Patent ID: 8754130

Claim:
A biocidal composition comprising: 2,2-dibromomalonamide and an isothiazolinone-based biocide of the formula I: wherein R and R 1 are independently hydrogen, halogen or C 1 -C 4 alkyl, or R and R 1 together with the carbons to which they are attached from a C 4 -C 7 cycloalkyl ring or an aryl group; and Y is H, C 1 -C 12 alkyl, C 3 -C 7 cycloalkyl, aryl or aralkyl wherein the isothiazolinone-based biocide of formula I comprises: 5-chloro-2-methyl-4-isothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the 5-chloro-2-methyl-4-isothiazolin-3-one is from 32:1 to 1:2; 2-methyl-4-isothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the 2-methyl-4-isothiazolin-3-one is from 4:1 to 1:4; 4,5-dichloro-2-n-octylisothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the 4,5-dichloro-2-n-octylisothiazolin-3-one is from 4:1 to 1:16; 1,2-benzisothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the 1,2-benzisothiazolin-3-one is from 1:1 to 1:5; 2-n-octyl-4-isothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the 2-n-octyl-4-isothiazolin-3-one is from 1:2 to 1:320; N-methyl-1,2-benzisothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the N-methyl-1,2-benzisothiazolin-3-one is from 1:1 to 1:256; or N-butyl-1,2-benzisothiazolin-3-one and the weight ratio of 2,2-dibromomalonamide to the N-butyl-1,2-benzisothiazolin-3-one is from 1:2 to 1:8.