in the emulsion and having a volume-average particle diameter of ≤0.7 μm is produced by dispersing a petroleum resin having a softening point of 80-160°C in water in the absence of solvents and presence of an emulsifier component under pressure of 1-2.8 MPa.

Description

The present invention relates to a tackifying resin emulsion, a method for producing the same, and a water-based adhesive / adhesive composition.

In recent years, water-based adhesives and adhesives have been widely used because of their ability to reduce environmental impact, but as water-based applications have expanded, the required performance has become more sophisticated. Constant load peelability has come to be emphasized. One way to solve these problems is to use a tackifying resin emulsion having a high softening point. However, there are various problems in emulsifying a resin having a high softening point.

Conventionally, a high pressure emulsification method and a phase inversion emulsification method have been used as methods for producing a tackifying resin emulsion. In the former, a tackifier resin is dissolved in an organic solvent such as toluene to form a solution, and an appropriate emulsifier and water are added thereto, followed by forced emulsification using a high-shearing emulsifier (for example, a high-pressure emulsifier). In the latter method, an appropriate emulsifier is added to the heat-melted tackifying resin, and then water is added to form a water-in-oil emulsion. This is a method of obtaining an oil-in-water emulsion by combining.

In the high-pressure emulsification method, a stable emulsion can be obtained without any operational problems regardless of the softening point of the resin. However, since an organic solvent is used, there is a problem that it is not preferable for occupational safety and health when producing a tackifier resin emulsion. there were. In addition, since a step of removing the solvent by distillation under reduced pressure is indispensable, a lot of energy is consumed, and it is difficult to completely remove the solvent, and there is a problem that the solvent remains. Furthermore, as an organic solvent to be used, an aromatic organic solvent such as toluene is generally used from the viewpoint of workability and cost, but in recent years, the use of an aromatic organic solvent has been avoided due to its environmental impact. It has become to.

On the other hand, in the phase inversion emulsification method, since no solvent is used during the production of the tackifying resin emulsion, there is an advantage that no solvent is contained in the tackifying resin emulsion. Although the technology to obtain a stable emulsion has been established, the high softening point resin has poor dispersibility, so that a large amount of coagulum is produced as a by-product, resulting in a significant decrease in yield and workability during filtration. Was holding.

As an improvement method, in Patent Document 1, an acrylic oligomer having a weight average molecular weight of 500 to 50,000 is used as a plasticizer component, and a rosin resin having a softening point of 120 to 190 ° C. is used as a tackifier resin under a pressure condition of 1 MPa or less. However, since the softening point of the tackifying resin is substantially lowered, there is a problem that the holding power and the constant load peelability of the obtained adhesive are significantly reduced.

JP 2005-330436 A

The present invention provides a stable and high yield of a tackifying resin emulsion having a softening point of 80 to 160 ° C. that can impart good holding power and constant load peelability without using a solvent or plasticizer in the emulsification step. The purpose is to provide.

As a result of intensive studies to solve the above problems, the present inventors pay attention to the type of tackifying resin and the pressure in the emulsifying apparatus, and emulsify under a specific range of pressure using a specific petroleum resin. Thus, the inventors have found that the above-mentioned problems can be solved and completed the present invention.

That is, the present invention
A tackifying resin emulsion obtained by dispersing a petroleum resin having a softening point of 80 to 160 ° C. in water in the absence of a solvent and in the presence of an emulsifier component under a pressure of 1 to 2.8 MPa; The tackifying resin emulsion having a volume average particle size of 0.7 μm or less at 50 ppm or less; the tackifying resin emulsion in which 10% by weight or more of the total emulsifier component is a high molecular weight emulsifier; 80% by weight or more of the total emulsifier component The tackifying resin emulsion is a high molecular weight emulsifier; the high molecular weight emulsifier is an acrylamide polymer obtained by using 50 mol% or more of a (meth) acrylamide monomer; A water-based adhesive / adhesive composition comprising a petroleum resin having a softening point of 80 to 160 ° C. In standing under a method for producing tackifier resin emulsion, wherein the dispersing in water under a pressure of 1～2.8MPa, relates.

The tackifying resin emulsion of the present invention has good storage stability, and the adhesive / adhesive composition obtained using the tackifying resin emulsion has a particularly high holding force and constant load peeling compared to conventional ones. Good properties. Moreover, since the tackifying resin emulsion of the present invention does not contain an organic solvent, it is preferable in terms of safety and hygiene for manufacturers of tackifying resin emulsions and sticky / adhesives, and those who use sticky / adhesives. In particular, it can be suitably used for building materials, automotive adhesives and adhesives that require high holding power and constant load peelability and have strict standards for residual solvents in products.

