Dispersing agent for agrochemicals and fluid dispersion using the same
View Patent ↗Disclosed is a dispersing agent for agrochemicals, said dispersing agent which comprises a modified polyvinyl alcohol-based resin containing a structural unit having a nonionic hydrophilicity group in side chain, and having a saponification degree of 95 mol % or more. The dispersing agent for agrochemicals can provide a dispersion in which a hardly water-soluble agrochemical active ingredient employed for a dispersoid is dispersed in a stable state even in the case where the dispersoid has a relatively large particle size.
1. An agrochemical fluid dispersion consisting of
a hardly water-soluble agrochemical active ingredient optionally dissolved in an organic solvent;
water as a dispersion medium; and
a modified-polyvinyl alcohol-based resin,
said modified-polyvinyl alcohol-based resin having 95 mol % or more saponification degree and containing a structural unit represented by the formula (1) which has a nonionic hydrophilic group in side chain;
and
wherein the modified-polyvinyl alcohol-based resin emulsifies the hardly water-soluble agrochemical active ingredient, and
wherein Z is nonionic hydrophilic group, R 1 , R 2 , and R 3 each is independently a hydrogen or an alkyl group having 1 to 5 carbon atoms and optionally having a substituent, and X is single bond or a binding chain.
2. The agrochemical fluid dispersion according to claim 1 , wherein the agrochemical active ingredient is liquid.
3. The agrochemical fluid dispersion according to claim 1 , wherein the agrochemical active ingredient is solid at room temperature but exists in a form of a solution in which the agrochemical active ingredient is dissolved in the organic solvent.
4. The agrochemical fluid dispersion according to claim 1 , wherein the average particle diameter of the dispersoid is in the range of 10 to 70 μm.
5. The agrochemical fluid dispersion according to claim 1 , wherein the nonionic hydrophilic group is a hydroxyl-containing group.
6. The agrochemical fluid dispersion according to claim 1 , wherein the hydroxyl-containing group contains one or two primary and/or secondary hydroxyl group(s).
7. The agrochemical fluid dispersion according to claim 1 , wherein the structural unit represented by the formula (1) has 8 to 10 in HLB value determined by Davies' method.
8. The agrochemical fluid dispersion according to claim 1 , wherein the modified-polyvinyl alcohol is a polyvinyl alcohol-based resin where the structural unit represented by the formula (1) is a unit represented by the formula (2) having 1,2-diol in side chain,
wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 each is independently hydrogen or an alkyl group having from 1 to 5 carbon atoms and optionally having a substituent, and X is single bond or a binding chain.
9. The agrochemical fluid dispersion according to claim 1 , wherein the modified-polyvinyl alcohol is a polyvinyl alcohol-based resin where the structural unit represented by the formula (1) is a unit represented by the formula (3) having oxyalkylene,
wherein R 1 , R 2 , R 3 , R 7 , R 8 , R 9 , and R 10 each is independently is hydrogen or an alkyl group having from 1 to 5 carbon atoms and optionally having a substituent, X is single bond or a binding chain, and n is integer of 5 to 50.
10. The agrochemical fluid dispersion according to claim 1 , wherein the modified polyvinyl alcohol-based resin has a polymerization degree of 100 to 4000.
11. The agrochemical fluid dispersion according to claim 1 , wherein the content of the structural unit of the formula (1) in the modified polyvinyl alcohol-based resin is in the range of 0.1 to 15 mol %.
12. A method of dispersing a hardly water-soluble agrochemical active ingredient in water consisting of
dispersing the hardly water-soluble agrochemical active ingredient in water in the presence of a modified-polyvinyl alcohol-based resin which has 95 mol % or more saponification degree and contains a structural unit represented by the formula (1) which has a nonionic hydrophilic group in side chain,
wherein Z is nonionic hydrophilic group, R 1 , R 2 , and R 3 each is independently a hydrogen or an alkyl group having 1 to 5 carbon atoms and optionally having a substituent, and X is single bond or a binding chain,
and wherein the hardly water-soluble agrochemical active ingredient is liquid.
13. The method of dispersing a hardly water-soluble agrochemical active ingredient in water according to claim 12 , wherein the modified-polyvinyl alcohol is a polyvinyl alcohol-based resin where the structural unit represented by the formula (1) is a unit represented by the formula (2) having 1,2-diol in side chain,
wherein R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 each is independently hydrogen or an alkyl group having from 1 to 5 carbon atoms and optionally having a substituent, and X is single bond or a binding chain.
14. The method of dispersing a hardly water-soluble agrochemical active ingredient in water according to claim 12 , wherein the modified-polyvinyl alcohol is a polyvinyl alcohol-based resin where the structural unit represented by the formula (1) is a unit represented by the formula (3) having oxyalkylene,
wherein R 1 , R 2 , R 3 , R 7 , R 8 , R 9 , and R 10 each is independently is hydrogen or an alkyl group having from 1 to 5 carbon atoms and optionally having a substituent, X is single bond or a binding chain, and n is integer of 5 to 50.