JP2002011337A - Emulsifying dispersant for aqueous emulsion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous emulsion excellent in emulsion stability without using an alkylphenol derivative type dispersant having a doubt of an endocrine disrupting substance and to effectively ensure adhesive capacity when the aqueous emulsion is used as a tackifier. SOLUTION: An emulsifying dispersant for the aqueous emulsion contains a sulfate ester salt of polyoxyalkylene rosin ester, which is obtained by adding alkylene oxide to rosins and subjecting the obtained adduct to sulfation and neutralization reaction, as an effective component. A resin emulsion obtained using this rosin ester type emulsifying dispersant is excellent in dispersibility and mechanical stability. When a rosin resin is emulsified as a tackifier resin by the emulsifying dispersant, the capacity of an aqueous adhesive is by no means inferior to a case using a conventional alkylphenol derivative.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emulsifying and dispersing agent for an aqueous emulsion containing no endocrine disrupting substance, and an aqueous emulsion using the emulsifying and dispersing agent, in particular, an aqueous emulsion using a rosin resin as a tackifier. With regard to
Provided is an aqueous emulsion which is excellent in storage stability and mechanical stability, and which can effectively secure the adhesive performance of an aqueous emulsion type adhesive.

[0002]

BACKGROUND OF THE INVENTION Conventionally, rosins and rosin derivatives have been
Paper sizing agents, tackifiers for adhesives, emulsifiers for rubber,
It is used in a wide range of fields as a paint modifier or a resin for printing ink. In recent years, in these fields, from the viewpoints of work safety and prevention of environmental pollution, aqueous emulsions that do not use organic solvents and the like have been developed, and various types of emulsion products have been put on the market. For example, in the field of aqueous emulsion-type pressure-sensitive adhesives used for various pressure-sensitive adhesive tapes, pressure-sensitive adhesive sheets, and pressure-sensitive adhesive labels, adhesive properties are improved by adding a water-based emulsion of a tackifier to a base polymer emulsion such as an acrylic emulsion or a rubber latex. For improving the adhesive properties, the type of the rosin-based resin as the object to be dispersed or the type of the emulsifying dispersant used in the aqueous emulsion is an important factor.

As an emulsifying dispersant for dispersing the rosin-based resin in water, various nonionic dispersants, high-molecular anionic dispersants, and cationic dispersants are used. From the viewpoint of the mechanical stability of the emulsion, in particular, polyoxyalkylene alkyls such as sodium polyoxyethylene nonylphenyl ether sulfate, ammonium polyoxyethylene nonyl ether sulfate, sodium polyoxyethylene octyl phenyl ether sulfate, and ammonium polyoxyethylene octyl phenyl ether sulfate Preference is given to sulfates of phenyl ether or a combination of these sulfates with any other dispersant.

[0004]

2. Description of the Related Art For example, as represented by the above-mentioned sulfate salts of polyoxyalkylene alkylphenyl ethers,
Conventional techniques using an alkylphenol derivative for emulsification of rosin include the following.

(1) Prior art 1 (Japanese Patent Application Laid-Open No. 52-77206) An aqueous solution obtained by inverting the emulsion of a reinforced rosin containing a sulfate of polyoxyethylene alkyl phenyl ether as an emulsifying dispersant. A rosin emulsion is disclosed.

(2) Prior art 2 (Japanese Patent Publication No. 58-4938) Using an alkylphenol derivative such as sodium 2-hydroxy-3- (distyrylphenoxypolyoxyethylene) propylsulfonate as an emulsifying dispersant, phase inversion is carried out. An aqueous emulsion of rosin obtained by the method is disclosed.

(3) Prior art 3 (Japanese Patent Application Laid-Open No. 4-145130), including a specific aryl group having four or more benzene rings,
An aqueous emulsion of a tackifier resin such as rosin obtained by a phase inversion method using a sulfated salt of a polyoxyalkylene aryl ether as an emulsifying dispersant is disclosed.

[0008]

As described above, emulsifying and dispersing agents used when an aqueous emulsion of a tackifier resin or the like is used include alkylphenol derivatives represented by polyalkylene alkylphenyl ether sulfates. However, in recent years, this type of alkyl phenol derivative has been strongly pointed out as an endocrine disrupting substance, and there is an increasing demand for tighter regulation.
Therefore, various compounds that do not use alkylphenol derivatives, such as linear alkyl type, are currently being developed as emulsifying dispersants that can effectively disperse rosin-based resins, but dispersibility in water and mechanical stability of emulsions are being promoted. In terms of properties and the like, the fact is that it is lower than that of alkylphenol derivatives.

