Stabilization of 5-chloro-3-isothiazolones

Claim 2

A stable non-aqueous solution of one or more isothiazolones of the formula: wherein Y is an unsubstituted or substituted alkyl of 1 to 8 carbon atoms, an unsubstituted or halo substituted alkenyl or alkynyl group of 2 to 8 carbon atoms, an unsubstituted or substituted cycloalkyl of 5 to 8 carbon atoms, an unsubstituted or substituted aralkyl, or an unsubstituted or substituted aryl; R is hydrogen, halo, or a (C 1 to C 4 )alkyl; wherein the solution contains from 89 to 99.5% by weight of one or more hydroxy solvent of the formulae: or or wherein R and R 1 are hydrogen or lower alkyl, X is -CH 2 OCH 2 - or -(CH 2 ) n̅ wherein n is an integer of 1 to 4 and y is an integer of 1 to 150, and 0 to 1% by weight of stabilization salt; the percentages being by weight of the three stated components.

Claim 3

A solution as claimed in claim 1 wherein the isothiazolone content is from 3 to 10% by weight and the solvent content is from 89 to 97% by weight.

Claim 4

A solution as claimed in claim 1 or 2 wherein the isothiazolone content is from 6 to 10% by weight, the hydroxy solvent content is from 89 to 93.7% by weight and the stabilization salt content is from 0.3 to 1% by weight.

Claim 5

A solution as claimed in any preceding claim wherein the solvent comprises propylene glycol, polypropylene glycol, 1,5-pentandiol, benzyl alcohol or, preferably, dipropylene glycol.

Claim 6

A solution as claimed in any preceding claim wherein the isothiazolone comprises 5-chloro-2-methyl-4-isothiazolin-3-one.

Claim 7

A solution as claimed in any preceding claim wherein the stabilization salt comprises metal nitrate or copper (2+) salt.

Claim 8

A solution as claimed in any preceding claim wherein the stabilization salt comprises copper nitrate.

Claim 9

A process for producing a stable non-aqueous solution of one or more isothiazolones of the formula: wherein Y is an unsubstituted or substituted alkyl of 1 to 8 carbon atoms, an unsubstituted or halo substituted alkenyl or alkynyl of 2 to 8 carbon atoms, an unsubstituted or substituted cycloalkyl of 5 to 8 carbon atoms, an unsubstituted or substituted aralkyl or an unsubstituted or substituted aryl; R is hydrogen, halo, or a (C 1to C4)alkyl; which comprises formulating the solution to contain 0.5 to 10% by weight isothiazolone, 8 to 99% by weight of one or more hydroxy solvents of the formulae: or or wherein R and R 1 are hydrogen or lower alkyl, X is -CH 2 OCH 2 - or -(CH 2 ) n̅ wherein n is an integer of 1 to 4 and y is an integer of I to 150; and 0 to 1% by weight of one or more stabilization salts; the percentages being by weight of the three stated components.

Claim 10

A process for producing a stable non-aqueous solution of one or more isothiazolones of the formula: wherein Y is an unsubstituted or substituted alkyl of 1 to 8 carbon atoms, an unsubstituted or halo substituted alkenyl or alkynyl of 2 to 8 carbon atoms, an unsubstituted or substituted cycloalkyl of 5 to 8 carbon atoms, an unsubstituted or substituted aralkyl or an unsubstituted or substituted aryl; R is hydrogen, halo, or a (C 1to C4)alkyl; which comprises formulating the solution to contain 0.5 to 10% by weight isothiazolone, 8 to 99% by weight of one or more hydroxy solvents of the formulae: or or wherein R and R 1 are hydrogen or lower alkyl, X is -CH 2 OCH 2 - or -(CH 2 ) n̅ wherein n is an integer of 1 to 4 and y is an integer of I to 150; and 0 to 1% by weight of one or more stabilization salts; the percentages being by weight of the three stated components.

Claim 11

A process as claimed in claim 8 as applied to the production of a solution as claimed in any of claims 2 to 7.

Claim 12

The use of a solution as claimed in any of claims 1 to 7 as a biocide or preservative.