The method for producing a tackifying resin emulsion of the present invention is obtained by dispersing a petroleum resin having a softening point of 80 to 160 ° C. in water in the presence of a solvent-free and emulsifier component under a pressure of 1 to 2.8 MPa.

The petroleum resin used in the present invention is not particularly limited as long as it has a softening point of 80 to 160 ° C., and a known resin can be used. Examples of petroleum resins include C5 petroleum resins obtained from C5 fractions of naphtha such as pentene, pentadiene, and isoprene; naphtha such as indene, methylindene, vinyltoluene, styrene, α-methylstyrene, and β-methylstyrene. C9 petroleum resin obtained from C9 fraction; C5-C9 copolymer petroleum resin obtained from C5 fraction and C9 fraction; Pure monomer resin obtained by polymerizing styrene or the like as main component; DCPD petroleum resins obtained from hydrides of these petroleum resins.

The tackifying resin emulsion of the present invention is obtained by emulsifying the petroleum resin.
When emulsifying petroleum resin, an emulsifier is usually used. It does not specifically limit as an emulsifier to use, A well-known emulsifier can be used. Specific examples include a high molecular weight emulsifier obtained by polymerizing a vinyl monomer, a low molecular weight anionic emulsifier, and a low molecular weight nonionic emulsifier. These may be used individually by 1 type, or may use several types together. In the present invention, it is particularly preferable to use a high molecular weight emulsifier because adhesion performance (particularly holding power) and mechanical stability can be improved.

Examples of the monomer used for the production of the high molecular weight emulsifier include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and (meth) acrylate n. -Butyl, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, polyoxyalkylene (meth) acrylate, (Meth) acrylic acid ester monomers such as (meth) acrylic acid, crotonic acid and other monocarboxylic acid vinyl monomers; maleic acid, maleic anhydride, fumaric acid, itaconic acid, muconic acid and other dicarboxylic acids Vinyl monomers; vinyl sulfonic acid, styrene sulfonic acid, 2-a Organic sulfonic acid vinyl monomers such as rilamido-2-methylpropane sulfonic acid; phosphoric acid such as 2- (meth) acryloyloxyethyl acid phosphate and phosphate ester vinyl monomers such as diphenyl-2 (meth) acryloyloxyphosphate Vinyl monomers; and alkali metal salts such as sodium salts and potassium salts of these various organic acids, alkaline earth metal salts, ammonium salts, salts of organic bases; (meth) acrylamide, N-methylol (meth) acrylamide, etc. (Meth) acrylamide monomers; nitrile monomers such as (meth) acrylonitrile; vinyl ester monomers such as vinyl acetate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (Meth) acrylic acid -Hydroxy group-containing (meth) acrylic acid ester monomers such as hydroxybutyl; methyl vinyl ether, glycidyl (meth) acrylate, urethane acrylate, C6-C22 α-olefin, vinyl pyrrolidone and other monomers And those obtained by polymerizing one or more of these by a known method.

Examples of the copolymerization method of these monomer components include solution polymerization, suspension polymerization, emulsion polymerization using a reactive emulsifier other than the high molecular weight emulsifier described later, and a non-reactive emulsifier other than the high molecular weight emulsifier.

The weight average molecular weight of the high molecular weight emulsifier thus obtained (polystyrene conversion value by gel permeation chromatography method) is not particularly limited, but it is usually about 1000 to 500,000, and the tackifying resin obtained with emulsifying ability. Preferred in the performance of the emulsion. In addition, it is preferable to use a (meth) acrylamide polymer obtained by using 50 mol% or more of a (meth) acrylamide monomer in terms of the coating performance and holding power of the pressure-sensitive adhesive and the initial adhesiveness of the adhesive.

Examples of reactive emulsifiers other than high molecular weight emulsifiers include surfactants having a hydrophilic group such as a sulfonic acid group and a carboxyl group, and a hydrophobic group such as an alkyl group and a phenyl group. It has a double bond. Examples of the carbon-carbon double bond include functional groups such as a (meth) allyl group, 1-propenyl group, 2-methyl-1-propenyl group, vinyl group, isopropenyl group, and (meth) acryloyl group. . Specific examples of the reactive emulsifier include, for example, polyoxyethylene alkyl ether having at least one functional group in the molecule, polyoxyethylene phenyl ether having at least one functional group in the molecule, and sulfosuccinic acid thereof. And polyoxyethylene alkylphenyl ethers having at least one functional group in the molecule, sulfosuccinic acid ester salts, sulfuric acid ester salts, phosphoric acid ester salts, fats thereof. Amino acid or aromatic carboxylate, acidic phosphoric acid (meth) acrylate ester emulsifier, acid anhydride modified product of rosin glycidyl ester acrylate (see JP-A-4-256429), JP-A-63- No. 23725, JP-A 63-240 31 JP include those various emulsifiers such as described in JP-A-62-104802.

