JP5387955B2 - Rosin emulsion - Google Patents

Description

The present invention relates to a rosin emulsion.

  A rosin emulsion is generally a rosin derivative such as rosin ester or rosin dispersed in water as fine particles in the presence of a low molecular emulsifier or a high molecular emulsifier made of an acrylic copolymer. Conventionally, it has been awarded as a tackifier for water-based adhesives / adhesives such as labels, sheets, tapes, packaging, and building materials, or as a sizing agent for papermaking.

  Specifically, for example, Patent Document 1 describes an emulsion-type tackifier obtained by emulsifying colorless rosins in the presence of a polymer emulsifier containing styrene as an essential component. It is said that a water-based adhesive / adhesive can be obtained by blending in a polymer emulsion. Patent Document 2 discloses an emulsion-type paper sizing agent in which rosins are dispersed in the presence of an acrylic copolymer comprising (meth) acrylic acid esters and an anionic unsaturated monomer. Have been described.

  By the way, in the rosin emulsion described in Patent Documents 1 and 2, the acrylic copolymer as the polymer emulsifier and the rosin are separated, in other words, both exist without a chemical bond. It is what. Therefore, it is considered that a rosin emulsion in which an acrylic copolymer formed by chemically bonding rosins (forming resin acid) is dispersed as fine particles has a function not found in conventional ones.

JP-A-7-331208 JP-A-2-33393

An object of the present invention is to provide a rosin emulsion in which an acrylic copolymer formed by chemically bonding a resin acid is dispersed as fine particles.

The present inventor has found that a desired rosin emulsion can be provided by using a specific (meth) acryloyl group-containing rosin derivative as a constituent component as the acrylic copolymer.

That is, in the present invention, a (meth) acryloyl group-containing monovinyl ether compound and one rosin selected from the group consisting of gum rosin, tall oil rosin, wood rosin, hydrogenated rosin and disproportionated rosin undergo a hemiacetal esterification reaction. A rosin derivative (a-1) (hereinafter referred to as component (a-1)) , one styrene selected from the group consisting of styrene, α-methylstyrene, t-butylstyrene and dimethylstyrene, and acryloylmorpholine. monofunctional vinyl compounds containing (a-2) (hereinafter, (a-2) component of) a rosin-based copolymer and is obtained by copolymerization reaction (A) (hereinafter, (A) referred to as component) and dispersed A rosin emulsion.

The rosin emulsion of the present invention is an acrylic copolymer obtained by chemically bonding a resin acid and dispersed in water as fine particles. Is done.

In addition, the rosin emulsion of the present invention can be used for the same uses (tackifier, paper sizing agent, etc.) as conventional rosin emulsions. In addition, the water-based adhesive / adhesive composition containing the tackifier containing the rosin emulsion of the present invention can be suitably used for a wide range of applications such as tapes, sheets, labels, packaging, and building materials.

  The component (a-1) is a rosin derivative formed by a hemiacetalization reaction of a (meth) acryloyl group-containing monovinyl ether compound and rosins, and for example, those described in JP-A-2008-106047 can be used. .

  Specific examples of the (meth) acryloyl group-containing monovinyl ether compound include, for example, an alkyleneoxy group-containing monovinyl ether compound [(meth) acrylic acid 2- (2-vinyloxyethoxy) ethyl, (meth) acrylic acid 2- (1-methyl-2-vinyloxyethoxy) ethyl, (meth) acrylic acid 3- (2-vinyloxyethoxy) propyl, etc.], alkyl group-containing monovinyl ether compounds [(meth) acrylic acid 2-vinyloxyethyl, (meth) 3-vinyloxypropyl acrylate, 1-methyl-2-vinyloxyethyl (meth) acrylate, etc.], cycloalkyl group-containing monovinyl ether compounds [4-vinyloxycyclohexyl (meth) acrylate, 4-vinyl methacrylate (meth) acrylate Roxymethylcyclohexylmethyl, (meth) acrylic acid 3 Vinyloxymethylcyclohexylmethyl etc.], phenyl group aromatic group-containing monovinyl ether compound [(meth) acrylic acid p-vinyloxymethylphenylmethyl, (meth) acrylic acid m-vinyloxymethylphenylmethyl, (meth) acrylic acid o -Vinyloxymethylphenylmethyl and the like], and the like can be used singly or in combination of two or more. Among these, an oxyalkylene group-containing monovinyl ether compound, particularly 2- (2-vinyloxyethoxy) ethyl (meth) acrylate is preferable because it is easily available.

