Resin forming method and resin forming apparatus

Abstract

The present invention presents a resin forming method and a resin forming apparatus 1 for obtaining a resin formed product, by filling a cavity 21 of a rubber-made mold 2 with a thermoplastic resin 3 , and cooling this thermoplastic resin 3 . When filling the cavity 21 with the thermoplastic resin 3 , electromagnetic wave generating means 4 is used, and electromagnetic waves having an intensity peak in a wavelength region of 0.78 to 2 μm are irradiated to the thermoplastic resin 3 from the surface of the mold 2 , and thereby the thermoplastic resin 3 is heated selectively from the mold 2 . The thermoplastic resin 3 is an ABS resin which either a noncrystalline thermoplastic resin, or is a rubber modified thermoplastic resin.

1 . A resin forming method for obtaining a resin formed product by filling a cavity of a rubber-made mold with a thermoplastic resin and cooling the thermoplastic resin,
 wherein the thermoplastic resin is heated by irradiating electromagnetic waves of 0.78 to 2 μm in wavelength to the thermoplastic resin from the surface of the mold when filling the cavity with the thermoplastic resin.   
     
     
         2 . The resin forming method according to  claim 1 ,
 wherein electromagnetic wave generating means for outputting electromagnetic waves of 0.78 to 4 μm in wavelength, and a filter for decreasing the transmission amount of electromagnetic waves exceeding 2 μm in wavelength are used, and the electromagnetic waves output from the electromagnetic wave generating means are passed through the filter, and the transmission electromagnetic waves after passing through the filter are irradiated to the thermoplastic resin through the mold, and thereby the thermoplastic resin is heated, when filling the cavity with the thermoplastic resin.   
     
     
         3 . The resin forming method according to  claim 1 , comprising:
 a vacuum step of vacuating the cavity in the rubber-made mold,   a filling step of filling the vacuated cavity with a melted thermoplastic resin, and   a cooling step of cooling the thermoplastic resin in the cavity and obtaining the resin formed product,   wherein the filling step is characterized by heating the thermoplastic resin by irradiating electromagnetic waves of 0.78 to 2 μm in wavelength to the thermoplastic resin through the mold.   
     
     
         4 . The resin forming method according to  claim 1 , comprising:
 a vacuum step of vacuating the cavity in the rubber-made mold,   a filling step of filling the vacuated cavity with a melted thermoplastic resin, and   a cooling step of cooling the thermoplastic resin in the cavity and obtaining the resin formed product,   wherein the filling step is characterized by using electromagnetic wave generating means for outputting electromagnetic waves of 0.78 to 4 μm in wavelength, and a filter for decreasing the transmission amount of electromagnetic waves exceeding 2 μm in wavelength, and the electromagnetic waves output from the electromagnetic wave generating means are passed through the filter, and the transmission electromagnetic waves after passing through the filter are irradiated to the thermoplastic resin through the mold, and thereby the thermoplastic resin is heated.   
     
     
         5 . The resin forming method according to  claim 2 , wherein the filter is a quartz glass capable of decreasing the transmission amount of electromagnetic waves exceeding 2 μm in wavelength. 
     
     
         6 . The resin forming method according to  claim 1 , wherein the electromagnetic waves have an intensity peak in a wavelength region of 0.78 to 2 μm. 
     
     
         7 . The resin forming method according to  claim 1 , wherein the thermoplastic resin is heated to a higher temperature than the mold. 
     
     
         8 . The resin forming method according to  claim 1 , wherein the thermoplastic resin in a melted state is cast into the cavity of the mold, and
 the viscosity of the thermoplastic resin in the melted state is prevented from becoming higher than 5000 Poise.   
     
     
         9 . The resin forming method according to  claim 3 , wherein the mold is disposed in a pressure vessel capable of increasing and decreasing in pressure, and
 the pressure in the pressure vessel is decreased at the vacuum step to vacuate the cavity, and after the thermoplastic resin is cast into the cavity at the filling step, the inside of the pressure vessel is increased in pressure from the vacuum state.   
     
     
         10 . The resin forming method according to  claim 1 , wherein the thermoplastic resin before being filled into the cavity is a resin solid material formed larger than in a capacity for filling in the cavity, and
 the cavity is filled with the thermoplastic resin melted from the resin solid material, by making use of the own gravity of the thermoplastic resin.   
     
     
         11 . The resin forming method according to  claim 1 , wherein an absorbance of the thermoplastic resin is larger than an absorbance of the rubber-made mold. 
     
     
         12 . The resin forming method according to  claim 1 , wherein the thermoplastic resin is a noncrystalline thermoplastic resin. 
     
     
         13 . The resin forming method according to  claim 1 , wherein the thermoplastic resin is a rubber modified thermoplastic resin. 
     
     
         14 . The resin forming method according to  claim 1 , wherein the mold is formed of silicone rubber. 
     
     
         15 - 27 . (canceled)