[0009] The present invention provides an aqueous rosin resin which does not use an alkylphenol derivative which is suspected of being an endocrine disrupting substance, is excellent in the dispersibility of a rosin resin in water, the mechanical stability of an emulsion, and the like. It is another technical object of the present invention to develop a new emulsifying and dispersing agent which is comparable to the above-mentioned alkylphenol derivatives in terms of adhesion performance when an emulsion is applied to a tackifier.

[0010]

When a rosin-based resin or the like is converted into an aqueous emulsion, the above-mentioned sulfate salt of polyoxyalkylene alkylphenyl ether exhibits particularly excellent emulsifying and dispersing power. It was presumed that a combination of a benzene skeleton and an alkylene oxide chain among the above compounds greatly contributed to the dispersing power.

On the other hand, the present applicant has previously disclosed in Japanese Patent Laid-Open No. 53-5 / 78.
Japanese Patent No. 8509 (hereinafter referred to as Prior Art 1) discloses a liquid detergent composition containing a polyethylene glycol ester of rosin as a main component for the purpose of improving biodegradability and detergency against oily stains and realizing low foamability. Disclosed. Japanese Patent Application Laid-Open No. 57-51744 (hereinafter referred to as Prior Art 2) discloses a technique for realizing excellent tackifying properties and wide compatibility with a base polymer, and making it applicable to an emulsion adhesive. A liquid tackifier containing a polyalkylene glycol ester of rosin as a main component is disclosed.

According to the above prior art 1, the polyethylene glycol ester of rosin exhibits a good detergency when applied to a general detergent application. Of replacing the benzene skeleton portion of the polyoxyalkylene alkylphenyl ether sulfate salt from alkylphenols with rosins which are natural products and contain various active sites such as carboxyl groups in the condensed benzene ring. Inspired. Then, instead of utilizing the alkylene oxide adduct of rosin as a tackifier as in the above-mentioned prior art 2, the intense research was focused on its use as an emulsifying dispersant when emulsifying a rosin-based resin or the like. As a result, the dispersing ability of the rosin alkylene oxide adduct itself is not so expected in terms of emulsifying the rosin resin, but when the adduct is sulfated, the dispersing power and the mechanical stability of the emulsion are dramatically improved. It has been found that when the rosin emulsion dispersed with the sulfate ester is used as an aqueous tackifier, the rosin emulsion exhibits an adhesive performance comparable to that of the alkylphenol derivative-type dispersant. Was completed.

That is, the present invention 1 is a sulfate ester of a polyoxyalkylene rosin ester represented by the following general formula (a) obtained by adding an alkylene oxide to a rosin-based resin, and performing a sulfation and neutralization reaction. Salt R-COO (AO) _n SO ₃ M (a) (wherein RCOO is a rosin residue; A is C ₂ -C
_{4 is} an alkylene group or a substituted alkylene group; n is an integer from 1 to 1000; M is an alkali metal, alkaline earth metal, ammonia or amine. ) As an active ingredient.

The present invention 2 is the invention according to the above-mentioned invention 1, wherein the addition mole number of the alkylene oxide to the rosin is 1 to 5
0 is an emulsifying dispersant for an aqueous emulsion.

[0015] The present invention 3 is an aqueous emulsion characterized in that a resin is dispersed in water in the presence of the emulsifying dispersant of the present invention 1 or 2.

[0016] The present invention 4 is an aqueous rosin emulsion, wherein the resin of the present invention 3 is a rosin resin.

According to a fifth aspect of the present invention, in the fourth aspect, the content of the emulsifying dispersant with respect to the rosin resin is 1 to 10% by weight.
An aqueous rosin emulsion is characterized in that:

A sixth aspect of the present invention is an aqueous tackifier emulsion, wherein the resin according to any one of the third to fifth aspects is a tackifier resin.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to an emulsifying dispersant comprising a compound obtained by subjecting an alkylene oxide adduct of a rosin to sulfation and neutralization, and secondly, using this emulsifying dispersant. It is an aqueous emulsion in which a resin such as rosin is dispersed in water, and the third is an aqueous tackifier emulsion in which the resin such as rosin is used as a tackifier resin.

The present invention 1 is a rosin ester-type polyoxyalkylene sulfate ester salt obtained by subjecting a rosin-based resin to an alkylene oxide to undergo an addition reaction and sulfate-sulphurizing the adduct and alkali-neutralizing the rosin-based resin. Rosins and various rosin derivatives can be used alone or in combination for the resin. The rosins are abietic acid, parastolic acid, neoabietic acid, pimaric acid, isopimaric acid,
Alternatively, unmodified rosins such as tall oil rosin, gum rosin, wood rosin, and the like, which are mainly composed of resin acids such as dehydroabietic acid, disproportionated rosins, polymerized rosins, hydrogenated rosins, or other chemically modified rosins And so on.

