This invention relates to aminoplast crosslinker resins compositions based on at least partially alkylated reaction products A of melamine, formaldehyde and an alkanol with the following parameters: the ratio of the amount of substance n(CH.sub.2O) of combined formaldehyde to the amount of substance n(Mel) of melamine is in the range of from 5.6 mol/mol to 6.2 mol/mol, the ratio of the amount of substance n(RO) of alkyl ether groups in the crosslinker resin to the amount of substance n(Mel) of melamine is in the range of from 5.0 mol/mol to 5.6 mol/mol, the mass fraction of monomer in the resin, calculated as the ratio of the mass of monomer m(1) to the mass m(A) of the reaction products A is between 35% and 55%, to a process for their preparation, and to a method of use thereof as crosslinker in combination with hydroxy-functional polymers for coating of heat-sensitive substrates.

This invention relates to aminoplast crosslinker resins compositions based on at least partially alkylated reaction products A of melamine, formaldehyde and an alkanol with the following parameters: the ratio of the amount of substance n(CH.sub.2O) of combined formaldehyde to the amount of substance n(Mel) of melamine is in the range of from 5.6 mol/mol to 6.2 mol/mol, the ratio of the amount of substance n(RO) of alkyl ether groups in the crosslinker resin to the amount of substance n(Mel) of melamine is in the range of from 5.0 mol/mol to 5.6 mol/mol, the mass fraction of monomer in the resin, calculated as the ratio of the mass of monomer m(1) to the mass m(A) of the reaction products A is between 35% and 55%, to a process for their preparation, and to a method of use thereof as crosslinker in combination with hydroxy-functional polymers for coating of heat-sensitive substrates.

Provided are a resin composition that can form a printed wiring board with a low dielectric constant and dielectric loss tangent and excellent alkali resistance and desmear resistance; and a prepreg, a resin sheet, a metal foil-clad laminate, and a printed wiring board formed using this resin composition. The resin composition contains a styrene-based elastomer (A), a styrene oligomer (B), a maleimide compound (C), and a cyanate ester compound (D).

This invention pertains to a curable composition comprising a first component having beta-ketoacetate and/or malonate functionalities and a second component having two or more aldehyde functionalities. The compositions can be cured at room temperature or low temperatures to yield crosslinked networks that are capable of providing desirable properties for coating and adhesive applications. The reactive functionalities of beta-ketoacetate, malonate, and aldehyde can be either on polymers as the main binders or on small molecules as the crosslinkers. The curable compositions desirably are either solventless or organic solvent based.

This invention pertains to a curable composition comprising a first component having beta-ketoacetate and/or malonate functionalities and a second component having two or more aldehyde functionalities. The compositions can be cured at room temperature or low temperatures to yield crosslinked networks that are capable of providing desirable properties for coating and adhesive applications. The reactive functionalities of beta-ketoacetate, malonate, and aldehyde can be either on polymers as the main binders or on small molecules as the crosslinkers. The curable compositions desirably are either solventless or organic solvent based.

In a method in which a workpiece, while being temporarily fixed on a support via a temporary fixing material, is processed and/or transported and thereafter the support and the workpiece are separated from each other by an irradiation separation method, a technique is shown which prevents the photo-degradation of the workpiece. A workpiece treating method includes a step of forming a stack including a support, a temporary fixing material and a workpiece wherein the temporary fixing material includes a layer (I) that contains a polymer (A) including a structural unit (A1); a step of processing the workpiece and/or transporting the stack; a step of applying light to the layer (I) through the support; and a step of separating the support and the workpiece from each other. ##STR00001##

In a method in which a workpiece, while being temporarily fixed on a support via a temporary fixing material, is processed and/or transported and thereafter the support and the workpiece are separated from each other by an irradiation separation method, a technique is shown which prevents the photo-degradation of the workpiece. A workpiece treating method includes a step of forming a stack including a support, a temporary fixing material and a workpiece wherein the temporary fixing material includes a layer (I) that contains a polymer (A) including a structural unit (A1); a step of processing the workpiece and/or transporting the stack; a step of applying light to the layer (I) through the support; and a step of separating the support and the workpiece from each other. ##STR00001##

Diazo-resin-containing photoresist compositions and methods of preparing the same are provided for solving the problem that existing diazo-resins cannot be applied in LCD photoresists because the storage periods of the diazo-resins themselves and the printed boards made thereby are both short due to poor thermal stability of the diazo-resins. The diazo-resins of the present invention have excellent thermal stability and exhibit strong resistance to dry etching when being used in negative photoresists, while high resolution can be achieved. Meanwhile, during exposure, portions of the diazo-resins can crosslink with hydrogen bonds on surface of SiO or SiON film forming a barrier layer or passivation layer, such that the adhesion between the photoresists and the film layer is increased, and the photoresists would not peel during development. Thus, the utilization of tackifiers for enhancing the adhesion between a photoresist and surface of SiO or SiON film before masking can be omitted.

Diazo-resin-containing photoresist compositions and methods of preparing the same are provided for solving the problem that existing diazo-resins cannot be applied in LCD photoresists because the storage periods of the diazo-resins themselves and the printed boards made thereby are both short due to poor thermal stability of the diazo-resins. The diazo-resins of the present invention have excellent thermal stability and exhibit strong resistance to dry etching when being used in negative photoresists, while high resolution can be achieved. Meanwhile, during exposure, portions of the diazo-resins can crosslink with hydrogen bonds on surface of SiO or SiON film forming a barrier layer or passivation layer, such that the adhesion between the photoresists and the film layer is increased, and the photoresists would not peel during development. Thus, the utilization of tackifiers for enhancing the adhesion between a photoresist and surface of SiO or SiON film before masking can be omitted.

In a method in which a workpiece, while being temporarily fixed on a support via a temporary fixing material, is processed and/or transported and thereafter the support and the workpiece are separated from each other by an irradiation separation method, a technique is shown which prevents the photo-degradation of the workpiece.

A workpiece treating method includes a step of forming a stack including a support, a temporary fixing material and a workpiece wherein the temporary fixing material includes a layer (I) that contains a polymer (A) including a structural unit (A1); a step of processing the workpiece and/or transporting the stack; a step of applying light to the layer (I) through the support; and a step of separating the support and the workpiece from each other.

##STR00001##