Title:  Hydrophilic polymer blends used to prevent cow skin infections

United States Patent:  6,203,812

Assignee:  Hydromer, Inc. (Branchburg, NJ)

Filed:  June 29, 1998

The invention discloses a mammalian teat dip for controlling mastitis, a method for preparing the composition and a method of treatment of mammals. The composition contains a film-forming polymer blend and at least one antimicrobial. The polymer blend contains a solvent-soluble, thermoplastic polyurethane and a hydrophilic poly(N-vinyl lactam). Upon application to mammalian skin, this composition leaves a long-lasting, water-resistant, residual, elastic film which treats and protects mammalian skin from infection.

SUMMARY OF THE INVENTION

The present invention is a new mammalian teat dip composition as well as a method for treating mammalian skin. This film-forming composition exhibits antimicrobial properties against the typical contagious mastitis causing pathogens and barrier properties protecting the animal from environmental mastitis.

This aqueous based composition includes a solution of a water-resistant, film forming, polymer blend and at least one antimicrobial agent. Examples of antimicrobial agents include iodine, chlorhexidene, bronopol and triclosan. Upon application to a substrate, this composition leaves a long-lasting, water-resistant, residual, elastic film which treats and protects mammalian skin from infection.

In one formulation the iodine-containing antimicrobial agent is added as an aqueous solution of polyvinylpyrrolidone-iodine (PVP-I₂). In another formulation the iodine-containing antimicrobial agent is added as an aqueous solution of iodine metal and iodide salts. In yet another formulation the iodine-containing antimicrobial agent is added as an aqueous solution of iodine metal, hydriodic acid, and a surfactant. The surfactant can range widely in its degree of ionization, including no ionization.

The chlorhexidine-containing antimicrobial agent can be added as an aqueous solution of chlorhexidine salts.

The polymer blend, as taught by U.S. Pat. No. 4,642,267 (Hydromer, Inc.), consists essentially of two polymer components. One polymer component is an organic, solvent-soluble, preformed, thermoplastic polyurethane which has no reactive isocyanate groups. The other polymer component is a hydrophilic poly(N-vinyl lactam). This polymer blend is capable of withstanding exposure to water without a significant loss of the hydrophilic poly(N-vinyl lactam).

The polyurethane of the polymer blend can be derived from an aromatic polyisocyanate and a polyether polyol; or from an aliphatic polyisocyanate and a polyether polyol; or from an aromatic polyisocyanate and a polyester polyol; or from an aliphatic polyisocyanate and a polyester polyol.

The poly(N-vinyl lactam) of the polymer blend is a water-soluble polyvinylpyrrolidone homopolymer or a poly(N-vinyl caprolactam) homopolymer.

The polymer blend may contain at least one additional compatible polymer component. The additional polymer component is a homopolymer or copolymer of at least one monomer selected from the group consisting of alpha-olefin, vinyl chloride, vinylidene chloride, hydroxyethylmethacrylate, acrylic acid, methacrylic acid, vinyl acetate, vinyl alcohol, and vinyl ether.

The composition may also contain water-soluble or water-dispersible skin conditioning agents, such as glycerin; glycols; polyols, such as polyethylene glycol; lanolin; aloe vera and vitamins. The composition may also contain colorants, fragrances and insect repellants.

The present invention also provides a method of protecting a mammalian teat from infection. This method includes applying the composition to the mammalian teat and evaporating the solvent portion of the composition to form a protective water resistant film.

The instant composition in addition to protecting the animal from contamination and allowing easy removabilty prior to milking, provides an increased resistance to premature loss. Thus, when an animal is released into the environment, the composition will be resistant to environmental water, remaining on the animal for the period between milkings. Unlike polyvinyl alcohol-based formulations which wear off in about 3 to 4 hours, the instant invention imparts water resistance up to 8 hours. Moreover, when the animal returns to the milking site, the antimicrobial barrier coating can be easily removed in about 5 minutes using an aqueous wash. Milking can continue without delay and after milking is finished, the animal can again be treated with the aqueous material forming a new antimicrobial barrier film.

Claim 1 of 23 Claims

What is claimed is:

1. A mammalian teat dip composition comprising:

(i) a solution of a film forming polymer blend comprising a first polymer component which is an organic, solvent-soluble, preformed, thermoplastic polyurethane having no reactive isocyanate groups and a second polymer component which is a hydrophilic poly(N-vinyl lactam), said blend capable of withstanding exposure to water without significant loss of said hydrophilic poly(N-vinyl lactam) in an amount sufficient to form a water-resistant film upon topical application to mammalian skin; and wherein said blend comprises from about 10 to about 80 weight percent of said first polymer and from about 20 to about 90 weight percent of said second polymer;

(ii) at least one antimicrobial agent sufficient to treat and protect mammalian skin from infection; and

(iii) a buffering agent in an amount to provide said composition with a pH of approximately 5;

wherein said composition is capable of being removed easily from said mammalian skin with a surfactant and water.

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