Resin powder, method for its production, composite, molded product, method for producing ceramic molded product, metal laminated plate, printed circuit board and prepreg

Abstract

To provide a method capable of producing, by means of mechanical pulverization, a resin powder having a high bulk density and an average particle size of at most 50 μm from resin particles containing a fluorocopolymer as the main component and having a melting point of from 260 to 320° C., such as PFA. The method is to obtain a resin powder having an average particle size of from 0.02 to 50 μm by subjecting resin particles (A) having an average particle size of at least 100 μm to mechanical pulverization treatment. The resin particles (A) is made of a material (X) having a fluorocopolymer (X1) as the main component; and said fluorocopolymer (X1) has a unit (1) based on a monomer containing at least one type of functional group selected from the group consisting of a carbonyl group-containing group, a hydroxy group, an epoxy group and an isocyanate group, and a unit (2) based on tetrafluoroethylene, and has a melting point of from 260 to 320° C.

What is claimed is: 
     
         1 . A method for obtaining a resin powder having an average particle size of from 0.02 to 50 μm, which comprises subjecting resin particles (A) having an average particle size of at least 100 μm to mechanical pulverization treatment, and which is characterized in that the resin particles (A) are made of a material (X) containing the following fluorocopolymer (X1) as the main component:
 Fluorocopolymer (X1): a fluorocopolymer which has a unit (1) containing at least one type of functional group selected from the group consisting of a carbonyl group-containing group, a hydroxy group, an epoxy group and an isocyanate group, and a unit (2) based on tetrafluoroethylene, and which has a melting point of from 260 to 320° C. 
 
     
     
         2 . The method for obtaining a resin powder according to  claim 1 , wherein the fluorocopolymer (X1) is the following fluorocopolymer (X1-1):
 Fluorocopolymer (X1-1): a fluorocopolymer which has the unit (1), the unit (2) and a unit (3-1) based on a perfluoro(alkyl vinyl ether), wherein to the total of all units, the proportion of the unit (1) is from 0.01 to 3 mol %, the proportion of the unit (2) is from 90 to 99.89 mol %, and the proportion of the unit (3-1) is from 0.1 to 9.99 mol %, and which has a melting point of from 260 to 320° C.   
     
     
         3 . The method for obtaining a resin powder according to  claim 1 , wherein the fluorocopolymer (X1) is the following fluorocopolymer (X1-2):
 Fluorocopolymer (X1-2): a fluorocopolymer which has the unit (1), the unit (2) and a unit (3-2) based on hexafluoropropylene, wherein to the total of all units, the proportion of the unit (1) is from 0.01 to 3 mol %, the proportion of the unit (2) is from 90 to 99.89 mol %, and the proportion of the unit (3-2) is from 0.1 to 9.99 mol %, and which has a melting point of from 260 to 320° C.   
     
     
         4 . The method for obtaining a resin powder according to  claim 1 , wherein the unit (1) includes a unit containing a carbonyl group-containing group, and
 said carbonyl group-containing group is at least one member selected from the group consisting of a group having a carbonyl group between carbon atoms in a hydrocarbon group, a carbonate group, a carboxy group, a haloformyl group, an alkoxy carbonyl group and an acid anhydride residue group.   
     
     
         5 . The method for obtaining a resin powder according to  claim 1 , wherein the average particle size of the resin powder is from 0.02 to 10 μm. 
     
     
         6 . The method for obtaining a resin powder according to  claim 1 , wherein the average particle size of the resin powder is from 0.02 to 6 μm, and D90 is at most 8 μm. 
     
     
         7 . The method for obtaining a resin powder according to  claim 1 , wherein the mechanical pulverization treatment is conducted after cooling the resin particles (A) to a temperature of at most −40° C., or conducted by using a jet mill. 
     
     
         8 . The method for obtaining a resin powder according to  claim 7 , wherein the mechanical pulverization treatment is conducted by using a jet mill. 
     
     
         9 . A method for producing a composite, which comprises producing a resin powder by the method for obtaining a resin powder as defined in  claim 1 , and dispersing the obtained resin powder in a resin (C) (but excluding the fluorocopolymer (X1)). 
     
     
         10 . The method for producing a composite according to  claim 9 , wherein the resin (C) is a thermosetting resin or a photosensitive resin. 
     
     
         11 . The method for producing a composite according to  claim 10 , wherein the resin (C) is a thermosetting resin, and the thermosetting resin comprises at least one member selected from the group consisting of a polyimide and an epoxy resin. 
     
     
         12 . The method for producing a composite according to  claim 11 , wherein the relative dielectric constant (value measured at a frequency of 2.5 GHz in an environment within a range of 23° C.±2° C. and RH of 50±5%) is from 2.0 to 3.5. 
     
     
         13 . The method for producing a composite according to  claim 9 , which is used to form at least one of an interlayer insulating film of a printed circuit board, a cover lay film and a solder resist. 
     