The rosins, specifically, for example, a natural rosin gum rosin, tall oil rosin and wood rosin, and hydrogenated rosin and disproportionated a stabilized rosin obtained by treating the natural rosin by various known methods There may be mentioned at least one selected from the group consisting of rosin . The natural rosin and the stabilized rosin may be purified (recrystallized or the like) ( purified rosin ) . The rosins are preferably those having 3 or less colors according to the Gardner colorimetric method (JISK0071-2). As rosins, hydrogenated rosins are preferred. Such rosins include, as resin acids, abietic acid, neoabietic acid, dehydroabietic acid, parastrinic acid, levopimaric acid, pimaric acid, isopimaric acid, sandaracopimaric acid, tetrahydroabietic acid, dehydroabietic acid, and dihydro Abietic acid and the like are included.

Specifically, the hemiacetal esterification reaction is usually performed by, for example, converting a (meth) acryloyl group-containing monovinyl ether compound and rosin to about 30 to 150 ° C. in the presence or absence of a catalyst and a radical polymerization inhibitor ( Preferably 50 to 120 ° C.), usually 10 minutes to 6 hours (preferably 20 minutes to 5 hours). Moreover, you may use the below-mentioned organic solvent in the case of reaction.

  The amount of both raw materials used is not particularly limited, but from the stoichiometric point of view, the vinyl ether group of the (meth) acryloyl group-containing monovinyl ether compound is usually 0.5 to 1 mol per mol of the carboxyl group of the rosin. The range is preferably about 3.0 mol (preferably 1.0 to 2.0 mol).

  Specific examples of the catalyst include phosphate ester acid catalysts such as di-n-butyl phosphate, 2-ethylhexyl phosphate, and monooctyl phosphate. The amount used is not particularly limited, but is usually about 0.01 to 3 parts by weight (preferably 0.1 to 1.5 parts by weight) with respect to a total of 100 parts by weight of the raw material constituting the component (a-1). Part).

Specific examples of the radical polymerization inhibitor include quinone polymerization inhibitors [methoquinone, hydroquinone, methoxyhydroquinone, etc.], amine polymerization inhibitors [alkylated diphenylamine, N, N′-diphenyl-p-phenylenediamine, and the like. , Phenothiazine and the like], and the like. These can be used alone or in combination of two or more. Moreover, the usage-amount is although it does not specifically limit, Usually, it is the range of about 0.0005 to 0.5 weight part with respect to a total of 100 weight part of the raw material which makes (a-1) component. Further, together with the radical polymerization inhibitor, polymerization inhibition means such as air bubbling can be employed.

  Various purification treatments (filtration, distillation, solvent extraction, column separation, reprecipitation, etc.) can be applied to the component (a-1) thus obtained as necessary.

The component (a-2) copolymerizing with the component (a-1) includes one styrene selected from the group consisting of styrene, α-methylstyrene, t-butylstyrene and dimethylstyrene , and acryloylmorpholine. In addition, α, β unsaturated carboxylic acids ((meth) acrylic acid, maleic acid, maleic anhydride, maleic acid half ester, itaconic acid, itaconic anhydride, etc.) About 18 (meth) acrylic acid alkyl esters [methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, etc.] may be included.

Although the weight ratio of the component (a-1) and the component (a-2) is not particularly limited, it is usually preferably about 30/70 to 70/30.

The copolymerization reaction (specifically, radical polymerization reaction) is carried out in the presence or absence of various polymerization initiators, chain transfer agents and organic solvents, and both components are usually at a temperature of 100 to 150 ° C. for 30 to 3 hours. What is necessary is just to make it react to the extent.

  Specific examples of the polymerization initiator include azo compounds [2,2′-azobis (2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyrate, etc.], inorganic peroxides, and the like. Such as hydrogen peroxide, ammonium persulfate, potassium persulfate, etc., organic peroxides [t-butylperoxybenzoate, dicumyl peroxide, lauryl peroxide, etc.], etc. Or in combination of two or more. Although the usage-amount is not specifically limited, Usually, it is about 0.01-5 weight part with respect to a total of 100 weight part of (a-1) component and (a-2) component.

  The chain transfer agent can be used for the purpose of adjusting the molecular weight of the component (A), and examples thereof include dodecyl mercaptan, 2-mercaptobenzothiazole, bromotrichloromethane, and the like. Two or more kinds can be used in combination. Although the usage-amount is not specifically limited, Usually, it is about 0.01-5 weight part with respect to a total of 100 weight part of (a-1) component and (a-2) component.

  Specific examples of the organic solvent include aromatic hydrocarbons (benzene, toluene, xylene, etc.), esters (methyl acetate, ethyl acetate, propyl acetate, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone). Etc.], and these can be used alone or in combination of two or more.

  A purification process (reprecipitation etc.) can also be applied to the component (A) obtained in this way, if necessary.

  Although the physical property of (A) component is not specifically limited, Usually, a softening point is about 70-150 degreeC, and a weight average molecular weight (The polystyrene conversion value by a gel permeation chromatography) is about 1,000-10,000.

