Polyorganosiloxanes and methods for their preparation are disclosed. The polyorganosiloxanes are useful in curable compositions. The polyorganosiloxanes may have up to 9 silicon bonded hydrogen atoms, or other curable groups, per molecule.

Polyorganosiloxanes and methods for their preparation are disclosed. The polyorganosiloxanes are useful in curable compositions. The polyorganosiloxanes may have up to 9 silicon bonded hydrogen atoms, or other curable groups, per molecule.

A one-part low modulus room temperature vulcamsable (RTV) silicone composition comprising a titanate and/or zirconate catalyst which cures to a low modulus silicone elastomer which has a good adhesion profile and may be used as a non-staining (clean) sealant having high movement capability which compositions contains an aminosilane adhesion promoter having two hydroxyl or hydrolysable groups per molecule in an amount of 0.1-3.75% by weight of the composition.

The present invention relates to a modified siloxane resin, a crosslinked modified siloxane resin, and a method for preparing the crosslinked resin. More specifically, the present invention relates to a modified siloxane resin, a crosslinked modified siloxane resin with excellent superhydrophobicity obtained by dual curing of the resin, and a method for preparing the crosslinked resin. The use of the modified siloxane resin according to the present invention allows the crosslinked modified siloxane resin to have excellent superhydrophobicity and high hardness. The water repellency of the crosslinked resin can be appropriately controlled by varying the amount of the siloxane resin mixed.

The present invention relates to a modified siloxane resin, a crosslinked modified siloxane resin, and a method for preparing the crosslinked resin. More specifically, the present invention relates to a modified siloxane resin, a crosslinked modified siloxane resin with excellent superhydrophobicity obtained by dual curing of the resin, and a method for preparing the crosslinked resin. The use of the modified siloxane resin according to the present invention allows the crosslinked modified siloxane resin to have excellent superhydrophobicity and high hardness. The water repellency of the crosslinked resin can be appropriately controlled by varying the amount of the siloxane resin mixed.

A method for coating a composite substrate characterized includes a—preparing a sol-gel composition by mixing in an aqueous medium: 1—of at least one metal alkoxide of formula (I) M(OR.sup.1), 2—in the presence of at least one organo alkoxysilane of formula (II) R.sup.3mSi(OR.sup.2).sub.4-m, 3—and in the presence of optional oxide or metal particles, 4—by mixing the composition in order to allow condensation of the organic-inorganic hybrid networks, b—depositing at least one underlayer of the sol-gel composition obtained in step a) on the composite substrate; c—depositing at least one subsequent coating layer on the coated composite substrate obtained in step b).

The invention provides a contact lens manufacturing method for cast-molding of silicone hydrogel contact lenses having enhanced oxygen permeability without adversely affecting desirable lens mechanical properties (e.g., modulus). A method of the invention comprises adding a small amount of a radical scavenger (e.g., H-TEMPO) in a polymerizable composition for cast-molding of SiHy contact lenses) to provide the resultant polymerizable composition with a bi-phase curing profile at a curing temperature of from about 45° C. to about 100° C. With such a bi-phase curing profile, the resultant polymerizable composition can be thermally cured at the curing temperature to form a SiHy contact lens having an oxygen permeability higher than that for a polymerizable composition having the substantially identical composition excepting being free of any radical scavenger.

One of the purposes of the present invention is to provide an emulsion composition which is stable over time and gives, upon drying, a coating with good slipping property. Another purpose of the present invention is to provide an emulsion composition containing a reduced or, in particular, zero amount of octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane as impurities. The present invention provides an aqueous dispersion comprising an emulsion comprising a silicone which is a condensation reaction product of the following components (A-1) and (B): (A-1) a linear organopolysiloxane being an addition reaction product of (a1) a linear organopolysiloxane having two alkenylsilyl groups each only at each of molecular terminals and (a2) a linear organopolysiloxane having two hydrosilyl groups each only at each of molecular terminals, provided that a ratio of the number of the hydrosilyl group in component (a2) to the number of the alkenylsilyl group in component (a1) is 0.98 to 2; 5 to 40 parts by mass of (B) a hydrolysable silane having at least three groups selected from the group consisting of a silanol group and an alkoxy group in one molecule, relative to 100 parts by mass of component (A-1); 0.1 to 20 parts by mass of (A-2) a surfactant, relative to 100 parts by mass of component (A-1); and 10 to 200 parts by mass of (A-3) water, relative to 100 parts by mass of component (A-1).

One of the purposes of the present invention is to provide an emulsion composition which is stable over time and gives, upon drying, a coating with good slipping property. Another purpose of the present invention is to provide an emulsion composition containing a reduced or, in particular, zero amount of octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane as impurities. The present invention provides an aqueous dispersion comprising an emulsion comprising a silicone which is a condensation reaction product of the following components (A-1) and (B): (A-1) a linear organopolysiloxane being an addition reaction product of (a1) a linear organopolysiloxane having two alkenylsilyl groups each only at each of molecular terminals and (a2) a linear organopolysiloxane having two hydrosilyl groups each only at each of molecular terminals, provided that a ratio of the number of the hydrosilyl group in component (a2) to the number of the alkenylsilyl group in component (a1) is 0.98 to 2; 5 to 40 parts by mass of (B) a hydrolysable silane having at least three groups selected from the group consisting of a silanol group and an alkoxy group in one molecule, relative to 100 parts by mass of component (A-1); 0.1 to 20 parts by mass of (A-2) a surfactant, relative to 100 parts by mass of component (A-1); and 10 to 200 parts by mass of (A-3) water, relative to 100 parts by mass of component (A-1).

A method for making a ceramic body comprised of a ceramic material having an inhibitory effect on bacterial growth is provided. A dental prosthesis may be made of a ceramic material that comprises a molybdenum-containing component on a portion of the prosthesis that contacts the gingival surface of a patient. In one method, a porous zirconia ceramic structure is shaped in the form of a dental prosthesis, and then infiltrated with a molybdenum-containing composition, before sintering to densify the ceramic structure.