Furthermore, what replaced polyoxyethylene in the said reactive emulsifier with polyoxypropylene or the block copolymerization or random copolymerization of polyoxyethylene and polyoxypropylene is mentioned. In addition, as these commercial items, for example, “KAYAMER PM-1”, “KAYAMER PM-2”, “KAYAMER PM-21” (manufactured by Nippon Kayaku Co., Ltd.), “SE-10N”, “ "NE-10", "NE-20", "NE-30", "Adekalia Soap SR-10", "Adekalia Soap SR-20", "Adekalia Soap ER-20" (above, ADEKA Corporation) Manufactured), "New Frontier A229E", "New Frontier N117E", "New Frontier N250Z", "Aquaron RN-10", "Aquaron RN-20", "Aquaron RN-50", "Aquaron HS-10", " "Aqualon KH-05", "Aquaron KH-10" (Daiichi Kogyo Seiyaku Co., Ltd.), "Eleminol JS-2" (Sanyo Kasei) Made business Co., Ltd.), "LATEMUL K-180" (manufactured by Kao Corp.), and the like can be cited as a typical example.

As reactive emulsifiers other than these high molecular weight emulsifiers, polyoxyethylene alkyl ethers are preferred from the viewpoint of polymerizability and the emulsifying properties of the resulting high molecular emulsifier, and have at least one (meth) allyl group in the molecule. It is particularly preferable to use a sulfate ester salt of polyoxyethylene alkyl ether. As these commercial products, “ADEKA rear soap SR-10”, “ADEKA rear soap SR-20” (trade name, manufactured by ADEKA Corporation), “AQUARON KH-05”, “AQUARON KH-10” (No. 1) Ichi Kogyo Seiyaku Co., Ltd.) is preferable.

Non-reactive emulsifiers other than high molecular weight emulsifiers include, for example, dialkyl sulfosuccinic acid ester salts, alkane sulfonic acid salts, α-olefin sulfonic acid salts, polyoxyethylene alkyl ether sulfosuccinic acid ester salts, polyoxyethylene styryl phenyl ether sulfosuccinic acid esters. Anionic emulsifiers such as salt, naphthalenesulfonic acid formalin condensate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkylphenyl ether sulfate, polyoxyethylene alkyl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene sorbitan Nonionic emulsifiers such as fatty acid esters are exemplified.

These emulsifiers other than the high molecular weight emulsifier can be used alone or in combination of two or more. Among these, anionic emulsifiers and nonionic emulsifiers are preferably used from the viewpoints of compatibility with the base polymer used in the adhesive / adhesive composition and mixing stability.

In addition, the usage-amount of an emulsifier is about 1-10 weight part normally in conversion of solid content with respect to 100 weight part of petroleum-type resin, Preferably it is 2-8 weight part. When the amount of the emulsifier used is 1 part by weight or more, reliable emulsification can be performed, and when it is 10 parts by weight or less, high water resistance and adhesive performance can be ensured. Further, it is preferable to use at least 10% by weight or more, preferably 80% by weight or more of the total emulsifier component as a high molecular weight emulsifier because the holding power can be further improved.

In the method for producing the tackifying resin emulsion of the present invention, a petroleum resin is melted and stirred without using a solvent, an emulsifier and water are added in predetermined amounts under a pressure of 1 to 2.8 MPa, and the petroleum resin is continuously added. Forming an emulsion in which water is a dispersed phase and then adding water to invert the emulsion to form an emulsion in which petroleum resin is a dispersed phase and water is a continuous phase It is.

