| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition which releases its agrochemical active component of any concentration for a desired period in a sustained manner, and does not remain in soil after it is used because its resin component is decomposed by combining its agrochemical active component with a specific aliphatic polyester to formulate the composition. SOLUTION: This composition is composed of (A) an aliphatic polyester containing at least 90 mol.% of a structural unit shown by the formula [R is H or a 1-3C alkyl; and (n) is 0 to 4], and preferably containing a polyvalent metal (e.g. magnesium) in the main chain at a concentration of 10 to 300 eq/106 g, e.g. polylactic acid, and (B) an agrochemical active component, e.g. pyrazosulfuron-ethyl. It is preferable that the component A contains the lactic acid residue at 60 mol% or more, and has an L-lactic acid/D-lactic acid molar ratio of 1 to 9 and acid value of 1 to 1000 eq/106 g. It is also preferable that the component B is coated with the component A.
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