Provided is a polycarbonate-polyorganosiloxane copolymer, which is produced by using a diol monomer (a1) and a polyorganosiloxane (a2) satisfying the following condition, including: a polyorganosiloxane block (A-1) including a specific repeating unit; and a polycarbonate block (A-2) formed of a specific repeating unit: a mixture, which is obtained by bringing the diol monomer (a1), the polyorganosiloxane (a2), a carbonic acid diester, and a basic catalyst present at the same amount ratio as that at a time of production of the polycarbonate-polyorganosiloxane copolymer into contact with each other at from 100° C. to 250° C. for from 0.5 hour to 5 hours, has a haze value of 30 or less measured under conditions of 23° C. and an optical path length of 10 mm in conformity with ISO 14782:1999.

Provided is a polycarbonate-polyorganosiloxane copolymer, which is produced by using a diol monomer (a1) and a polyorganosiloxane (a2) satisfying the following condition, including: a polyorganosiloxane block (A-1) including a specific repeating unit; and a polycarbonate block (A-2) formed of a specific repeating unit: a mixture, which is obtained by bringing the diol monomer (a1), the polyorganosiloxane (a2), a carbonic acid diester, and a basic catalyst present at the same amount ratio as that at a time of production of the polycarbonate-polyorganosiloxane copolymer into contact with each other at from 100° C. to 250° C. for from 0.5 hour to 5 hours, has a haze value of 30 or less measured under conditions of 23° C. and an optical path length of 10 mm in conformity with ISO 14782:1999.

A composition for forming a release coating is disclosed. The composition comprises (A) an organopolysiloxane comprising the reaction product of: (i) a silicone resin having a particular formula; and (ii) a cyclic siloxane; in the presence of a polymerization catalyst. The composition further comprises (B) an organopolysiloxane including an average of at least two silicon-bonded ethylenically unsaturated groups per molecule.

One of the objects of the present invention is to provide a thermally conductive silicone resin composition which has good thermal conductivity, a light weight (namely, a light weight per unit volume), and good reliability in high humidity, and a molded body thereof. The present invention provides a thermally conductive silicone resin composition comprising the following components (A) to (E): (A) an organopolysiloxane having at least two alkenyl groups each bonded to a silicon atom in an amount of 100 parts by mass, (B) an organohydrogen polysiloxane having at least two hydrogen atoms each bonded to a silicon atom in an amount such that a ratio of the number of the hydrogen atom bonded to a silicon atom relative to the number of the alkenyl group in component (A) is 0.1 to 2, (C) a thermally conductive filler in an amount of 2500 to 6000 parts by mass, (D) a catalytic amount of an addition reaction catalyst, and (E) an addition-reaction controlling agent in an amount of 0.01 to 1 part by mass, wherein the thermally conductive filler (C) comprises magnesium oxide having a specific surface area of 0.4 m.sup.2/g or less in an amount of 20 to 50 wt % and aluminum hydroxide in an amount of 10 to 30 wt %, relative to a total weight of component (C).

One of the objects of the present invention is to provide a thermally conductive silicone resin composition which has good thermal conductivity, a light weight (namely, a light weight per unit volume), and good reliability in high humidity, and a molded body thereof. The present invention provides a thermally conductive silicone resin composition comprising the following components (A) to (E): (A) an organopolysiloxane having at least two alkenyl groups each bonded to a silicon atom in an amount of 100 parts by mass, (B) an organohydrogen polysiloxane having at least two hydrogen atoms each bonded to a silicon atom in an amount such that a ratio of the number of the hydrogen atom bonded to a silicon atom relative to the number of the alkenyl group in component (A) is 0.1 to 2, (C) a thermally conductive filler in an amount of 2500 to 6000 parts by mass, (D) a catalytic amount of an addition reaction catalyst, and (E) an addition-reaction controlling agent in an amount of 0.01 to 1 part by mass, wherein the thermally conductive filler (C) comprises magnesium oxide having a specific surface area of 0.4 m.sup.2/g or less in an amount of 20 to 50 wt % and aluminum hydroxide in an amount of 10 to 30 wt %, relative to a total weight of component (C).