In the method for producing a tackifying resin emulsion of the present invention, by setting the pressurizing condition (for example, the pressure in the emulsifying apparatus) during the emulsification dispersion within the range of 1 to 2.8 MPa, the dispersibility is good. As a result, it is possible to obtain an emulsion that suppresses the generation of coagulum, has high yield, and has excellent storage stability. When the pressurizing condition is less than 1 MPa, dispersibility is deteriorated. As a result, a large amount of coagulum is generated, and the yield is greatly reduced. Also, when the pressurization condition exceeds 2.8 MPa, the dispersibility is lowered, and a large amount of coarse particles are observed, and the yield and the storage stability of the emulsion are lowered. In addition, production that may exceed the tolerance of pressure resistance such as sealing materials used in dispersible emulsifying devices, is prone to equipment failures, and cannot withstand continuous operation for a long time. There is a problem with sex.

In addition, in the manufacturing method of the tackifying resin emulsion of this invention, stirring conditions and the addition conditions of an emulsifier and water can each be determined suitably.

As an emulsifying apparatus used in the production of the tackifying resin emulsion of the present invention, an auto autoclave provided with a stirring blade can be used, and in addition, a high shear type rotary emulsifier or the like can be used.

As autoclaves equipped with stirring blades, various sizes and types of stirring are commercially available. For example, Nack drive type stirrer (manufactured by Nack Autoclave Co., Ltd.), magnetic induction stirring type autoclave LC series, FC series (manufactured by Toyo High Pressure Co., Ltd.), electromagnetic induction rotary stirring type autoclave MK type (Kurihara Seisakusho Co., Ltd.) A reactor (HES Co., Ltd.), a pressurized batch reactor (Cosmo Engineering Co., Ltd.) and the like can be exemplified.

As a high shear rotary type emulsifier, T.W. K. Homomixer, T.W. K. Philmix (manufactured by Primix Co., Ltd.), Homomixer (manufactured by Mizuho Kogyo Co., Ltd., etc.), Claremix (manufactured by M Technique Co., Ltd.), Sherpump (manufactured by Fristan Pump Japan Co., Ltd.), Onrator , Rotary mixer (manufactured by Sakai Seisakusho Co., Ltd.), milder (manufactured by Sakakibara Seisakusho Co., Ltd.), pentax mixer (manufactured by Branloube), Cavitron (manufactured by Eurotech Co., Ltd.) and the like.

The solid content concentration of the tackifying resin emulsion thus obtained is not particularly limited, but is usually adjusted appropriately so as to be about 20 to 70% by weight. Moreover, the volume average particle diameter of the obtained emulsion is usually about 0.1 to 2 μm, and most of them are uniformly dispersed as particles of 1 μm or less, but the volume average particle diameter is 0.7 μm or less. It is preferable from the viewpoint of storage stability. The emulsion has a white to milky white appearance, has a pH of about 2 to 10, a viscosity of usually about 10 to 1000 mPa · s (at 25 ° C. and a solid content concentration of 50%), and an organic solvent in the emulsifying and dispersing step. Therefore, the organic solvent content is 50 ppm or less.

The water-based adhesive / adhesive composition of the present invention is obtained by blending the tackifier resin emulsion with at least one base polymer selected from the group consisting of an acrylic polymer emulsion, a rubber latex and a synthetic resin emulsion. The solid content concentration of these aqueous adhesive / adhesive compositions is usually about 40 to 70% by weight, preferably 55 to 70% by weight.

As the acrylic polymer emulsion, those generally used for various acrylic adhesives and adhesives can be used, such as batch preparation polymerization of monomers such as (meth) acrylic acid ester, monomer sequential addition polymerization method, emulsion monomer It can be easily produced by a known emulsion polymerization method such as a sequential addition polymerization method or a seed polymerization method.

Examples of the (meth) acrylic acid ester to be used include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and glycidyl (meth) acrylate. , (Meth) acrylic acid 2-hydroxyethyl and the like, and these may be used alone or in admixture of two or more. Further, in order to impart storage stability to the resulting emulsion, a small amount of (meth) acrylic acid may be used instead of the (meth) acrylic acid ester. Furthermore, if desired, a copolymerizable monomer such as vinyl acetate or styrene can be used in combination as long as the adhesive properties of the (meth) acrylic acid ester polymer are not impaired. The emulsifier used in the acrylic polymer emulsion may be an anionic emulsifier, partially saponified polyvinyl alcohol, etc., and the amount used is about 0.1 to 5 parts by weight, preferably 100 parts by weight of the polymer. 0.5 to 3 parts by weight.

The use ratio of the acrylic polymer emulsion and the tackifier resin emulsion is not particularly limited, but the effect of the modification by the tackifier resin emulsion can be sufficiently expressed, and the retention force and the constant load peelability are reduced by excessive use. As an appropriate range of use that does not cause the tackifier resin emulsion, the tackifying resin emulsion is usually about 2 to 40 parts by weight (in terms of solid content) with respect to 100 parts by weight (in terms of solid content) of the acrylic polymer emulsion.