Examples of the rosin derivative include rosin esters, formalin-modified rosins, unsaturated carboxylic acid-modified rosins, and phenol-modified rosins.
The rosin esters are those obtained by reacting rosins with alcohols by a known esterification method. The esterification reaction is performed by heating the rosin-based resin and the alcohol to 200 to 300 ° C. in an atmosphere of an inert gas and removing generated water to the outside of the system. The mixing excess ratio of the alcohol with respect to the rosin is optional, but is generally preferably about 0.1 to 2.0. In the esterification, a known catalyst such as phosphoric acid, p-toluenesulfonic acid, lithium hydroxide, calcium hydroxide, magnesium oxide, zinc oxide, and calcium acetate can be used to promote the reaction. Examples of the alcohols include n-octyl alcohol, 2-ethylhexyl alcohol, decyl alcohol, lauryl alcohol, and stearyl alcohol.
Dihydric alcohols, ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, neopentyl glycol, trimethylene glycol, tetramethylene glycol, 1,3-butanediol, 1,6-hexanediol, etc. Alcohol, glycerin, trimethylolpropane, trimethylolpropane, trimethylolethane, trihydric alcohol such as triethylolethane, tetrahydric alcohol such as pentaerythritol and diglycerin, or hexahydric alcohol such as dipentaerythritol and sorbitol. Can be used alone or in combination. Glycerin, pentaerythritol and the like are particularly preferred from the viewpoint of simplicity of the production process and economic efficiency.

The formalin-modified rosins are obtained by adding formalins to rosins. Examples of the formalins include formaldehyde, paraformaldehyde, trioxymethylene, and the like. From the viewpoint, paraformaldehyde is particularly preferred. In the addition reaction of the formalins, the rosin-based resin and the formalins are converted to 130 to 200 under an inert gas atmosphere.
It is carried out by a known method such as heating to ° C. The polymerization ratio of formaldehyde to rosin resin is 0.1 to 1
About 0% is preferable. This reaction proceeds relatively quickly, but in some cases, a known acid catalyst such as phosphoric acid or p-toluenesulfonic acid can be used.

The unsaturated carboxylic acid-modified rosins are obtained by reacting rosins with α, β-unsaturated carboxylic acids, and the α, β-unsaturated carboxylic acids are α, β-unsaturated carboxylic acids. Acids or acid anhydrides thereof, specifically, (anhydrous) maleic acid, fumaric acid, itaconic acid, (anhydrous)
Citraconic acid, acrylic acid, methacrylic acid and the like can be mentioned. The reaction between the rosin-based resin and the α, β-unsaturated carboxylic acid is carried out by a known method such as heating both to 150 to 280 ° C. in an inert gas atmosphere. The weight ratio of α, β-unsaturated carboxylic acid to rosin resin is 0.1.
About 20% is preferable.

The above-mentioned phenol-modified rosins are obtained by reacting rosins with phenol. In the presence of a strong acid catalyst such as sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid or the like, the rosins and phenol are reacted at 100 to 200 ° C. By reacting with In some cases, the strong acid catalyst may be neutralized with an alkaline substance such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and calcium hydroxide. The weight ratio of phenol to rosin resin is 0.1 to 5
About 0% is preferable.

The above formula (A) represents a general formula of a sulfate salt of a polyoxyalkylene rosin ester.
COO is a rosin residue, that is, a hydrocarbon group derived from rosins containing a carboxyl group, represented by an abietic acid skeleton. In this case, since the alkylene oxide basically adds to the carboxyl group in the rosin molecule with dehydration, it is important that the rosin resin used in the addition reaction has a carboxyl group in the rosin skeleton. Therefore, rosins and rosin derivatives such as unsaturated carboxylic acid-modified rosins are preferable, and rosin esters and the like require attention because the residual acid value is reduced by the reaction.

In the addition reaction with the rosin-based resin, C_Two~
C_FourAlkylene oxide, or C _Two~ C_FourReplacement al
Kylene oxide can be used. C_Two~ C_FourAlkylene oxy
Substituents of sides include methyl, ethyl, propyl, and hydroxyl.
Therefore, unsubstituted or substituted alkylene oxide
Specific examples of SID include ethylene oxide and propylene
Oxide (normal type, branched type), hydroxypropylene
Oxide, butylene oxide, isobutylene oxide
And ethylene oxide, propylene oxide
Is preferred. In the above addition reaction of the alkylene oxide,
Addition of multiple types of alkylene oxide to rosin resin
Is also good. For example, rosin-based resin
Tylene oxide and propylene oxide adducts
Includes multiple types of alkylene oxides in random permutations
Can be added.

The rosin alkylene oxide adducts include sulfuric acid, sulfur trioxide, chlorosulfonic acid, fuming sulfuric acid,
It is sulfated by a sulfating agent such as sulfamic acid and neutralized with an alkali such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, and various amines (eg, ethanolamines).

