Hotmelt silicone compositions are provided including: (A) a resinous alkenyl group-containing organopolysiloxane component, in which the silicon atom-bonded organic groups do not include an epoxy group-containing organic group, wherein the resinous alkenyl group-containing organopolysiloxane component includes (A-1) a resinous alkenyl group-containing organopolysiloxane including at least two alkenyl groups per molecule and free from a (Ar.sub.2SiO.sub.2/2) unit, and (A-2) a resinous alkenyl group-containing organopolysiloxane including at least two alkenyl groups per molecule and at least one (Ar.sub.2SiO.sub.2/2) unit; (B) an organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms per molecule; and (C) a curing catalyst.

The resinous alkenyl group-containing organopolysiloxane (A-1) is included in an amount of about 5 mass % or more based on the total mass of all the organopolysiloxane components in the hotmelt silicone composition.

A silicone pressure sensitive adhesive composition contains an alkenyl-functional polydiorganosiloxane gum, a polyorganosilicate resin, a polyorganohydrogensiloxane crosslinker, a migration reducing additive, a hydrosilylation reaction catalyst, a hydrosilylation reaction inhibitor, and a solvent. Methods for preparing the silicone pressure sensitive adhesive composition and using it to form a protective film are provided.

Compositions of curable silicone rubber compounds containing at least one metal siloxane-silanol(-ate) compound, a method for preparing curable silicone rubber compounds containing at least one metal siloxane-silanol(-ate) compound, as well as the use of curable silicone rubber compounds containing at least one metal siloxane-silanol(-ate) compound as a sealant, an adhesive material, a potting compound and/or a coating agent.

A converter element is provided, comprising a first conversion region comprising a first phosphor, a second conversion region comprising a second phosphor, wherein the first phosphor has upon excitation a faster radiation decay lifetime than the second phosphor, wherein at least one of the first and second phosphor is embedded in a matrix material, wherein the matrix material comprises a three-dimensionally crosslinked polysiloxane having an organic content of less than 40 wt %. Further, a method for producing a converter element and a radiation emitting device are provided.

A skin-adhesive item is described that can include a substrate F coated continuously or discontinuously on at least one of the two faces thereof by a pressure-sensitive silicone adhesive Z that has been previously sterilized by means of gamma radiation and demonstrates good tack on the skin even after sterilization.

Described is a process for producing SiOC-bonded polyether siloxanes branched in the siloxane portion from cyclic branched siloxanes of the D/T type, wherein said process comprises in a first step reacting the mixtures of cyclic branched siloxanes of the D/T type with acetic anhydride optionally in admixture with simple siloxane cycles under acid catalysis to afford acetoxy-bearing branched siloxanes, in a second step performing the equilibration of the acetoxy-modified branched siloxane with superacid, preferably with addition of acetic acid and in a third step reacting the superacid-treated acetoxysiloxane with polyetherols optionally in the presence of bases and optionally in the presence of an inert solvent.

A coat-forming composition including (A) to (C) below, and containing 100 to 2000 parts by mass of (C) below relative to 100 parts by mass of (A) below: (A) a mixture of coating film-forming components containing (A-1) and (A-2) below at a mass ratio of (A-1):(A-2)=1:1.1 to 1:4.9, (A-1) a hydrolyzable group-containing silicone oligomer having a kinematic viscosity at 25° C. of 10 mm2s-1 or less, and (A-2) a reactive silicone oil having, at one terminal, a functional group from the group of a mercapto group, an amino group, and a monocarbinol group, provided that the reactive silicone oil having a monocarbinol group at one terminal has a functional group equivalent of 4500 g/mol or less; (B) a hydrolysis catalyst; and (C) an organic solvent. The coat-forming composition can form a coating film having both water sliding ability and durability (water sliding ability after abrasion).

Disclosed is a preparation method for a polysiloxane powder filler. The method comprises: providing polysiloxane which contains at least 60 wt % of T unit, wherein T unit is equal to R.sub.1SiO.sub.3-, R.sub.1 is a hydrogen atom or an independently selected organic group comprising 1-18 carbon atoms; and performing heat treatment on the polysiloxane under inert gas atmosphere or vacuum conditions, wherein the heat treatment temperature is 250 to 750 degrees, such that silicon hydroxyl groups in the polysiloxane are condensed to obtain a polysiloxane powder filler having a true density greater than or equal to 1.33 g/cm.sup.3 and more preferably greater than or equal to 1.34 g/cm.sup.3. The polysiloxane powder filler obtained by the described preparation method has low inductivity, low inductivity loss and low radioactivity; and can be used for semiconductor packaging materials, circuit boards and intermediate semi-finished products thereof, and semi-cured sheets or copper clad laminates of high-frequency high-speed circuit boards.

An organopolysiloxane cured film which can be made thin, has an extremely low number of defects on a surface and inside of the film, and exhibits high dielectric breakdown strength with regard to a load voltage is provided. Also provided are applications thereof and a method of manufacturing. The organopolysiloxane cured film has an average thickness within a range of 1 to 200 μm. In general, the number of surface defects is 0 to 1, and the number of internal defects is 0 to 20, when measuring the number of surface defects using optical means in an arbitrary position on the organopolysiloxane cured film with a unit area of 15 mm×15 mm. The organopolysiloxane cured film may be obtained by a rolling step in a clean room or the like, or may be obtained by curing between separators provided with a release layer.

A bio-electrode composition contains (A) an ionic polymer material, (B) an addition reaction-curable silicone having at least a hydrosilyl group, (C) a platinum-group catalyst, and a solvent. The bio-electrode composition has a water content of 0.2 mass % or less. The solvent includes one or more of an ether solvent, an ester solvent, and a ketone solvent each of which does not contain a hydroxy group, a carboxyl group, a nitrogen atom, or a thiol group. Thus, present invention provides: a bio-electrode composition capable of forming a living body contact layer for a bio-electrode which is excellent in electric conductivity and biocompatibility, light-weight, and manufacturable at low cost, and which does not leave residue on skin after attachment to and peeling from the skin; a bio-electrode including a living body contact layer formed of the bio-electrode composition; and a method for manufacturing the bio-electrode.