Provided is a surface treatment agent which does not use fluorine-containing monomers, particularly fluoroalkyl group-containing monomers. The surface treatment agent is a water-based emulsion which includes: a copolymer (1) which includes a first polymer formed from first monomers, and a second polymer formed from second monomers, wherein the second polymer is polymerized in the presence of the first polymer, the first monomers include a long-chain acrylate ester monomer (a) represented by the formula CH.sub.2═CA.sup.11—C(═O)—O-A.sup.12 (in the formula, A.sup.11 represents hydrogen, a monovalent organic group, or a halogen, and A.sup.12 represents a C.sub.18-30 straight-chain or branched hydrocarbon group), the first monomers do not include a halogenated olefin monomer (b), and the second monomers include the halogenated olefin monomer (b); a surfactant (2) including a nonionic surfactant; and a liquid medium (3) including water.

A water-repellent knitted fabric is a knitted fabric which comprises a multifilament made of a thermoplastic resin and has a water repellent imparted to a surface of the knitted fabric or the multifilament, and satisfies the following conditions (1) to (4): (1) the number of voids between stitches of the knitted fabric is 20 to 40/[12 cm×12 cm], and the voids have a size of 7 to 25 mm.sup.2; (2) initial water repellency measured in accordance with a spray method described in JIS L-1092 is at a grade 3 or higher; (3) initial Water drainage is 70% or more; and (4) initial Bursting Strength measured in accordance with a method A described in JIS L-1096 is 200 kPa or more and 500 kPa or less.

The present disclosure relates to methods for producing water repellent textile substrates and products thereof. The methods can be conducted without the use of perfluorocarbons.

In one aspect, a composition for treating fibers comprises an acidic aqueous or aqueous-based continuous phase and a liquid repellent phase comprising a dendrimer component and/or non-dendrimer alkyl urethane. The treatment composition, for example, can have pH of 2.5 to 6.5. In some embodiments, carboxylic acid is employed in the treatment composition for providing the acidic character of the aqueous or aqueous-based continuous phase. Moreover, the treatment composition can further comprise at least one of an acid stain resist component and soil release component. In some embodiments, fibers treated with compositions described herein exhibit ionic character.

A liquid repellent cloth or liquid repellent film according to an embodiment includes abase fabric selected from a fiber cloth or a synthetic resin film, and a liquid repellent membrane supported on at least one principal face of the base fabric. The liquid repellent membrane is a monomolecular membrane of a fluorine-containing organic compound that binds to a surface of the base fabric through a binding moiety represented by —Z—O—* (wherein Z represents an atomic group containing a Si atom, and * represents a binding site to the surface of the base fabric) and includes a perfluoroalkyl group having 4 or less carbon atoms at a terminal, and the fluorine-containing organic compound undergoes intermolecular bonding between the fluorine-containing organic compounds adjacent to each other by mutual binding of Z in the formula.

Prepregs, cores and composite articles are described that comprise lighter weight materials and/or lower amounts of adhesive than commonly used. In some instances, one or more components of the articles may comprise a repellent material or repellent treatment to reduce the overall absorption rate of adhesive into the components of the article.

A treated textile material comprises a textile substrate and a finish on the yarns making up the textile substrate. The yarns of the textile substrate comprise inherent flame resistant fibers. The finish comprises a fluorochemical repellent. The treated textile material exhibits improved resistance to chemical splashes and spills, such as those encountered in institutional and commercial laboratory settings.

A water-repellent knitted fabric is a knitted fabric which comprises a multifilament made of a thermoplastic resin and has a water repellent imparted to a surface of the knitted fabric or the multifilament, and satisfies the following conditions (1) to (4): (1) the number of voids between stitches of the knitted fabric is 20 to 40/[12 cm×12 cm], and the voids have a size of 7 to 25 mm.sup.2; (2) initial water repellency measured in accordance with a spray method described in JIS L-1092 is at a grade 3 or higher; (3) initial Water drainage is 70% or more; and (4) initial Bursting Strength measured in accordance with a method A described in JIS L-1096 is 200 kPa or more and 500 kPa or less.

The present invention relates to improved bentonite barrier compositions, and more particularly, to the use of geosynthetic clay liners including these improved bentonite barrier compositions having enhanced low permeability over time in containment applications. A geosynthetic clay liner comprises at least one geosynthetic layer; and a bentonite barrier composition comprising bentonite and a polyanionic starch, wherein the polyanionic starch is carboxymethyl starch.

A non-fluorinated block copolymer including at least one block segment (A), wherein the block segment (A) includes a repeating unit formed from one or more types of acrylic monomers having a long-chain hydrocarbon group containing 7-40 carbon atoms. The non-fluorinated block copolymer preferably contains a segment (B) constituted by at least one of: (B1) a block segment including a repeating unit, different from that of segment (A), that is formed from an acrylic monomer having a long-chain hydrocarbon group comprising 7-40 carbon atoms; (B2) a block segment including a repeating unit formed from an acrylic monomer not having a long-chain hydrocarbon group; and (B3) a random segment formed from at least two types of acrylic monomers.