In the production of the rosin ester type polyoxyalkylene sulfate salt of the present invention 1, 150 to 250
The above-mentioned alkylene oxide is added to the rosin under the pressure of ° C., and the number of moles n added can be easily controlled by allowing n times equivalent of the above-mentioned alkylene oxide to coexist with the carboxyl group equivalent of the rosin in the reaction system. . The number of moles n of the alkylene oxide added to the rosin is from 1 to 1.
000, the dispersibility is reduced if the number of added moles is small,
If it is too large, the hydrophilicity becomes strong. Therefore, from the viewpoint of the dispersion power, the balance between hydrophilicity and hydrophobicity, or the viewpoint of the water resistance of the pressure-sensitive adhesive when the obtained aqueous emulsion is used as a tackifier, the preferred number of moles of the present invention As shown in FIG.

The present invention 3 is an aqueous emulsion obtained by dispersing various resins in water using the emulsifying dispersant of the present invention 1, and the present invention 4 is an aqueous rosin emulsion using this resin as a rosin resin. Invention 6 is an aqueous tackifier emulsion using this resin as a tackifier resin. The emulsifying dispersant of the present invention 1 can be applied to various resins including a rosin-based resin. For example, a rosin-based resin as a tackifier resin as a dispersion object of the tackifier emulsion of the present invention 6 is used. Resins, α-pinene obtained from raw materials such as rosin and citrus, β-pinene, monocyclic terpenes such as dipentene, or a terpene resin obtained as a (co) polymer of the terpene and styrene,
Dammar, copal, shellac, olefins in the distillate at the time of cracking of petroleum feedstock, diolefins, or aromatic compounds, mainly of C ₅ -C ₉ Compound (co) petroleum resins obtained by polymerization, coumarone - indene Resins.

Various resins including a rosin-based resin are:
In the presence of the emulsifying dispersant of the present invention 1, an aqueous emulsion can be formed by a solvent emulsification method, a solventless emulsification method, a phase inversion emulsification method, or other known methods. In the solvent-type emulsification method, various resins are dissolved in an organic solvent such as toluene, benzene, or methylene chloride, and the cationic resin solution and water are premixed to prepare an aqueous emulsion of coarse particles. Fine emulsification in the same way using a machine,
This is a method for removing the organic solvent. The solvent-free emulsification method is a method in which various kinds of molten resin, the above-mentioned cationic resin solution and water are pre-mixed to prepare an aqueous emulsion of coarse particles, and then various mixers, a homogenizer, a colloid emulsifier, a high-pressure emulsifier, and the like. This is a method of finely dispersing by using. The phase inversion emulsification method is a method of sufficiently kneading various resins and the above cationic resin solution, gradually adding water while stirring, and inverting the water-in-oil emulsion to an oil-in-water emulsion. .

When a rosin-based resin is emulsified by using the emulsified dispersant of the present invention 1, the amount of the emulsified dispersant used (in terms of solid content) with respect to the rosin-based resin depends on the emulsification stability and
From the viewpoint of satisfying the adhesive performance as a tackifier, it is 1 to 10% by weight, preferably 3 to 7% by weight.
(See Invention 5). If the amount is too small, the dispersibility decreases, and if it is too large, the water resistance as an adhesive when a rosin emulsion is used as a tackifier may decrease.

The resin emulsion using the rosin ester type emulsifying dispersant of the present invention 1 is first suitable as the above-mentioned tackifier emulsion. Therefore, an aqueous adhesive can be easily produced by mixing this tackifier emulsion with a base polymer emulsion such as an acrylic emulsion or a rubber latex. In addition, resin emulsions using the emulsifying dispersant of the present invention 1, particularly rosin emulsions, include aqueous emulsion type sizing agents,
It can be effectively used for various uses such as rubber emulsifier and paint modifier.

[0033]

(1) The rosin ester type emulsifying dispersant of the present invention has a rosin skeleton in which an alkylene oxide chain is bonded and a sulfate ester structure is located at the terminal of the chain. Since various surface active functions can be expected, various resins including rosin-based resins can be satisfactorily emulsified. That is, as shown in the test examples described below, emulsions using the emulsifying dispersant of the present invention, linear alkyl type dispersant, and the prior art 1 ~
As compared with the emulsion using an alkylene oxide adduct of a rosin described in 2, the particle size is small, the storage stability and the mechanical stability are good, and it is comparable to the case where an alkylphenol derivative type dispersant is used. Demonstrates emulsion performance. Particularly, so-called alkylene oxide adducts of rosins belonging to nonionic dispersants are used for general detergents or tackifiers in the above-mentioned prior arts 1 and 2, but in the present invention, this alkylene oxide adduct is used. Is used as an emulsifying dispersant when a rosin-based resin or the like is emulsified. And
In the emulsion performance, it should be noted that the emulsifying dispersant of the present invention, which is a sulfate compound, is significantly superior to the alkylene oxide adduct of rosin.

