Coated pesticidal agents, processes for their preparation and compositions containing them
AssigneeAmerican Cyanamid Company
InventorFakhruddin Ahmed
Life of this patent
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Abstract
The present invention provides a coated pesticidal agent and processes for its preparation. The present invention also provides a wettable powder pesticidal composition containing the coated pesticidal agent.
Claims24
An aqueous process for the preparation of a coated pesticidal agent which process comprises:
- a) preparing an aqueous mixture of a pH-dependent polymer and optionally a plasticizer;
- b) dissolving the pH-dependent polymer by adjusting the pH of the mixture of step (a) with a base to a pH above the solubilization pH of the pH dependent polymer;
- c) adding a pesticidal agent, an ultraviolet protector, optionally a stilbene compound, optionally a disintegrating agent and optionally a glidant to the solution of step (b), and blending to produce a homogeneous suspension containing dissolved pH-dependent polymer;
- d) drying the homogeneous suspension of step (c);
- and optionally
- e) milling the dried material of step (d),
- wherein said pH dependent polymer is selected from the group consisting of methacrylic acid and methyl methacrylate copolymers, maleic anhydride and styrene copolymers, and mixtures thereof.
A process for the preparation of a coated pesticidal agent which process comprises:
- a) blending a mixture of a pH-dependent polymer, a pesticidal agent, optionally a plasticizer, an ultraviolet protector, optionally a stilbene compound, optionally a disintegrating agent and optionally a glidant in an organic solvent selected from the group consisting of acetone, a C.sub.1 -C.sub.3 alcohol, and mixtures thereof;
- b) drying the homogeneous suspension of step (a);
- and optionally
- c) milling the dried material of step (b),
- wherein said pH dependent polymer is selected from the group consisting of methacrylic acid and methyl methacrylate copolymers, maleic anhydride and styrene copolymers, and mixtures thereof.
A coated pesticidal agent which comprises a pesticidal agent core surrounded by a matrix which comprises about 2 to 25% by weight of a pH-dependent polymer selected from the group consisting of methacrylic acid and methyl methacrylate copolymers, maleic anhydride and styrene copolymers, and mixtures thereof, 0% to about 5% by weight of a plasticizer, about 5 to 45% by weight of an ultraviolet protector, 0% to about 75% by weight of a stilbene compound, 0% to about 10% by weight of a disintegrating agent, and 0% to about 10% by weight of a glidant.
A wettable powder pesticidal composition which comprises about 2% to 25% by weight of a wetting agent;
- about 2 to 40% by weight of a dispersing agent;
- about 10 to 70% by weight of a bulking agent;
- about 1 to 10% by weight of a flow enhancing agent;
- 0% to about 20% by weight of a pH-modifying agent;
- and about 5 to 75% by weight of a coated pesticidal agent which comprises a pesticidal agent core surrounded by a matrix which comprises about 2 to 25% by weight of a pH-dependent polymer, selected from the group consisting of methacrylic acid and methyl methacrylate copolymers, maleic anhydride and styrene copolymers, and mixtures thereof, 0% to about 5% by weight of a plasticizer, about 5 to 45% by weight of an ultraviolet protector, 0% to about 75% by weight of a stilbene compound, 0% to about 10% by weight of a disintegrating agent, and 0% to about 10% by weight of a glidant.
Dependencies are inferred from the claim text.