Release paper base paper, includes: a substrate; and a coating agent containing a polyvinyl alcohol (A) and a compound (B), the substrate coated with the coating agent, wherein the compound (B) is unsaturated carboxylic acid or a derivative thereof having a pKa of less than 4.00, and 0.1 part by mass or more and 20 parts by mass or less of the compound (B) is contained based on 100 parts by mass of the polyvinyl alcohol (A). The release paper base paper of the present invention is excellent in sealing properties for silicone and waterproofness. The release paper base paper of the present invention is also capable of accelerating curing of silicone in a release layer.

The invention relates to a method for manufacturing thermoplastic poly(vinyl alcohol) derivative in a melt state reaction and a product thereof, wherein the method thermoplastic poly(vinyl alcohol) that has been dried is heated and admixed with an organic acid anhydride that has a catenated carbon structure which ends into a vinyl group, such that a mixture is obtained which is above the melting point of the mixture, thereby causing an ester bond forming condensation reaction in a melt state, wherein at least some of the organic acid anhydride reacts with hydroxyl groups of the thermoplastic poly(vinyl alcohol), such that reaction product is formed which contains carboxylic acid residue and thermoplastic poly(vinyl alcohol) derivative which contains ester bonded pendant chains of which at least some end into vinyl groups. The invention further relates to a method for manufacturing a paper substrate and a product thereof, which contains a primer layer that contains the reaction product.

The invention relates to a method for manufacturing thermoplastic poly(vinyl alcohol) derivative in a melt state reaction and a product thereof, wherein the method thermoplastic poly(vinyl alcohol) that has been dried is heated and admixed with an organic acid anhydride that has a catenated carbon structure which ends into a vinyl group, such that a mixture is obtained which is above the melting point of the mixture, thereby causing an ester bond forming condensation reaction in a melt state, wherein at least some of the organic acid anhydride reacts with hydroxyl groups of the thermoplastic poly(vinyl alcohol), such that reaction product is formed which contains carboxylic acid residue and thermoplastic poly(vinyl alcohol) derivative which contains ester bonded pendant chains of which at least some end into vinyl groups. The invention further relates to a method for manufacturing a paper substrate and a product thereof, which contains a primer layer that contains the reaction product.

One of the purposes of the present invention is to provide an addition-curable organopolysiloxane composition which cures sufficiently with a minor amount of platinum group metal catalyst to exert satisfactory adhesion and provides a cured film having a release force comparable to the prior art cured film, and to provide an addition-curable organopolysiloxane composition which allows the sufficient progress of addition cure even on a substrate comprising a catalyst poison component so as to be suitable for providing a release coating for silicone rubber and release paper or release film. That is, the present invention provides an addition-curable organopolysiloxane composition comprising components (A) to (C): (A) an organopolysiloxane having two or more alkenyl groups each bonded to a silicon atom per molecule and having 0.01 to 2.9, as an average, (meth)acrylic groups, (B) an organohydrogenpolysiloxane having two or more hydrogen atoms each bonded to a silicon atom per molecule in such an amount that a ratio of the number of Si—H groups in component (B) to the number of alkenyl groups in component (A) is 1 to 5, and (C) a platinum group metal catalyst in an amount that a platinum group metal amount is 1 to 100 ppm by mass based on a total mass of the composition.

One of the purposes of the present invention is to provide an addition-curable organopolysiloxane composition which cures sufficiently with a minor amount of platinum group metal catalyst to exert satisfactory adhesion and provides a cured film having a release force comparable to the prior art cured film, and to provide an addition-curable organopolysiloxane composition which allows the sufficient progress of addition cure even on a substrate comprising a catalyst poison component so as to be suitable for providing a release coating for silicone rubber and release paper or release film. That is, the present invention provides an addition-curable organopolysiloxane composition comprising components (A) to (C): (A) an organopolysiloxane having two or more alkenyl groups each bonded to a silicon atom per molecule and having 0.01 to 2.9, as an average, (meth)acrylic groups, (B) an organohydrogenpolysiloxane having two or more hydrogen atoms each bonded to a silicon atom per molecule in such an amount that a ratio of the number of Si—H groups in component (B) to the number of alkenyl groups in component (A) is 1 to 5, and (C) a platinum group metal catalyst in an amount that a platinum group metal amount is 1 to 100 ppm by mass based on a total mass of the composition.

The invention relates to a method for manufacturing a paper substrate suitable for binding silicone in a catalytic hydrosilation reaction and products thereof, wherein the molecular weight of polyvinyl alcohol is used to control the viscosity of the water-based acetalization reaction, such that a paper substrate may be coated with acetalized polyvinyl alcohol that contains high amount of functional vinyl groups, wherein the functional vinyl groups are part of catenated carbon structures which contain at least 4 carbon atoms and which have an acetal connectivity with the backbone chain of the acetalized polyvinyl alcohol.

The invention relates to a method for manufacturing a paper substrate suitable for binding silicone in a catalytic hydrosilation reaction and products thereof, wherein the molecular weight of polyvinyl alcohol is used to control the viscosity of the water-based acetalization reaction, such that a paper substrate may be coated with acetalized polyvinyl alcohol that contains high amount of functional vinyl groups, wherein the functional vinyl groups are part of catenated carbon structures which contain at least 4 carbon atoms and which have an acetal connectivity with the backbone chain of the acetalized polyvinyl alcohol.

The present invention concerns a packaging material having a coating made of a biopolymer composition. In addition, the invention concerns a method for providing barrier properties for a packaging material by using the above mention composition. In particular, the present invention concerns coating of a porous material with a composition comprising a biopolymer formed by the reaction product of biodegradable polyester and siloxane precursor.

The present invention concerns a packaging material having a coating made of a biopolymer composition. In addition, the invention concerns a method for providing barrier properties for a packaging material by using the above mention composition. In particular, the present invention concerns coating of a porous material with a composition comprising a biopolymer formed by the reaction product of biodegradable polyester and siloxane precursor.

Disclosed is a manufacturing process of intermittent coating release paper, which includes: a) undercoating; b) primary drying in a drying oven; c) printing optical marks; d) coating silicon in a section; e) accurately coating heat-sealing material on front and back sides of the base material; f) secondary drying, rolling up, the action of coating the silicon and coating the heat sealing material is precisely positioned by using the optical marks printed in the previous process. The manufactured release paper can be directly applied to the packaging of women's sanitary napkins, pads, and maternity napkins, there is no need to use spaced release paper, the whole can be degraded or recycled for pulping, and can also reduce the use of various coating materials during production, reduce production costs, thus being beneficial to improve the production level of the existing process and the ecological environment protection.