Process for producing sandwich structure and adhesive film therefor

Abstract

A process for producing a sandwich structure, includes laminating a reinforced fiber material which is substantially free from a matrix resin; a glycol modified copolymerized polyester resin film; a thermosetting resin composition film which is hardened at room temperature; a core material selected from an open cell foam and a honeycomb; a thermosetting resin composition film which is hardened at room temperature; a glycol modified copolymerized polyester resin film; and a reinforced fiber material which is substantially free from a matrix resin, in this order in a molding tool to form a sandwich, hardening the thermosetting resin composition film which is hardened at room temperature under a condition that the molding tool is closed, infusing a matrix resin into the molding tool, and adjusting a temperature in the molding tool at room temperature or a hardening temperature of the matrix resin to harden the matrix resin.

1 . A process for producing a sandwich structure comprising: 
 laminating a reinforced fiber material which is substantially free from a matrix resin; a glycol modified copolymerized polyester resin film; a thermosetting resin composition film which is hardened at room temperature; a core material selected from an open cell foam and a honeycomb; a thermosetting resin composition film which is hardened at room temperature; a glycol modified copolymerized polyester resin film; and a reinforced fiber material which is substantially free from a matrix resin, in this order in a molding tool to form a sandwich,    hardening the thermosetting resin composition film which is hardened at room temperature under a condition that the molding tool is closed,    infusing a matrix resin into the molding tool, and    adjusting a temperature in the molding tool at room temperature or a hardening temperature of the matrix resin to harden the matrix resin.    
   
   
       2 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the glycol modified copolymerized polyester resin is a cycloalkanediol modified copolymerized polyester resin.  
   
   
       3 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the glycol modified copolymerized polyester resin is a cycloalkanediol modified copolymerized polyethylene terephthalate resin.  
   
   
       4 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the glycol modified copolymerized polyester resin film and the thermosetting resin composition film which is hardened at room temperature previously form an adhesive film consisting of the glycol modified copolymerized polyester resin film and a thermosetting resin composition which is hardened at room temperature, which is held uniformly thereon.  
   
   
       5 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the thermosetting resin composition film which is hardened at room temperature has a cloth as a carrier.  
   
   
       6 . A process for producing a sandwich structure as set forth in  claim 5 , wherein the cloth used as the carrier is a nonwoven fabric.  
   
   
       7 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the thermosetting resin composition which forms the thermosetting resin composition film which is hardened at room temperature has a viscosity of 2 to 200 Pa·S.  
   
   
       8 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the thermosetting resin composition which forms the thermosetting resin composition film which is hardened at room temperature consists of a vinyl polymerizable compound.  
   
   
       9 . A process for producing a sandwich structure as set forth in  claim 8 , wherein the vinyl polymerizable compound is a vinyl ester resin.  
   
   
       10 . A process for producing a sandwich structure as set forth in  claim 8 , wherein the thermosetting resin composition which forms the thermosetting resin composition film which is hardened at room temperature contains a viscosity increasing agent.  
   
   
       11 . A process for producing a sandwich structure as set forth in  claim 10 , wherein the viscosity increasing agent is polyethylene oxide.  
   
   
       12 . A process for producing a sandwich structure as set forth in  claim 8 , wherein the thermosetting resin composition which forms the thermosetting resin composition film which is hardened at room temperature contains a polymerization retardant or inhibitor.  
   
   
       13 . A process for producing a sandwich structure as set forth in  claim 12 , wherein the polymerization retardant or inhibitor is 4-methoxyphenol.  
   
   
       14 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the molding tool is a molding tool which can depressurize the interior thereof.  
   
   
       15 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the hardening the thermosetting resin composition film which is hardened at room temperature is performed under a depressurized state.  
   
   
       16 . A process for producing a sandwich structure as set forth in  claim 1 , further comprising pressing an upper molding tool and/or a lower molding tool between laminating a reinforced fiber material which is substantially free from a matrix resin; 
 a glycol modified copolymerization polyester resin film; a thermosetting resin composition film which is hardened at room temperature; a core material selected from an open cell foam and a honeycomb; a thermosetting resin composition film which is hardened at room temperature; a glycol modified copolymerization polyester resin film; and a reinforced fiber material which is substantially free from a matrix resin, in this order in a molding tool to form a sandwich, and    hardening the thermosetting resin composition film which is hardened at room temperature under a condition that the molding tool is closed.    
   
   
       17 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the matrix resin is a vinyl ester resin.  
   
   
       18 . A process for producing a sandwich structure as set forth in  claim 1 , wherein the matrix resin is an epoxy resin.  
   
   
       19 . A process for producing a sandwich structure as set forth in  claim 1 , wherein a frame member which prevents the matrix resin from penetrating into the core material is disposed at the circumference of the core material.  
   
   
       20 . An adhesive film, comprising a glycol modified copolymerized polyester resin film, and a thermosetting resin composition which is hardened at room temperature, which is held uniformly on the glycol modified copolymerized polyester resin film.