     
         14 . A method for producing a molded product, which comprises producing a composite by the method for producing a composite as defined in  claim 9 , and molding the obtained composite. 
     
     
         15 . A method for producing a ceramic molded product, which comprises steps of producing a resin powder by the production method as defined in  claim 1 , mixing the obtained resin powder and a ceramic powder to obtain a mixture, and molding the mixture to obtain a ceramic molded product. 
     
     
         16 . A method for producing a metal laminated plate, which comprises producing a molded product by the production method as defined in  claim 14 , and laminating a metal layer on one side or both sides of a substrate made of the obtained molded product. 
     
     
         17 . A method for producing a printed circuit board, which comprises producing a metal laminated plate by the production method as defined in  claim 16 , and etching the metal layer of the obtained metal laminated plate to form a patterned circuit. 
     
     
         18 . A method for producing a prepreg, which comprises producing a resin powder by the production method as defined in  claim 1 , and impregnating at least one member selected from the group consisting of a thermosetting resin composition containing the obtained resin powder and a thermoplastic resin composition containing the obtained resin powder, in a fiber substrate. 
     
     
         19 . A method for producing an adhesive film, which comprises laminating a layer made of the composite obtained by the production method as defined in  claim 9  on at least one side of a heat-resistant resin film, wherein the resin powder has an average particle size of from 0.02 to 6 μm and D90 of at most 8 μm, and the relative dielectric constant (value measured at a frequency of 2.5 GHz in an environment within a range of 23° C.±2° C. and RH of 50±5%) of the adhesive layer is from 2.0 to 3.5. 
     
     
         20 . A method of producing a metal laminated plate, which comprises laminating a metal layer on at least one layer made of the layer of the composite of the adhesive film obtained by the production method as defined in  claim 19 . 
     
     
         21 . An adhesive film in which a layer made of a composite having a resin powder made of a material (X) containing a fluorocopolymer (X1) as the main component dispersed in a resin (C) (but excluding the fluorocopolymer (X1)), is laminated on at least one side of a heat-resistant resin film, wherein
 the fluorocopolymer (X1) has a unit (1) containing at least one type of functional group selected from the group consisting of a carbonyl group-containing group, a hydroxy group, an epoxy group and an isocyanate group, and a unit (2) based on tetrafluoroethylene, and has a melting point of from 260 to 320° C.; the resin powder has an average particle size of from 0.02 to 6 μm and D90 of at most 8 μm; and the relative dielectric constant (value measured at a frequency of 2.5 GHz in an environment within a range of 23° C.±2° C. and RH of 50±5%) of the adhesive film is from 2.0 to 3.5.   
     
     
         22 . A metal laminated plate having a metal layer directly laminated on at least one layer made of the layer of the composite of the adhesive film as defined in  claim 21 . 
     
     
         23 . A composite to be used for forming at least one member selected from the group consisting of an interlayer insulating film of a printed circuit board, a cover lay film and a solder resist,
 said composite being a composite in which a resin powder made of a material (X) containing a fluorocopolymer (X1) as the main component is dispersed in a resin (C) (but excluding the fluorocopolymer (X1)), wherein the fluorocopolymer (X1) has a unit (1) containing at least one type of functional group selected from the group consisting of a carbonyl group-containing group, a hydroxy group, an epoxy group and an isocyanate group, and a unit (2) based on tetrafluoroethylene, and has a melting point of from 260 to 320° C.; the resin powder has an average particle size of from 0.02 to 6 μm and D90 of at most 8 μm; and the relative dielectric constant (value measured at a frequency of 2.5 GHz in an environment within a range of 23° C.±2° C. and RH of 50±5%) of the composite is from 2.0 to 3.5.   
     
     
         24 . A prepreg in which at least one member selected from the group consisting of a thermosetting resin composition containing a resin powder, and a thermoplastic resin composition containing a resin powder, is impregnated in a fiber substrate, wherein
 said at least one member selected from the group consisting of the thermosetting resin composition and the thermoplastic resin composition, is a composite in which a resin powder made of a material (X) containing a fluorocopolymer (X1) as the main component is dispersed in a resin (C) (but excluding the fluorocopolymer (X1)); the fluorocopolymer (X1) has a unit (1) containing at least one type of functional group selected from the group consisting of a carbonyl group-containing group, a hydroxy group, an epoxy group and an isocyanate group, and a unit (2) based on tetrafluoroethylene, and has a melting point of from 260 to 320° C.; the resin powder has an average particle size of from 0.02 to 6 μm and D90 of at most 8 μm; and the relative dielectric constant (value measured at a frequency of 2.5 GHz in an environment within a range of 23° C.±2° C. and RH of 50±5%) of the thermosetting resin composition and/or the thermoplastic resin composition is from 2.0 to 3.5.   
     
     
         25 . A metal laminated plate having a metal layer laminated on one side or both sides of the prepreg as defined in  claim 24 .