JP3396263B2 - Aqueous dispersion resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the storage of water-dispersed resins, for example, water-dispersed resins used in the fields of coated papers, paints, cosmetics, adhesives and the like. The present invention relates to an aqueous dispersion composition which improves stability and does not adversely affect the quality required in each field. 2. Description of the Related Art In recent years, regulations on the use of organic solvents have been tightened from the viewpoints of environmental problems such as air pollution and destruction of the ozone layer, and saving of petroleum resources. ing. In view of such regulation problems and handling operability, switching to a water-dilutable water-dispersible resin is increasing. However, the aqueous dispersion resin is obtained by dispersing synthetic resin particles in water, and often causes separation or aggregation when stored. The mechanism of separation and aggregation is roughly called sedimentation separation by gravity, aggregation separation by Van der Waals force, etc.In general, to remove these instability factors, reduce the particle diameter to increase Brownian motion, In order to eliminate the collision of particles, functional groups such as carboxylic acid are introduced into the particles to form an electric double layer to repel ions, to increase the hydrated layer by introducing nonionic groups, and to use a protective colloid agent Was the way. However, these may degrade the intended performance depending on the application and the method of use. As an example, in a synthetic rubber latex used for a coating composition for cast paper, when a carboxylic acid having a large storage stability effect is introduced into the particles, the releasability of the cast paper is reduced, resulting in impaired workability. . In the case of the plastic pigment in the coated paper composition, the physical properties of the coated paper are improved in a particle size range of 0.5 to 1 μm.
There are physical limitations on reducing the particle size, and there is a problem with storage stability. As described above, various methods for improving the storage stability have been studied, but they are not yet sufficient, and development of an aqueous dispersion resin composition having good storage stability has been demanded. [0003] The inventors of the present invention have conducted various studies on an aqueous dispersion resin composition having good storage stability, and as a result, by adding nitro alcohols to the aqueous dispersion resin. The inventors have found that storage stability is dramatically improved, and have completed the present invention. That is, the present invention provides a method in which a specific nitro alcohol compound is added to an aqueous dispersion resin in an amount of 10 to 5 times.
An aqueous dispersion resin composition characterized by containing 000 ppm. Hereinafter, the present invention will be described in detail. Examples of the aqueous dispersion resin include vinyl acetate emulsion, ethylene vinyl acetate emulsion, acrylic emulsion, synthetic rubber latex, and plastic pigment emulsion. or
The nitro alcohols used in the present invention include 2,2
2-dibromo-2-nitro-1-ethanol and 2-
Chloro-2-nitroethanol is preferred. The above compounds may be used alone or in combination. The addition of the nitro alcohol may be during or after the production process of the aqueous dispersion resin, and there is no limitation on the method of use. In the aqueous dispersion resin, known additives and the like may be used in combination, but the amount of nitro alcohol used is 10 to 5000 ppm, preferably 50 to 1 ppm based on the aqueous dispersion resin.
Should be in the range of 000 ppm, and the
pm or less, storage stability is not improved and 5000p
Use above pm does not improve storage stability. Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The aqueous dispersion resin used in the present invention was produced by the following method. Production Example of Water Dispersion Resin (Synthetic Rubber Latex) Production Example-1 Ion-exchange water 3
8.53 kg, sodium lauryl sulfate 0.38 kg,
And 3.02 kg of seed particles having an average particle size of 0.05 μ and a solid concentration of 25% by weight, 0.76 kg of potassium persulfate,
76 g of caustic potassium was charged and the inside of the system was replaced with nitrogen. Thereafter, 13.23 kg of butadiene, 24.57 kg of methyl methacrylate, and 113 g of tertiary decyl mercaptan are charged into the system, and the mixture is stirred at 150 rpm for 60 minutes.
The internal temperature is raised from room temperature to 70 ° C. in
The reaction was performed for 0 hours. Thereafter, the mixture was cooled to room temperature, and the solid concentration was 48.7% by weight, pH 7.5, and the average particle diameter was 0.19 μ
Aqueous Dispersion Resin 1 was obtained. Production Example 2 Ion-exchanged water 4 in an autoclave equipped with a 100 L stirrer
6 kg and 157 g of sodium lauryl sulfate were charged and the inside of the system was replaced with nitrogen. Thereafter, the internal temperature was increased to 80 ° C. while stirring at 200 rpm, and (A) 18.81 kg of butadiene, 11.28 kg of styrene, 1.25 kg of acrylic acid, and tertiary decyl mercaptan 28
2 g of the mixture, (B) 31 g of sodium lauryl sulfate,
Aqueous solutions of 188 g of sodium persulfate and 1975 g of ion-exchanged water were prepared, and the mixture (A) was added to the reaction system over 6 hours and the aqueous solution (B) over 6.5 hours.
