TRANSPARENT LIQUID SILICONE RUBBER COMPOSITION

• Main Authors: MURAMATSU Hironobu, SHUDO Shigeki
• Format: Patent
• Language: English; French; German
• Published: 03.04.2024
• Subjects: ADHESIVES; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; CORRECTING FLUIDS; DYES; FILLING PASTES; INKS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; PHYSICS; POLISHES; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF MATERIALS THEREFOR; WOODSTAINS

The present invention provides a transparent liquid silicone rubber composition that does not contain an inorganic filler and includes the following as main components: (A) a silicone resin having, as essential structural units, an RSiOunit (M unit) and a SiOunit (Q unit) (R is a monovalent hydrocarbon group containing 1-6 carbon atoms, and at least 2 R's in a molecule are alkenyl groups); (B) a straight-chain or branched organopolysiloxane containing, in a molecule, 2 or more alkenyl groups bonded to silicon atoms; (C) an organohydrogenpolysiloxane containing, in a molecule, 2 or more hydrogen atoms bonded to silicon atoms; (D) an organopolysiloxane which is liquid at room temperature, having a weight-average molecular weight of 37,000 or less and containing, in a molecule, one or more hydroxyl groups bonded to silicon atoms; and (E) a hydrosilylation reaction catalyst. The present invention is a highly transparent, hydrosilylation-curable liquid silicone rubber composition, wherein the hardness and high transparency are sufficiently retained and the mold releasability is excellent.