Abstract: A metal material having a photocatalytic activity which comprises an anodized layer and a thin layer containing titanium oxide powder which are heat treated are sequentially laminated on the surface of a substrate comprising metal material including titanium. By anodically oxidizing the metal material including titanium, an anodized layer is formed on the surface thereof. A thin layer containing titanium oxide powder is further coated on this surface, and heat treatment is carried out before and/or after forming this thin layer containing titanium oxide powder.

Abstract: There are here disclosed carbon fibers for reinforcement of cement which are obtained by applying, onto the surfaces of carbon fibers, esters of oleic acid and aliphatic monovalent alcohols, esters of oleyl alcohol and monovalent fatty acids, polyoxyalkylene bisphenol ethers or polyether esters as sizing agents, and a cement composite material having a bending strength of 300 kgf/cm.sup.2 or more which contains cut carbon fibers having a fiber length of 10 to 50 mm at a mixing volume ratio of the cut carbon fibers to the cement matrix in the range of 1 to 5%. According to the present invention, there are provided the carbon fibers for reinforcement of cement which have excellent adhesive properties to the cement, good process passage properties through a direct spray gun and good bundling properties and which are suitable for a direct spray method, and the cement composite material using the carbon fibers and having high bending strength.

Abstract: There are here disclosed carbon fibers for reinforcement of cement which are obtained by applying, onto the surfaces of carbon fibers, esters of oleic acid and aliphatic monovalent alcohols, esters of oleyl alcohol and monovalent fatty acids, polyoxyalkylene bisphenol ethers or polyether esters as sizing agents, and a cement composite material having a bending strength of 300 kgf/cm.sup.2 or more which contains cut carbon fibers having a fiber length of 10 to 50 mm at a mixing volume ratio of the cut carbon fibers to the cement matrix in the range of 1 to 5%. According to the present invention, there are provided the carbon fibers for reinforcement of cement which have excellent adhesive properties to the cement, good process passage properties through a direct spray gun and good bundling properties and which are suitable for a direct spray method, and the cement composite material using the carbon fibers and having high bending strength.

Abstract: Carbon fiber rovings for reinforcement of concrete are here disclosed which are obtained by sizing, with a sizing agent, strands each consisting of 100 to 1,000 monofilaments of mesophase pitch-based carbon fibers, and then bundling the thus sized 5 to 100 strands into one roving.