Moreover, as rubber latex, various well-known things used for an aqueous | water-based adhesive / adhesive composition can be used. Examples thereof include natural rubber latex, styrene-butadiene copolymer latex, chloroprene latex and the like.

The ratio of rubber latex and tackifying resin emulsion used is not particularly limited, but the effect of modification by tackifying resin emulsion can be fully expressed, and it does not cause a decrease in retention and olefin adhesion due to excessive use. As such a use range, the tackifying resin emulsion is usually about 10 to 150 parts by weight (in terms of solid content) with respect to 100 parts by weight of rubber latex (in terms of solid content).

As the synthetic resin emulsion, various known ones used in aqueous adhesive compositions can be used, and examples thereof include synthetic resin emulsions such as vinyl acetate emulsion, ethylene-vinyl acetate copolymer emulsion, and urethane emulsion.

The use ratio of the synthetic resin emulsion and the tackifier resin emulsion is not particularly limited, but the effect of modifying the tackifier resin emulsion can be sufficiently exhibited, and the retention force and the constant load peelability are reduced due to excessive use. As an appropriate use ratio, the tackifying resin emulsion is usually about 2 to 40 parts by weight (in terms of solid content) with respect to 100 parts by weight (in terms of solid content) of the synthetic resin emulsion.

In the water-based adhesive / adhesive composition of the present invention, an acrylic polymer emulsion, a rubber latex and a synthetic resin emulsion can be used in combination as a base polymer, and if necessary, an antifoaming agent, a thickener, Fillers, antioxidants, water resistance agents, film-forming aids and the like can also be used.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. In each example, all parts and percentages are by weight unless otherwise specified. The obtained polymer emulsifier and adhesive resin emulsion were analyzed by the following method.

(Yield of tackifying resin emulsion)
The yield of the obtained tackifying resin emulsion was determined by the following formula.

[formula]
Yield = weight of obtained emulsion × non-volatile content / weight of charged solid content × 100

(Solvent content in tackifying resin emulsion)
The solvent in the emulsion was measured by gas chromatography (manufactured by Shimadzu Corporation, trade name “GC-14A”, column: J & W, trade name “DB-5”), and a calibration curve using an aqueous solution of known solvent concentration. The content was determined. The detection limit (nd) of the organic solvent by this measurement is 10 ppm.

(Volume average particle diameter of tackifying resin emulsion)
Using a laser diffraction particle size analyzer (manufactured by Shimadzu Corporation, trade name “SALD-2000”), the measurement was performed under the conditions of a refractive index of 1.70-0.20i and an absorbance of 0.06.

(Evaluation of storage stability of tackifier resin emulsion)
The obtained tackifying resin emulsion was allowed to stand at 25 ° C. for 10 days, and the presence or absence of sediment was visually determined. The results are shown in Table 1.
○: Good △: Small amount of sediment ×: Large amount of sediment

Production Example 1 [Production of Styrenic Polymer Emulsifier]
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, a polyoxyethylene phenyl ether-based reactive emulsifier (trade name “Aqualon RN-50”: Daiichi Kogyo Seiyaku Co., Ltd.) in a nitrogen gas stream. (Made by Co., Ltd.) is charged with 25 parts in terms of solid content, 12.5 parts of styrene, 12.5 parts of methyl methacrylate, 40 parts of methacrylic acid and 10 parts of sodium styrene sulfonate, and further 20 parts of water is added. The ingredients were transparent and homogeneous. Next, 1 part of dodecanethiol, 2 parts of benzoyl peroxide and 300 parts of water were mixed with this to initiate polymerization. After stirring at 65 ° C. for 2 hours, 29 parts of 28% aqueous ammonia was added, and the mixture was further stirred at 65 ° C. for 6 hours to complete the polymerization, and then cooled to room temperature. An aqueous solution of a copolymer having a nonvolatile content of 22.5% and a weight average molecular weight of 50,000 was obtained.