The rosin emulsion of the present invention is obtained by dispersing the component (A). Although the manufacturing method is not particularly limited, specifically, for example, it can be obtained by emulsifying component (A) in the presence of an emulsifier and water.

The emulsifying method is not particularly limited, and various known methods (high pressure emulsification method, inversion emulsification method, etc.) can be adopted. For example, in the case of the high-pressure emulsification method, the component (A) is dissolved in an organic solvent (benzene, toluene, etc.), and then forcibly emulsified using various known high-pressure emulsifiers in the presence of an emulsifier and water, The solvent may be removed under reduced pressure.

Examples of the emulsifier include an anionic emulsifier (α-olefin sulfonated product, alkyl sulfate, alkylphenyl sulfate, polyoxyethylene alkylphenyl ether sulfate, polyoxyethylene aralkyl phenyl ether sulfosuccinic acid half ester salt, etc.), nonionic emulsifier Oxyethylene alkylphenyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sorbitan fatty acid ester and the like], and the like can be used alone or in combination of two or more. Moreover, although the usage-amount of an emulsifier is not specifically limited, Usually, it is about 1-10 weight part in conversion of solid content with respect to 100 weight part of (A) component, Preferably it is 1-5 weight part. Further, as the water, city water, deionized water, ion exchange water, soft water, or the like can be used.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to this.

<Synthesis of (a-1) Component>
Hydrogenated rosin (mainly containing dehydroabietic acid, dihydroabietic acid, and tetrahydroabietic acid as resin acids) 150 g, Arakawa Chemical Industries, Ltd., 300 ml flask equipped with a water pipe, phenothiazine, phenothiazine 0.23 g was charged, and the reaction system was heated to 120 ° C. with stirring to melt them. Subsequently, 82.9 g of 2- (vinyloxyethoxy) ethyl acrylate (trade name “VEEA”, manufactured by Nippon Shokubai Co., Ltd.) was dropped into the reaction system in 15 minutes from the dropping funnel, and then 2-phosphoric acid 2- Ethylhexyl (trade name “AP-8”, manufactured by Daihachi Chemical Industry Co., Ltd.) (0.15 g) was charged, and kept at 100 ° C. for 1 hour to obtain an acryloyl group-containing rosin derivative.

<Production of rosin copolymer (A)>
In a reaction vessel equipped with a stirrer, a cooling tube, a dropping funnel and a nitrogen introducing tube, 90 parts of xylene was charged and the temperature was raised to about 133 ° C. Next, from the dropping funnel, 25 parts of the acryloyl group-containing rosin derivative, 65 parts of styrene, 10 parts of acryloylmorpholine, 2,2′-azobis (2-methylbutyronitrile) (trade name “ABN-E”, Inc. A mixed liquid consisting of 3.5 parts of Nippon Finechem) and 10 parts of xylene was added dropwise over 1.5 hours. Next, after cooling the reaction system to room temperature, 400 parts of hexane was added and stirred for 30 minutes. Subsequently, the rosin copolymer (A) was separated by decantation and dried at 100 ° C. for 2 hours and then at 90 ° C. for 2 hours. The rosin copolymer had a softening point of 97.5 ° C. and a weight average molecular weight of 9,400 (measuring instrument: product name “HLC-8120GPC”, manufactured by Tosoh Corporation).

<Manufacture of rosin emulsion>
Example 1
100 parts of rosin copolymer (A) was dissolved in 60 parts of toluene at 100 ° C. for about 1 hour, then cooled to 80 ° C., and 3 parts of an anionic emulsifier (sodium dodecylbenzenesulfonate) and 160 parts of water were added. The mixture was added and stirred vigorously at 75 ° C. for 1 hour to carry out preliminary emulsification. The obtained preliminary emulsion was high-pressure emulsified with a high-pressure emulsifier (mantongaurin) at a pressure of 29.4 MPa to obtain an emulsion. Next, 200 parts of the emulsion was charged in a vacuum distillation apparatus, and vacuum distillation was performed for 6 hours under the conditions of 50 ° C. and 133 hPa to obtain a rosin emulsion having a solid content of 50%.

Claims (1)

A (meth) acryloyl group-containing monovinyl ether compound and a rosin derivative obtained by subjecting one rosin selected from the group consisting of gum rosin, tall oil rosin, wood rosin, hydrogenated rosin and disproportionated rosin to hemiacetal esterification (a -1), styrene, alpha-methyl styrene, t- butyl styrene and one styrenes selected from the group consisting of dimethyl styrene and acrylic monofunctional vinyl compounds containing acryloyl morpholine (a-2) and is co-polymerization A rosin emulsion obtained by dispersing the rosin copolymer (A).