The water-based pressure-sensitive adhesive using the above-mentioned rosin emulsion as a tackifier has an adhesive force to a stainless steel plate and an adhesive force to a polypropylene plate even when a conventional alkylphenol derivative type dispersant is used. As a result, there is no inferiority in holding force to the stainless steel plate or tackiness (see the test examples described later), and it is possible to effectively exhibit a practical level or higher adhesive performance.

(2) The emulsifying dispersant of the present invention comprises a rosin ester-type polyoxyalkylene sulfate ester obtained from natural rosin as a raw material, and an alkylphenol having a strong suspicion of an endocrine disrupting substance as a reactant. Because they are not used, they are extremely safe for living organisms and can effectively prevent environmental pollution.

[0036]

EXAMPLES Examples of the production of a rosin ester type emulsifying dispersant, examples of the production of various rosin derivatives, and examples of a rosin emulsion in which the rosin derivative is dispersed in water with the above emulsifying dispersant will be sequentially described. A description will be given of a property test example and a performance evaluation test example of a pressure-sensitive adhesive obtained by mixing a rosin emulsion as a tackifier with an acrylic polymer emulsion base. It should be noted that the present invention is not limited to the following examples and test examples, and it is needless to say that any modifications can be made within the technical idea of the present invention. Further, “parts” and “%” in each of Production Examples, Examples, and Test Examples are based on weight unless otherwise specified.

<< Examples of Production of Rosin Ester Type Emulsifying Dispersant >> First, an addition reaction of disproportionated rosin with ethylene oxide was carried out, followed by sulfation and neutralization. State. In Production Examples 1 and 2, differences were provided in the number of moles of ethylene oxide added to disproportionated rosin. Production Example 3 is a product obtained by terminating the reaction in the step of adding disproportionated rosin and ethylene oxide without performing the latter half of the sulfation and neutralization treatments. This is an example.

Production Example 1 100 parts of purified disproportionated tall rosin having an acid value of 170 and 1 part of potassium hydroxide as a reaction catalyst were placed in a pressure-resistant reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction pipe, a gas introduction pipe, and a cooling pipe. In a nitrogen stream.
The temperature was raised to ° C. to melt the rosin. And 0
200 parts of ethylene oxide gas heated to 70 ° C. was gradually introduced into the reaction vessel to perform an addition reaction. Next, the obtained addition product was cooled to 50 ° C., and sulfur trioxide gas 2
Five parts were gradually introduced into the reaction vessel to carry out a sulfation reaction, neutralized and diluted with an equivalent amount of an aqueous sodium hydroxide solution, to give a solid content of 30.0% and an ethylene oxide addition rate of 15%.
mol of emulsifying dispersant 1 was obtained.

<< Production Example 2 >> 100 parts of purified disproportionated tall rosin having an acid value of 170 and 1 part of potassium hydroxide as a reaction catalyst were placed in a pressure-resistant reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction pipe, a gas introduction pipe, and a cooling pipe. In a nitrogen stream.
The temperature was raised to ° C. to melt the rosin. 400 parts of ethylene oxide gas heated to 0 to 70 ° C. was gradually introduced into the reaction vessel to perform an addition reaction. Next, the obtained addition product is cooled to 50 ° C., and 25 parts of sulfur trioxide gas is gradually introduced into the reaction vessel to perform a sulfation reaction, and neutralization and dilution are performed with an equivalent amount of an aqueous sodium hydroxide solution. And solid content 3
An emulsifying dispersant 2 having 0.0% of an ethylene oxide addition rate of 30 mol was obtained.

<< Production Example 3 >> In a pressure-resistant reaction vessel equipped with a stirrer, thermometer, nitrogen introduction pipe, gas introduction pipe, and cooling pipe, 100 parts of purified disproportionated tall rosin having an acid value of 170 and 1 part of potassium hydroxide as a reaction catalyst In a nitrogen stream.
The temperature was raised to ° C. to melt the rosin. Then 0-70
400 parts of ethylene oxide gas heated to 400 ° C. was gradually introduced into the reaction vessel to carry out an addition reaction, and then diluted with soft water to give a solid content of 30.0% and an ethylene oxide addition rate of 30 m.
ol emulsifying dispersant 5 was obtained.

<< Examples of Production of Various Rosin Derivatives as Tackifier Resins >> Then, Examples A to D of production of rosin derivatives as the dispersion target will be described for each type. Production Example A is a rosin ester, Production Example B is a polymerized rosin ester, Production Example C
Is an example of an acrylic-modified rosin ester, and Production Example D is an example of a phenol-modified rosin.

