BINARY PROCESS FOR MANUFACTURE OF DIPPED LATEX PRODUCTS

• US 20160145401A1
• Filed: 01/17/2014
• Published: 05/26/2016
• Est. Priority Date: 07/10/2013
• Status: Active Grant

• Current Assignee: TTK Healthcare Limited (T.T. Krishnamachari & Co. Ltd.)
• Original Assignee: TTK Protective Devices Limited (T.T. Krishnamachari & Co. Ltd.)
• Inventors: Potter, William D., Balasubramanian, N., Jagannathan, Srinivasan
• Granted Patent: US 10,214,621 B2
• Time in Patent Office: Days
• CPC Class Codes: C08J 2307/02 Latex
• CPC Class Codes: C08J 2309/10 Latex C08J2309/04, C08J2309/08 take precedence
• CPC Class Codes: C08J 5/02 Direct processing of dispersions, e.g. latex, to articles
• CPC Class Codes: C08L 7/02 Latex

Abstract

A binary process for manufacturing dipped latex product. The binary process disclosed herein eliminates the influence of any level of pre-vulcanization on the outcome of the dipping process whether using natural or synthetic latex. The binary process includes preparing a first latex mixture Formulation A including latex, one or accelerators, and one or more surfactants, and preparing a second latex mixture Formulation B including latex, one or more curing agents, and one or more surfactants. Further, dipping one or more formers into the Formulation A and B separately in order to form a plurality of coatings/layers of the Formulation A and B, and later on curing the plurality of coatings/layers on the formers to form the dipped latex products, which can be a condom, glove, balloon, catheter, finger cot, surgical tubing, baby bottle nipple or dental dam.

Claims

1-12. -12. (canceled)

13. A binary process for manufacturing dipped latex product, the said process comprising:

preparing a first latex mixture Formulation A comprising latex, one or accelerators, and one or more surfactants;

preparing a second latex mixture Formulation B comprising latex, one or more curing agents, and one or more surfactants;

dipping one or more formers into the Formulation A and B separately in order to form a plurality of coatings/layers of the Formulation A and B; and

curing the plurality of coatings/layers on the formers to form the dipped latex products.

14. The binary process as claimed in claim 13, wherein the latex used for preparing the Formulation A is natural latex, synthetic latex or combinations thereof.

15. The binary process as claimed in claim 13, wherein the latex used for preparing the Formulation B is natural latex, synthetic latex or combinations thereof.

16. The binary process as claimed in claim 13, wherein the one or more accelerators are selected from the group consisting zinc di-butyl dithiocarbamate, zinc diethyl dithiocarbamate, sodium dibutyldithiocarbamate, and sodium diethyl dithio carbamate.

17. The binary process as claimed in claim 13, wherein the one or more curing agents are selected from a group consisting sulphur paste, polymeric sulphur, and sulphur donors.

18. The binary process as claimed in claim 13, wherein the one or more surfactants are selected from the group consisting of dodecyl benzene sulphonate, sodium salt of condensed sulfonated naphthalene, sodium salts of sulfated methyl oleate potassium hydroxide solution, and cetyl stearyl alcohol etherified with 20 mol ethylene oxide solution.

19. The binary process as claimed in claim 13, wherein the formation of plurality of layers/coatings comprises dipping of one or more formers initially in the Formulation A to a depth sufficient to yield the finished latex product of desired length to form first layer/coating, drying partially or completely the first layer/coating, then dipping the first layer/coating in the Formulation B to form a second layer/coating, and drying the second layer/coating and then curing.

20. The binary process as claimed in claim 13, wherein the formation of plurality of layers/coatings comprises dipping of one or more formers initially in the Formulation A to a depth sufficient to yield the finished latex product of desired length to form first layer/coating, drying completely the first layer/coating, then dipping the first layer/coating in Formulation B to form a second layer/coating, drying partially or completely the second layer/coating, further dipping the second layer /coating in Formulation A to form a third layer/coating, and drying completely the third layer/coating and then curing.

21. The binary process as claimed in claim 13, wherein the pH of the Formulations A and B is adjusted to a range of about 11.5 to 12.5.

22. The binary process as claimed in claim 13, wherein the temperature of latex is maintained within 27±

3°

C. throughout the process.

23. The binary process as claimed in claim 13, wherein the layers/coatings on the formers are dried in a hot oven maintained within a range of 60°

C. to 120°

C.

24. The binary process as claimed in claim 13, wherein the dipped latex product is a condom, glove, balloon, catheter, finger cot, surgical tubing, baby bottle nipple or dental dam.