Process and apparatus for microreplication

Abstract

A method of embossing a sheet material includes: heating at least a portion of the sheet directly or indirectly with radiant energy from a radiant energy source; pressing a tool against the heated portion of the sheet, thereby patterning a surface of the sheet; and separating the sheet and the tool. The radiant energy may travel through a solid material that is relatively transparent to radiation, on its way to being absorbed by a relatively-absorptive material. The relatively-transparent material may be an unheated portion of the sheet, and the relatively-absorptive material may be either the tool or the heated portion of the sheet. Alternatively, the relatively-transparent material may be the tool, and the relatively-absorptive material may be all or part of the sheet. The method may be performed as one or more roll-to-roll operations.

1 . An embossing system, comprising:
 a plurality of rollers, arrayed on opposite sides of a passage for receiving therein a sheet material to be embossed;   a radiant heater operatively configured to heat the sheet material while in the passage; and   a patterned belt in the passage, for patterning the sheet material.   
   
   
       2 . The system of  claim 1 ,
 wherein the radiant heater includes radiant energy sources; and   wherein the radiant heater further includes one or more reflectors operatively coupled to the at least some of the radiant energy sources, to thereby direct radiant energy from the radiant energy sources to the passage.   
   
   
       3 . The system of  claim 2 ,
 wherein in radiant energy sources and the reflectors are in at least some of the rollers; and   wherein the at least some of the rollers include radiantly-transparent roller material that allows radiant energy from the radiant energy sources to pass therethrough.   
   
   
       4 . The system of  claim 1 ,
 wherein in radiant energy sources are in at least some of the rollers; and   wherein the at least some of the rollers include radiantly-transparent roller material that allows radiant energy from the radiant energy sources to pass therethrough.   
   
   
       5 . An embossing system, comprising:
 a pair of belts arrayed on opposite sides of a passage for receiving therein a sheet material to be embossed; and   a radiant heater operatively configured to heat the sheet material while in the passage.   
   
   
       6 . The system of  claim 5 ,
 wherein one of the belts includes a radiantly-transparent material; and   wherein the radiant heater is configured to pass radiant energy into the passage through the radiantly-transparent material.   
   
   
       7 . The system of  claim 6 , wherein the other belt includes a radiantly-absorptive material. 
   
   
       8 . The system of  claim 5 ,
 wherein the radiant heater includes:
 at least one radiant energy source that produces radiant energy; and 
 at least one reflector; and 
   wherein the at least one radiant energy source and the at least one reflector are configured such that the at least reflector directs at least some of the radiant energy toward the passage.   
   
   
       9 . An embossing system, comprising:
 a pair of press platforms configured to press a sheet material therebetween; and   a radiant heater configured to deliver radiant energy between the press platforms.   
   
   
       10 . The system of  claim 9 ,
 wherein one of the press platforms includes a radiantly-transparent material; and   wherein the radiant heater is configured to pass the radiant energy through the radiantly-transparent material.   
   
   
       11 . The system of  claim 10 , further comprising a pressure-producing device operatively coupled to the press platforms to press the platforms together.