<< Production Example A >> Chinese gum rosin 1 was placed in a reaction vessel equipped with a stirrer, thermometer, nitrogen inlet tube, and drain tube.
And then melted under a nitrogen stream to obtain 160 parts.
At 10 ° C., 10 g of pentaerythritol was added, and the temperature was raised to 275 ° C. over 3 hours with stirring. Then 27
The reaction was continued at 5 ° C. to obtain a tackifier resin composed of a rosin ester having an acid value of 15 and a softening point of 103 ° C.

<< Production Example B >> Chinese gum rosin 5 was placed in a reaction vessel equipped with a stirrer, thermometer, nitrogen introduction pipe, and drain pipe.
0 parts and 50 parts of a polymerized gum rosin produced in China were charged, melted under a nitrogen stream, 10 g of pentaerythritol was added at 160 ° C., and the temperature was raised to 275 ° C. over 3 hours with stirring. Then, the reaction was continued at 275 ° C. to obtain a tackifier resin comprising a polymerized rosin ester having an acid value of 10 and a softening point of 133 ° C.

<< Production Example C >> Chinese gum rosin 1 was placed in a reaction vessel equipped with a stirrer, thermometer, nitrogen inlet tube, and drain tube.
And then melted under a nitrogen stream to obtain 160 parts.
5 g of acrylic acid is added at 200 ° C. and 200 ° C. while stirring.
And the reaction was continued for 2 hours. Next, 15 g of pentaerythritol was added, and the temperature was raised to 275 ° C. over 3 hours with stirring. Next, the reaction was continued at 275 ° C. to obtain a tackifier resin composed of an acrylic-modified rosin ester having an acid value of 10 and a softening point of 120 ° C.

<< Production Example D >> Chinese gum rosin 1 was placed in a reaction vessel equipped with a stirrer, thermometer, nitrogen inlet tube, and drain tube.
And then melted under a stream of nitrogen to obtain 150 parts.
At 30 ° C., 30 g of phenol and 0.1 g of p-toluenesulfonic acid were added.
One part was added and reacted for 5 hours with stirring. Then, after adding an aqueous solution of lithium hydroxide so that the pH in the reaction system becomes 5 or more, 27 hours are added with stirring for 3 hours.
The temperature was raised to 5 ° C. The reaction was continued at 275 ° C. to obtain a tackifier resin composed of phenol-modified rosin having an acid value of 95 and a softening point of 127 ° C.

<< Production Examples of Rosin Emulsion >> Therefore, a rosin emulsion is produced by mixing the emulsifying dispersants 1-2 obtained in Production Examples 1-2 and the various rosin derivatives obtained in Production Examples AD. did. That is, 100 parts of the solid rosin derivative obtained in Production Examples A to D are dissolved in 60 parts of toluene, and 3 parts of each emulsifying dispersant 1 to 2 obtained in Production Examples 1 to 2 (solid content conversion). ) Was previously dissolved in 117 parts of soft water, and emulsified water was added to the rosin derivative solution.
This mixture was pre-emulsified with a homomixer, passed through a high-pressure emulsifier adjusted to a discharge pressure of 300 kg / cm ² and emulsified, and then toluene was removed from the obtained emulsion at 50 ° C. under reduced pressure. Aqueous rosin emulsions having a solid content of 50% were produced, and Examples 1 to 8 were prepared.

On the other hand, sodium polyoxyethylene nonylphenyl ether sulfate (ethylene glycol addition rate: 10 mol) as an alkylphenol derivative was used as emulsifying dispersant 3, and sodium polyoxyethylene lauryl ether sulfate (ethylene glycol addition rate: 30 mol) as a higher alcohol derivative. As emulsifying dispersant 4, and
A rosin emulsion was prepared by mixing the rosin ethylene oxide adduct obtained in Production Example 3 with an emulsifying dispersant 5 and mixing these emulsifying dispersants 3 to 5 with various rosin derivatives of Production Examples A to D. And Comparative Examples 1 to 8, respectively. The left two columns in FIG. 1 show Example 1 in which the rosin derivatives of Production Examples A to D were dispersed in water using emulsifying dispersants 1 to 5.
8 summarizes the details of each rosin emulsion of Comparative Examples 1 to 8.

