Aqueous water and oil repellent composition

The present invention relates to a composition for treatment of textile and carpets for imparting excellent water repellency, oil repellency and soil releasability. The present invention relates to the use of a water and oil-repellent composition which is safe for exposure to humans and animals and presents little environmental impact while providing a durable water and oil repellency to a material to be treated with in a highly simplified method of application.

Hitherto, various treatment methods have been proposed in order to impart water, oil and soil repellency to a textile or to a carpet. For example, a process often referred to as “exhaust process” of treating a textile comprises of lowering the pH of a treatment liquid, applying the treatment liquid to the textile, thermally treating the textile with steam, washing the textile with water, and dehydrating the textile as described in the U.S. Pat. Nos. 5,073,442, 5,520,962, 5,516,337 and 5,851,595 and the International Publication WO 98/50619.

The U.S. Pat. No. 5,073,442 discloses a method of treating a textile, comprising of conducting an “exhaust process” by using a water- and oil-repellent agent comprising a fluorine-containing compound, a formaldehyde condensation product and an acrylic polymer. The U.S. Pat. Nos. 5,520,962 and 5,851,595 disclose a method of treating a carpet, comprising of conducting an “exhaust process” by using a fluorinc-containing compound and a polymeric binder. The U.S. Pat. No. 5,516,337 discloses a method of treating a textile, comprising of conducting an “exhaust process” by using a fluorine-containing water- and oil-repellent agent and a metal compound such as aluminum sulfate. The International Publication WO 98/50619 discloses a method of treating a carpet, comprising of conducting an “exhaust process” by using a fluorine-containing water- and oil-repellent agent and a salt such as a magnesium salt. These methods mainly use the water and oil repellent agents in combination with the stain-blocking agents and can give water repellency and oil repellency when using the “exhaust process.” The U.S. Pat. No. 7,147,669 describes an invention wherein no use of a stain blocking agent is made using an “exhaust process.”

It is obvious from the applications described above that the process of inducing water and oil repellency to fabrics is expensive and tedious. There is therefore a need to develop a simpler, less expensive process. The present invention provides such a method of preparing a treated textile, comprising of steps of simply preparing a treatment liquid comprising a water- and oil-repellent agent and applying the treatment liquid to a textile by soaking the textile in it, wherein the water- and oil-repellent agent comprises at least one fluorine-containing compound selected from the group consisting of a fluorine-containing polymers and a fluorine-containing low molecular weight compound, the water- and oil-repellent agent or the treatment liquid additionally contains a cationic emulsifier and/or its salt.

The present invention also provides a textile prepared by the above-mentioned method, and a water- and oil-repellent agent used in the above-mentioned method. A polymer of polymerizable compound having a perfluoroalkyl or perfluoroalkenyl group and an acrylate or methacrylate group can be used as a water and oil-repellent for a fibrous fabric. In order to obtain the perfluoroalkyl group containing (meth)acrylate copolymer, a polymerization method such as bulk polymerization, solution polymerization dispersion polymerization or an emulsion polymerization is used. Emulsion polymerization is industrially advantageous because the copolymer can be obtained directly in the form of an aqueous emulsion in the presence of a surfactant and co-solvent.

However, the water and oil-repellency of a fibrous fabric treated with usual conventional aqueous dispersions is not satisfactory for various reasons. From economical view points, there is a need to develop a water and oil repellent composition that will be capable of imparting water and oil-repellency when used in small quantities, a water and oil-repellent composition capable of achieving the repellency effects when cured at a low temperature, and a water and oil repellent composition capable of providing a high production yield which is less influenced by processing conditions.

One of the objective of the present invention is to provide an aqueous water and oil-repellent composition which can impart durable water and oil-repellency to fibrous materials and exhibits excellent storage stability.

The present invention provides aqueous water and oil-repellent composition comprising:

• • (A) A perfluoroalkyl or perfluoroalkenyl group compound containing acrylate or (meth)acrylate copolymer groups
  • (B) A surfactant comprising quaternary ammonium compound
  • (C) An aqueous medium