Production Example 2 [Production of acrylamide polymer emulsifier]
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, 25.1 parts of acrylamide (39.1 mol% of the total molar amount of monomers, the same applies hereinafter), 50 parts of itaconic acid ( 42.5 mol%), 2-acrylamido-2-methylpropanesulfonic acid 9.2 parts (4.9 mol%), butyl acrylate 15.7 parts (13.5 mol%), lauryl mercaptan 5 parts, poly Sodium oxyethylene alkyl ether sulfate ester salt (anionic emulsifier: trade name “Hytenol 073”: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 5 parts of ammonium persulfate and 400 parts of water were mixed and heated at 80 ° C. Reaction was performed for 5 hours to obtain an aqueous solution of the copolymer. Thereafter, the mixture was cooled, 2-acrylamido-2-methylpropanesulfonic acid and equimolar sodium hydroxide were added at 60 ° C., and the mixture was stirred for 1 hour to obtain an aqueous solution of a copolymer having a concentration of 15% and a weight average molecular weight of 35,000. .

Production Example 3 [Production of acrylamide polymer emulsifier]
In a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, 57.7 parts of acrylamide (73 mol% of the total molar amount of monomers, the same applies hereinafter), 21.7 parts of itaconic acid ( 15 mol%), 2-acrylamido-2-methylpropanesulfonic acid 9.2 parts (4 mol%), butyl acrylate 11.4 parts (8 mol%), lauryl mercaptan 5 parts, polyoxyethylene alkyl ether sulfate Sodium salt (anionic emulsifier: trade name “Hytenol 073”: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 5 parts of ammonium persulfate and 400 parts of water were mixed and heated, and reacted at 80 ° C. for 5 hours. An aqueous solution of the polymer was obtained. Thereafter, the mixture was cooled, and 2-acrylamido-2-methylpropanesulfonic acid and equimolar sodium hydroxide were added at 60 ° C. and stirred for 1 hour to obtain an aqueous solution of a copolymer having a concentration of 15% and a weight average molecular weight of 40000. .

Production Example 4 [Production of base polymer emulsion]
In a reaction vessel equipped with a stirrer, thermometer, reflux condenser, dropping funnel and nitrogen inlet tube, 43.4 parts of water and polyoxyethylene alkyl ether sulfate sodium salt (anionic emulsifier: trade name) under a nitrogen gas stream An aqueous solution consisting of 0.92 part of “Hitenol 073” (Daiichi Kogyo Seiyaku Co., Ltd.) was charged and the temperature was raised to 70 ° C. Next, a mixture comprising 90 parts of butyl acrylate, 7 parts of 2-ethylhexyl acrylate and 3 parts of acrylic acid, 0.24 parts of potassium persulfate (polymerization initiator), 0.11 part of pH adjusting agent (bicarbonate) and water 1/10 amount of each 8.83 parts of the initiator aqueous solution was added to the reaction vessel, and prepolymerization was performed at 70 ° C. for 30 minutes under a nitrogen gas stream. Next, the remaining 9/10 amount of the mixture and the aqueous initiator solution was added to the reaction vessel over 2 hours to carry out emulsion polymerization, and then held at 70 ° C. for 1 hour to complete the polymerization reaction. The acrylic polymer emulsion thus obtained was cooled to room temperature and then filtered using a 100 mesh wire net to obtain an acrylic polymer emulsion having a solid content of 47.8%.

Example 1 [Production of Tackifying Resin Emulsion]
A pressure batch reactor equipped with a stirrer, a condenser, a thermometer, and a dropping funnel (manufactured by Cosmo Engineering Co., Ltd.) is used. 140 ", manufactured by JX Nippon Oil & Energy Corporation, and melted at 170 ° C for about 1 hour. Thereafter, the reactor was pressurized to 1 MPa with nitrogen, and 5 parts (in terms of solid content) of an anionic emulsifier (trade name “Neohaitenol F-13”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) were stirred under pressure. Then, 15 parts of hot water was added using a dropping funnel while keeping the inside of the system at 170 ° C. to obtain a creamy water-in-oil emulsion. Next, 54 parts of hot water at 170 ° C. was added with vigorous stirring to invert the phase to obtain an oil-in-water emulsion, and further diluted with hot water to a concentration of 50%. The emulsion was cooled to 25 ° C. and filtered through a 250 mesh wire mesh to obtain a tackifying resin emulsion.

Examples 2-8
A tackifying resin emulsion was obtained in the same manner as in Example 1 except that the tackifying resin and emulsifier used, and the pressure conditions of the emulsifying apparatus were changed as shown in Table 1.

Example 9
A tackifier resin emulsion was obtained in the same manner as in Example 1 except that a homomixer was installed in the pressure batch reactor used, and the emulsifier and hot water were added and operated at a rotation speed of 500 rpm.