<< Various Test Examples of Rosin Emulsion >> Therefore, various tests of the particle diameter, storage stability and mechanical stability were performed for each of the rosin emulsions of Examples 1 to 8 and Comparative Examples 1 to 8. The particle size of the above emulsion was measured by a dynamic light scattering method using DLS-700 manufactured by Otsuka Electronics Co., Ltd. Regarding the storage stability, the emulsion was stored in a closed container in an atmosphere at 23 ° C., and the presence or absence of water separation of the emulsion was observed for one month. The evaluation criteria are as follows. ○: Even after storage for one month, the emulsion did not separate. Δ: The emulsion separated from water within 10 days or more and less than 1 month. ×: The emulsion was separated in less than 10 days. The mechanical stability was determined by collecting 50 g of the emulsion in a container of Marlon-type stability tester (manufactured by Kumagaya Riki Kogyo Co., Ltd.)
After adding a mechanical shear for 5 minutes under the conditions of 5 ° C., a load of 10 kg, and a rotation speed of 1000 rpm, the formed aggregate is
It was filtered through a 00 mesh wire net, the dry weight of the aggregate was calculated with respect to the initial dry weight of the emulsion, and the mechanical stability was evaluated based on the formation rate (%) of the aggregate.

The three columns on the right in FIG. 1 show the test results.
In Examples 1 to 8 using the rosin ester type emulsifying dispersant, the particle diameter was small, the storage stability and the mechanical stability were evaluated well, and Comparative Examples 1 to 4 using the nonylphenol derivative type dispersing agent were used. It was a level similar to. Moreover, when the rosin ester type emulsifying dispersant of the present invention is used, they can be satisfactorily formed into an aqueous emulsion regardless of the type of the rosin derivative. Therefore, it has been clarified that the emulsifying dispersant of the present invention can smoothly emulsify various rosin derivatives at a level that can be substituted for the nonylphenol derivative which is highly suspected of being an endocrine disrupting substance. In addition, Comparative Examples 5 to 6 of the linear alkyl dispersant had a large particle size, poor storage stability, and poor mechanical stability.
Compared to 6, the rosin emulsions of Examples 1 to 8
It can be seen that the evaluation of the particle size, storage stability, or mechanical stability has been greatly improved. Further, in the ethylene oxide adducts of rosins of Comparative Examples 7 to 8 (comparative examples of the above-mentioned prior arts 1 and 2), all of the evaluations of particle size, storage stability and mechanical stability were performed in Comparative Examples 5 to 5. Worse than 6, Examples 1 to
The evaluation was even lower than that of No. 8. Therefore, by comparing the emulsifying dispersants of Examples 1 to 8 with those of Comparative Examples 7 and 8, the remarkable superiority of sulphating ethylene oxide adducts of rosins with sulfuric acid ester in terms of dispersion performance is clearly shown. Supported.

Thus, the rosin emulsions of Examples 1 to 4 and Comparative Examples 1 to 4 which showed good emulsion evaluations from the above test examples were extracted, and these rosin emulsions were used in aqueous pressure-sensitive type using a tackifier. An adhesive was manufactured and its adhesive performance was evaluated.

<< Production Example of Water-Based Pressure-Sensitive Adhesive >> A reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, a nitrogen inlet tube, and a cooling tube was charged with 60 parts of soft water and heated to 80 ° C. under a nitrogen stream. Next, in a mixed monomer of 97 parts of 2-ethylhexyl acrylate and 3 parts of methacrylic acid, 3 parts of sodium polyoxyethylene oleyl ether sulfate and 0.5 part of potassium persulfate as a polymerization initiator were dissolved in 35 parts of soft water. Emulsified water was added, these mixed monomers were emulsified with a homomixer, and the emulsion was dropped into a reaction vessel at 80 ° C. over 3 hours using a dropping funnel. afterwards,
The polymerization was completed by maintaining the temperature at 80 ° C. for 1 hour, and after cooling to room temperature, the mixture was filtered through a 200-mesh wire gauze to obtain a solid content of 5%.
An aqueous acrylic polymer emulsion having a particle size of 0.3%, a particle diameter of 0.35 μm, and a pH of 2.0 was obtained. The aqueous acrylic polymer emulsion was used as a base polymer emulsion, and 20 parts of the aqueous emulsion tackifiers of Examples 1 to 4 and Comparative Examples 1 to 4 were added to 100 parts of the emulsion base. 1 part of an acid thickener (ASE-60; manufactured by Rohm and Haas Japan), and 28% aqueous ammonia as a pH adjuster.
By adding 5 parts of each, an aqueous pressure-sensitive adhesive was produced.

Next, a pressure-sensitive adhesive tape was trial-produced using each of the above-mentioned water-based pressure-sensitive adhesives, using the rosin ester type emulsifying dispersant of the present invention and the conventional sodium polyoxyethylene nonylphenyl ether sulfate. The adhesive performance was evaluated by comparing the cases. Further, an aqueous pressure-sensitive adhesive was produced using only the base polymer emulsion without adding the aqueous emulsion tackifier, and this was designated as Comparative Example 9.

