US 12,239,130 B2
Encapsulation of herbicides to reduce crop injury
William Abraham, Wildwood, MO (US); David Z. Becher, St. Louis, MO (US); Brett H. Bussler, Webster Groves, MO (US); Amanda C. Herr, St. Louis, MO (US); and S. Douglas Prosch, Ballwin, MO (US)
Assigned to MONSANTO TECHNOLOGY LLC, St. Louis, MO (US)
Filed by Monsanto Technology LLC, St. Louis, MO (US)
Filed on Oct. 12, 2020, as Appl. No. 17/067,977.
Application 17/067,977 is a continuation of application No. 15/860,733, filed on Jan. 3, 2018, granted, now 10,813,352.
Application 15/860,733 is a continuation of application No. 12/705,789, filed on Feb. 15, 2010, granted, now 9,877,478, issued on Jan. 30, 2018.
Claims priority of provisional application 61/152,533, filed on Feb. 13, 2009.
Prior Publication US 2021/0137109 A1, May 13, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. A01N 37/26 (2006.01)
CPC A01N 37/26 (2013.01) 27 Claims
 
1. An herbicidal composition comprising:
microcapsules dispersed in an aqueous liquid, the microcapsules comprising a shell wall comprising a polyurea and containing a water-immiscible core material comprising an acetamide herbicide, wherein the acetamide herbicide comprises acetochlor,
wherein the shell wall is formed in a polymerization medium by a polymerization reaction between a polyisocyanate component comprising a mixture of aliphatic polyisocyanates and a polyamine component comprising a polyamine or mixture of polyamines to form the polyurea and
wherein the microcapsules have a mean particle size range of from about 9 μm to about 12 μm, the composition further comprising:
a thickener selected from the group consisting of guar- or xanthan-based gums, cellulose ethers, modified cellulosics and polymers, and microcrystalline cellulose anti-packing agents; and
urea; and wherein:
the core material further comprises from about 1% to about 10% by weight of a water-insoluble paraffinic hydrocarbon organic solvent selected from linear or branched hydrocarbons;
the mixture of aliphatic polyisocyanates comprises:
a cycloaliphatic diisocyanate of structure (IX):

OG Complex Work Unit Chemistry
 and
an aliphatic triisocyanate of structure (X):

OG Complex Work Unit Chemistry
 and
the polyamine or the mixture of polyamines comprises triethylene tetramine.