Comparative Example 1
100 parts of a C9 petroleum resin having a softening point of 145 ° C. (trade name “Nisseki Neopolymer 140”, manufactured by JX Nippon Mining & Energy Corporation), which is a tackifier resin, is used in the same pressure batch reactor as in Example 1. Was melted at 160 ° C. for about 1 hour. Thereafter, the reactor was pressurized to 0.4 MPa with nitrogen, and 5 parts of an anionic emulsifier (trade name “Neohaitenol F-13”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was stirred under pressure. As a result, the system temperature decreased to 140 ° C. A creamy water-in-oil emulsion was obtained by adding 15 parts of hot water from the dropping funnel while maintaining 0.2 MPa. Next, 54 parts of 120 ° C. hot water was added with vigorous stirring to invert the phase to obtain an oil-in-water emulsion, and further diluted with hot water to a concentration of 50%. Next, when the emulsion was cooled, noise was generated during the cooling, and stirring was stopped. The emulsion was extracted from the bottom discharge valve and filtered through a 250 mesh wire net. The volume average particle size of the obtained emulsion was 2.00 μm. A large amount of coagulum was generated in the emulsifier, and the yield was 15%.

Comparative Example 2
100 parts of a C9 petroleum resin having a softening point of 145 ° C. (trade name “Nisseki Neopolymer 140”, manufactured by JX Nippon Mining & Energy Corporation), which is a tackifier resin, is used in the same pressure batch reactor as in Example 1. Was melted at 180 ° C. for about 1 hour. Thereafter, the reactor was pressurized to 3.0 MPa with nitrogen, and 5 parts of an anionic emulsifier (trade name “Neohaitenol F-13”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) were stirred under pressure. Then, 15 parts of hot water was added from the dropping funnel while maintaining the inside of the system at 180 ° C. to obtain a creamy water-in-oil emulsion. Next, 54 parts of 180 ° C. hot water was added with vigorous stirring to invert the phase to obtain an oil-in-water emulsion, and leakage occurred from the stirring shaft and the bottom drain valve during the addition of hot water. After being diluted with hot water as it is to a concentration of 50%, the emulsion was cooled to 25 ° C. and filtered through a 250 mesh wire mesh to obtain a tackifying resin emulsion. The volume average particle diameter of the obtained emulsion was 0.73 μm. Also, a lot of coagulum was generated, and the yield was 70%.

Comparative Example 3
A tackifying resin emulsion was obtained in the same manner as in Example 1 except that the tackifying resin and emulsifier used, and the pressure conditions of the emulsifying apparatus were changed as shown in Table 1.

Comparative Example 4
80 parts of a C9 petroleum resin having a softening point of 145 ° C. (trade name “Nisseki Neopolymer 140”, manufactured by JX Nippon Mining & Energy Co., Ltd.), which is a tackifying resin, is used in the same pressure batch reactor as in Example 1. And 20 parts of a butyl acrylate polymer (trade name “ARUFON UP-1021” manufactured by Toagosei Co., Ltd.) having a glass transition temperature of −71 ° C. and a weight average molecular weight of 1600, and melted at 160 ° C. for about 1 hour. A tackifying resin mixture having a softening point of 90 ° C. was obtained. Then, it cools to 120 degreeC, pressurizes a reactor to 0.2 Mpa with nitrogen, 5 parts of an anionic emulsifier (brand name "Neohaitenol F-13", Daiichi Kogyo Seiyaku Co., Ltd. product) under pressure ( (In terms of solid content) was added with stirring, and 15 parts of hot water was added from the dropping funnel while maintaining the inside of the system at 120 ° C. to obtain a creamy water-in-oil emulsion. Next, 54 parts of 120 ° C. hot water was added with vigorous stirring to invert the phase to obtain an oil-in-water emulsion, and further diluted with hot water to a concentration of 50%. The emulsion was cooled to 25 ° C. and filtered through a 250 mesh wire mesh to obtain a tackifying resin emulsion.

Comparative Example 5
100 parts of a C9 petroleum resin (trade name “Nisseki Neopolymer 140”, manufactured by JX Nippon Oil & Energy Corporation) with a softening point of 145 ° C., which is a tackifying resin, is dissolved in 60 parts of toluene at 100 ° C. for about 1 hour. After cooling to 80 ° C., 3 parts of an anionic emulsifier (trade name “Neohaitenol F-13”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 160 parts of water are added and 75 parts are added. Pre-emulsification was performed by vigorous stirring for 1 hour at ° C. The obtained preliminary emulsion was high-pressure emulsified with a high-pressure emulsifier (mantongaurin) at a pressure of 30 MPa to obtain an emulsion. Next, the emulsion was charged into a vacuum distillation apparatus, and vacuum distillation was performed for 6 hours under conditions of 50 ° C. and 130 hPa, to obtain a tackifier resin emulsion having a solid content of 50%.

