Antimicrobial oxazolidine/iodopropynyl-butyl carbamate composition containing less than 0.1wt% free formaldehyde

1. A broad spectrum, synergistic biocidal composition comprising a mixture of a biocidal cyclic hydroxymethyl oxazolidine having the formula

containing less than 0.1 wt. % free formaldehyde and between about 0.1 and about 10 wt. % of iodopropynyl butylcarbamate in an aqueous solution of a polyhydroxide of a C 3 to C 6 aliphatic hydrocarbon, a phenoxyethanol or a mixture thereof.

2. The composition of claim 1 wherein the composition contains between 0.1 and 5 wt. % of iodopropynyl butylcarbamate.

3. The composition of claim 1 wherein the weight ratio of hydroxymethyl oxazolidine to iodopropynyl butyl carbamate is between about 10:1 and about 100:1.

4. A personal care formulation containing a biocidal amount between 0.05 and 1.0 wt. % of the composition of claim 1 .

5. The personal care formulation of claim 4 selected from the group consisting of a hair spray, hair dye, skin lotion and hair conditioner.

6. An industrial formulation selected from the group of a paint, adhesive, ink, pigment dispersion or slurry, paper pulp mixture, latex emulsion, metalworking fluid, caulk and sealant containing between about 0.05–1.0 wt. % of the composition of claim 1 .

7. A broad spectrum, synergistic biocidal composition comprising a mixture of a biocidal cyclic hydroxymethyl oxazolidine having the formula

containing less than 0.1 wt. % free formaldehyde and between 0.1 and about 10 wt. % of iodopropynyl butylcarbamate in an aqueous solution of a compound selected from the group consisting of a C 3 to C 6 diol, phenoxyethanol optionally alkoxylated with a C 2 to C 3 alkoxyl group, polyethylene glycol and mixtures thereof.

8. The composition of claim 7 wherein said solution is an aqueous solution of butanediol, phenoxyethanol or a mixture thereof.

9. A personal care formulation containing 0.05 to 1.0 wt. % biocidal amount of the composition of claim 7 .

10. A process which comprises:

(a) forming a uniform slurry of paraformaldehyde in a liquid selected from the group consisting of an aqueous solution of a polyhydroxide of a C 3 to C 6 hydrocarbon, phenoxyethanol, ethoxylated or propoxylated phenoxyethanol, polyethylene glycol, polypropylene glycol or a mixture thereof;

(b) heating the slurry to a temperature of from about 35 to about 60° C.;

(c) introducing a 0.75 to 5 molar excess of tris(hydroxymethyl)-aminomethane into said slurry;

(d) agitating the mixture of (c) while constantly maintaining said excess of tris(hydoroxymethyl)aminomethane until completion of the reaction indicated by the formation of the substantially pure cyclic hydroxymethyl oxazolidine in a clear solution;

(e) adding between about 0.1 and about 10 wt. % of iodopropynyl butylcarbamate, based on said oxazolidine, to the product of step (d);

(f) constantly agitating the contents of (e) until a second clear solution is formed and

recovering the solution of (f) as a solution of composition containing less than 0.1 wt. % free formaldehyde, iodopropynyl butylcarbamate and cyclic hydroxymethyl oxazolidione having the formula

11. The process of claim 10 wherein said aqueous solution in step (a) is butanediol or phenoxyethanol or a mixture thereof.