After completion of the addition, the reaction was further carried out for 1 hour as residual monomer polymerization. Thereafter, the mixture was cooled to room temperature to obtain a rubber latex having a solid content of 38.9% by weight and a pH of 1.9. This rubber latex was adjusted to pH 8 with sodium hydroxide, and subjected to steam stripping and concentration to obtain an aqueous dispersion resin 2 having an average particle size of 0.1 μm and a solid concentration of 50% by weight.
Got. Production Example of Plastic Pigment Emulsion Production Example-3 Ion-exchanged water 354 in a flask with a 10 L condenser
7 g, 452 g of seed particles having an average particle diameter of 0.25 μ and a solid concentration of 40% by weight, and 3.6 g of sodium lauryl sulfate
And the inside of the system was replaced with nitrogen. After that, 200rpm
While stirring, raise the internal temperature to 80 ° C,
(A) A mixed solution of 3544 g of styrene and 72.3 g of acrylic acid, (B) an aqueous solution of 159 g of ion-exchanged water, 3.6 g of sodium lauryl sulfate, and 18.1 g of sodium persulfate were prepared. The aqueous solution (B) was added to the reaction system over 6 hours over 5 hours. After completion of the addition, the mixture was further reacted for 2 hours as residual monomer polymerization. Thereafter, the mixture was cooled to room temperature, and the solid content was 48.7% by weight, pH
An emulsion of 2.1 was obtained. Then, the pH was adjusted to 8 with sodium hydroxide to obtain an aqueous dispersion resin 3 having an average particle size of 0.7 μm and a solid content concentration of 48.3% by weight. Examples 1 and 2 2,2-dibromo-2-nitro-1-
Example 1 was a case where ethanol was added at 50 ppm,
Example 2 was also the case where 4000 ppm was added. Examples 3 and 4 2,2-dibromo-2-nitro-1-
The case where 50 ppm of ethanol was added is referred to as Example 3,
Example 4 was also the case where 4000 ppm was added. Examples 5 and 6 2,2-dibromo-2-nitro-1-
Example 5 in which 50 ppm of ethanol was added,
Example 6 was also the case where 4000 ppm was added. Comparative Examples 1 and 2, 2,2-dibromo-2-nitro-1-
Comparative Example 1 was a case where ethanol was added at 5 ppm, and Comparative Example 2 was a case where ethanol was also added at 6000 ppm. Comparative Examples 3 and 4, 2,2-dibromo-2-nitro-1-
Comparative Example 3 was a case where ethanol was added at 5 ppm, and Comparative Example 4 was a case where ethanol was also added at 6000 ppm. Comparative Examples 5 and 6 2,2-dibromo-2-nitro-1-
Comparative Example 5 was a case where ethanol was added at 5 ppm, and Comparative Example 6 was a case where ethanol was also added at 6000 ppm. A storage stability test was performed for each of the aqueous dispersion resin compositions obtained in the above Examples and Comparative Examples. The test method is shown below. The results are summarized in Table 1. Storage stability test method Each aqueous dispersion resin composition was added to a glass tube having a diameter of 1 cm and a length of 1.5 m until a height of 1.45 m was reached. afterwards,
About 1 g of a sample was taken from the upper part of the glass tube every other month for 6 months, and each sample was dried to obtain a solid content. [Table 1] From Table 1, it can be seen that the aqueous dispersion resin composition of the present invention has excellent storage stability. On the other hand, if the use range of the nitro alcohol is out of the range of the present invention, the effect of storage stability cannot be obtained.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08K 5/32

Claims (1)

(57) [Claim 1] 2,2-dibromo- is contained in an aqueous dispersion resin.
2-nitro-1-ethanol and 2-chloro-2-ni
10 to 5000p of compounds selected from troethanol
An aqueous dispersion resin composition containing pm.