(Evaluation method of aqueous adhesive composition)
To the preparation obtained by mixing 100 parts of the acrylic polymer emulsion obtained in Production Example 4 (in terms of solid content) and 10 parts of the tackifier resin emulsion obtained in the above Examples and Comparative Examples (in terms of solid content), A pressure-sensitive adhesive composition was obtained by adding 0.5 part of a thickener (trade name “Primal ASE-60”, manufactured by Nippon Acrylic Chemical Co., Ltd.).

(Adhesion performance test)
The above water-based pressure-sensitive adhesive composition is dried on a polyester film (trade name “S-100”, manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.) with a thickness of 38 μm using a dice-type applicator (manufactured by Otsugi Equipment Co., Ltd.). The film was applied to a certain degree, and then dried for 5 minutes in a circulating dryer at 105 ° C. to prepare a film for a sample tape. The adhesive properties were evaluated by the following test methods. The evaluation results are shown in Table 2. In addition, the number of each evaluation example respond | corresponds to the number of the Example of an aqueous adhesive composition.

(1) Holding power A sample tape (width 25 mm × length 25 mm) was prepared from the sample tape film, attached to a stainless steel plate, a load of 1 kg was applied at 60 ° C., and the drop time (hours) was measured. .
(2) Constant load peelability A sample tape (25 mm in width x 150 mm in length) was prepared from the film for sample tape, and was laminated on a polypropylene plate and bonded by reciprocating twice with a roller having a weight of 2 kg. Immediately thereafter, a load of 200 g was applied to the end of the sample tape, the sample was fixed so as to be peeled at 90 °, and the peel distance (mm) per hour was measured at 23 ° C.

In the table, n. d. Indicates that it is below the detection limit (10 ppm).
Resin a: C9 petroleum resin having a softening point of 145 ° C. (trade name “Nisseki Neopolymer 140”, manufactured by JX Nippon Oil & Energy Corporation)
Resin b: C9 petroleum resin having a softening point of 160 ° C. (trade name “Nisseki Neopolymer 170S”, manufactured by JX Nippon Oil & Energy Corporation)
Resin c: C5-C9 petroleum resin having a softening point of 86 ° C. (trade name “Quinton U185”, manufactured by Nippon Zeon Co., Ltd.)
Resin d: C9 hydrogenated petroleum resin having a softening point of 100 ° C. (trade name “Arcon M-100”, manufactured by Arakawa Chemical Industries, Ltd.)
Resin e: C5-C9 petroleum resin having a softening point of 115 ° C. (trade name “Quinton G115”, manufactured by Nippon Zeon Co., Ltd.)
Resin f: C5 petroleum resin having a softening point of 70 ° C. (trade name “Quinton B170”, manufactured by Nippon Zeon Co., Ltd.)
Resin g: butyl acrylate polymer having a weight average molecular weight of 1600 (trade name “ARUFON UP-1021”, manufactured by Toagosei Co., Ltd.)
Emulsifier a: Anionic emulsifier (trade name “Neohaitenol F-13”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)

Claims (7)

A tackifying resin emulsion obtained by dispersing a petroleum resin having a softening point of 80 to 160 ° C in water in the presence of no solvent and an emulsifier component under a pressure of 1 to 2.8 MPa. The tackifier resin emulsion according to claim 1, wherein the content of the organic solvent is 50 ppm or less and the volume average particle diameter is 0.7 µm or less. The tackifier resin emulsion according to claim 1 or 2, wherein 10% by weight or more of the total emulsifier component is a high molecular weight emulsifier. The tackifier resin emulsion according to claim 3, wherein 80% by weight or more of the total emulsifier component is a high molecular weight emulsifier. The tackifier resin emulsion according to claim 3 or 4, wherein the high molecular weight emulsifier is an acrylamide polymer obtained by using 50 mol% or more of a (meth) acrylamide monomer. A water-based adhesive / adhesive composition comprising the tackifying resin emulsion according to any one of claims 1 to 5. A method for producing a tackifier resin emulsion, comprising dispersing a petroleum resin having a softening point of 80 to 160 ° C. in water in the presence of no solvent and an emulsifier component under a pressure of 1 to 2.8 MPa.