A water repellent composition includes a polyurethane resin compound, a non-fluorine water repellent compound, a surfactant, and a liquid medium. The polyurethane resin compound includes at least one kind selected from the group consisting of a first polyurethane resin compound, a second polyurethane resin compound, and a third polyurethane resin compound.

A method for making a composite material comprising at least one substrate and a covering layer applied to the substrate comprises the following steps: providing a substrate containing a plurality of functional groups which are selected from a group comprising a carboxyl group (COOH), amino group (NH2), thiol group (RSH), hydroxyl group (OH) or a combination thereof,mixing approximately from 30 to 70% by weight of a first compound with from 70 to 30% by weight of a second compound until obtaining a first homogeneous solution of said first compound and said second compound,wherein said first compound is an epoxidized compound comprising at least 1.5 epoxide groups per molecule,said second compound comprises a polyfunctional compound, preferably a bifunctional or trifunctional compound, preferably selected from a group comprising bifunctional carboxylic acids, trifunctional carboxylic acids, a plurality of carboxylic acids having at least 2 or 3 carboxyl groups, dimer carboxylic acids, trimer carboxylic acids, polyfunctional amines, diamines, triamines or admixtures thereof, applying said first solution to said substrate, subjecting said substrate to for a time period of at least approximately 30 minutes a drying step in order to dry said substrate which is provided with said first solution; subjecting said substrate to a cross-linking step in order to cross-link the substrate by maintaining said substrate at a temperature between approximately 50 C. and approximately 90 C., preferably between approximately 75 C. and approximately 80 C., for such a cross-linking time as to cause an opening reaction of at least a portion of the epoxide groups of said first compound in order to form a bond between said first compound with said second compound and said substrate in the region of at least some of the functional groups of said second compound and said substrate and a bond between said first compound and said substrate in the region of at least some of the functional groups of said substrate.

A fluoropolyether group-containing silane compound represented by the following formula (I) wherein the symbols are as defined herein: ##STR00001##

A fluorine-free transparent superhydrophobic coating, and a preparation method therefor and an application thereof are provided. In the preparation method, a three-dimensional network structure formed by self-assembly of a bisamide derivative (1,4-bis[(3,4-dioctyloxyphenyl)-bisamido]benzene, BPH-8) is used as a template; tetraethyl orthosilicate (TEOS) as a silica precursor is adsorbed on a surface of the template to undergo sol-gel polymerization to form silica with high transparency; then BPH-8 is removed by calcination to obtain a fibrous transparent silica surface; the silica surface is hydrophobically modified with octyltrichlorosilane to obtain a transparent superhydrophobic coating. The fluorine-free transparent superhydrophobic coating features a water contact angle of 162.7, a sliding angle of less than 3, and an average transmittance of visible light of 84.8%, and has good self-cleaning ability, and potential application value in the fields of architectural glass, automotive window glass, rearview mirrors, optical lenses, and solar photovoltaics.

Provided is a polyurethane resin composition containing a polyurethane resin (U) and an organic solvent (S), in which the polyurethane resin (U) contains a structural unit derived from a polyoxyethylene diol (A), a structural unit derived from a polycarbonate diol (B), a structural unit derived from an aliphatic isocyanate compound (C), a structural unit derived from a diol (D) having 2 to 6 carbon atoms, and a structural unit derived from a diamine (E) having 2 to 20 carbon atoms.

An ink-repellent member, an ink jet head, and a liquid ejection apparatus that are each excellent in performance. The ink-repellent member includes an underlying portion that contains a metal oxide and has a fluorine compound bonded to a surface thereof. A covalent bond index of a metal element and oxygen of the metal oxide is 0.44 or less, and a ratio of an atom amount of the metal element with respect to a total of a carbon atom amount, an oxygen atom amount, a fluorine atom amount, a silicon atom amount, and the atom amount of the metal element is 1 atm % or less in measurement by X-ray photoelectron spectroscopy on the surface of the underlying portion after the ink-repellent member is subjected to an immersion treatment.