A curable composition which comprises (A) an organopolysiloxane represented by formula (1)

##STR00001##

(wherein R.sup.1 represents an alkyl group, R.sup.2 represents an alkyl or aryl group, R.sup.3 represents a hydrogen atom or methyl group, Me represents a methyl group, m is an integer of 1-10, and a and b are integers of 1 or larger, a+b being an integer of 3-120), (B) a photopolymerization initiator, and (C) a hydrosilylation catalyst and which has a surface tension at 23° C. of 23-30 mN/m and a viscosity at 23° C. of 5-80 mPa.Math.s.

A curable composition which comprises (A) an organopolysiloxane represented by formula (1)

##STR00001##

(wherein R.sup.1 represents an alkyl group, R.sup.2 represents an alkyl or aryl group, R.sup.3 represents a hydrogen atom or methyl group, Me represents a methyl group, m is an integer of 1-10, and a and b are integers of 1 or larger, a+b being an integer of 3-120), (B) a photopolymerization initiator, and (C) a hydrosilylation catalyst and which has a surface tension at 23° C. of 23-30 mN/m and a viscosity at 23° C. of 5-80 mPa.Math.s.

The invention relates to a method of additive manufacturing an object using a 3D printing apparatus, in which at least one layer or part of at least one layer is formed by an addition-crosslinking electro-conductive silicone composition comprising : (A) at least one organopolysiloxane compound A comprising, per molecule at least two C.sub.2- C.sub.6 alkenyl radicals bonded to silicon atoms, (B) at least one organohydrogenopolysiloxane compound B comprising, per molecule, at least two hydrogen atoms bonded to an identical or different silicon atom, (C) at least one catalyst C comprising at least one metal from the platinum group or the compound thereof, (D) at least one reinforcing silica filler D, (E) at least one thixotropic agent which is selected from compounds having epoxy group, (poly)ether group, and/or (poly)ester group, organopolysiloxane having an aryl group and mixtures thereof; (F) at least one electro-conductive filler F, which is selected from nickel coated carbon, preferably graphite, graphene or mixtures thereof; (G) optionally at least one crosslinking inhibitor G.

The invention relates to a method of additive manufacturing an object using a 3D printing apparatus, in which at least one layer or part of at least one layer is formed by an addition-crosslinking electro-conductive silicone composition comprising : (A) at least one organopolysiloxane compound A comprising, per molecule at least two C.sub.2- C.sub.6 alkenyl radicals bonded to silicon atoms, (B) at least one organohydrogenopolysiloxane compound B comprising, per molecule, at least two hydrogen atoms bonded to an identical or different silicon atom, (C) at least one catalyst C comprising at least one metal from the platinum group or the compound thereof, (D) at least one reinforcing silica filler D, (E) at least one thixotropic agent which is selected from compounds having epoxy group, (poly)ether group, and/or (poly)ester group, organopolysiloxane having an aryl group and mixtures thereof; (F) at least one electro-conductive filler F, which is selected from nickel coated carbon, preferably graphite, graphene or mixtures thereof; (G) optionally at least one crosslinking inhibitor G.

Silicone polyoxamide and silicone polyoxamide-hydrazide copolymers comprise at least two repeating units of formula (I). In this formula, each R.sup.1 is independently an alkyl, haloalkyl, aralkyl, alkenyl, aryl, or aryl substituted with an alkyl, alkoxy, or halo; each Y is independently an alkylene, aralkylene, or a combination thereof; each G is independently a bond or a divalent residue equal to a diamine of formula R.sup.3HN-G-NHR.sup.3 minus the two —NHR.sup.3 groups; each R.sup.3 is independently hydrogen or alkyl or R.sup.3 taken together with G and with the nitrogen to which they are both attached form a heterocyclic group; each n is independently an integer of 0 to 300; each p is independently an integer of 1 to 25, and the average of p is 1.3 or greater; and each q is independently an integer of 1 to 2, and the average of q is no greater than 1.05.

##STR00001##