<< Performance evaluation test example of water-based pressure-sensitive adhesive >> A polyester film (Lumirror film; manufactured by Toray Co., Ltd.) having a thickness of 25 μm was placed on the above Examples 1-4 and Comparative Example 1.
The water-based pressure-sensitive adhesive using the emulsions of Nos. 1 to 4 as a tackifier, or the water-based pressure-sensitive adhesive of Comparative Example 9 using no tackifier, so that the coating thickness after drying becomes 25 μm. After coating with an applicator, each was dried with a hot-air dryer at 110 ° C. for 3 minutes to obtain a film-like test piece. Then, the test piece was stored in a thermo-hygrostat at a temperature of 20 ° C. and a relative humidity of 65% for 2 days and subjected to a performance evaluation test.

Various performance evaluation methods are as follows. (1) Adhesive strength to stainless steel plate (SUS adhesive strength) In accordance with JIS Z-0237, using a stainless steel plate whose surface has been polished with SUS 304 with 280th abrasive paper for the adherend, 180
The peel strength (unit: gf / 25 mm) when peeled at a speed of 300 mm / min in the degree direction was measured at a temperature of 20 ° C. and a relative humidity of 6
The measurement was performed under an atmosphere of 5%.

(2) Adhesive force against polypropylene plate (PP adhesive force) According to JIS Z-0237, the peel strength when peeling at a rate of 300 mm / min in the 180-degree direction using polypropylene as an adherend ( Unit: gf / 25 mm) at a temperature of 20 ° C.
The measurement was performed in an atmosphere with a relative humidity of 65%.

(3) Holding force against stainless steel plate (SUS holding force) In accordance with JIS Z-0327, a stainless steel plate obtained by polishing SUS 304 with No. 280 abrasive paper and surface-finishing was used for the adherend. The above test pieces of 25 mm × 25 mm were attached, and 1 k in the direction of gravity was applied in an atmosphere at a temperature of 40 ° C. and a relative humidity of 65%.
g of static load was applied, and the deviation width of the test piece 24 hours later was measured. When the test piece fell off the stainless steel plate by the end of the test, the time was measured.

(4) Tack In accordance with JIS Z-0237, each of the above test pieces was fixed on a slope having an inclination angle of 30 degrees, and 1/32 inch (steel ball No. 1) to 32/32 on the test piece. (Steel ball No. 32) Roll the steel ball of inch and stop on the adhesive surface.
The measurement was performed in an atmosphere at 0 ° C. and a relative humidity of 65%. In this test, the higher the steel ball number, the higher the evaluation.

FIG. 2 shows the test results. The adhesive using the rosin ester-type emulsifying dispersant of the present invention is different from the adhesive using the conventional alkylphenol derivative-type dispersing agent in that each of SUS adhesive strength, PP adhesive strength, SUS holding power and tackiness is used. The evaluation was comparable. Therefore, it has been clarified that the emulsions of various rosin derivatives using the emulsifying dispersant of the present invention, when applied to aqueous adhesive applications, provide a practical level or higher adhesive property modifying effect.

[Brief description of the drawings]

FIG. 1 is a table showing the test results of emulsion stability of aqueous rosin emulsions of Examples 1 to 8 and Comparative Examples 1 to 8.

FIG. 2 is a table showing the results of an adhesive performance evaluation test of an aqueous pressure-sensitive adhesive using each of the rosin emulsions of Examples 1 to 4 and Comparative Examples 1 to 4, and a base polymer emulsion of Comparative Example 9.

Continued on the front page F term (reference) 4D077 AA03 AA05 AA08 AB05 AB06 AB20 AC01 AC03 AC05 BA03 BA13 BA15 CA15 CA20 DA02Z DB07Z DC08Z DC19Y DC32Y DC54Y DD03Y DD32Y DD33Y DE09Y DE29Y 4J002 AF021 AF022 CH022 FD202 GJ01 A005A

Claims (6)

[Claims] 1. A rosin-based resin obtained by adding an alkylene oxide to a sulfonation and neutralization reaction and having the following general formula:
Sulfuric acid ester salt of polyoxyalkylene rosin ester represented by (A) R-COO (AO) _n SO ₃ M (A) (In the formula (A), RCOO is a rosin residue; A is C _2- C
_{4 is} an alkylene group or a substituted alkylene group; n is an integer from 1 to 1000; M is an alkali metal, alkaline earth metal, ammonia or amine. ) As an active ingredient. 2. The method according to claim 1, wherein the number of moles of the alkylene oxide added to the rosin is 1 to 50.
Emulsifying dispersant for aqueous emulsions. 3. An aqueous emulsion comprising a resin dispersed in water in the presence of the emulsifying dispersant of claim 1. 4. An aqueous rosin emulsion, wherein the resin according to claim 3 is a rosin resin. 5. The aqueous rosin emulsion according to claim 4, wherein the content of the emulsifying dispersant with respect to the rosin resin is 1 to 10% by weight. 6. A water-based tackifier emulsion, wherein the resin according to any one of claims 3 to 5 is a tackifier resin.