Process for heat setting polyester fibers for sublimation printing

Abstract

The processes and articles of the present invention use thermally stable and loft retentive polymers in sublimation printed flock fibers, which are particularly attractive for forming molded and heat laminated articles. The process and articles use high, medium and low energy dyes on the fibers. A preferred polymer for use in the fibers is poly(cyclohexylene-dimethylene terephthalate). The fibers are heat set before sublimation printing.

1 . A method for forming a flocked article, comprising: 
 forming a flocked article comprising a plurality of crystalline flock fibers;    heat setting the flock fibers at a temperature in excess of a maximum sublimation printing temperature; and    thereafter sublimation printing the heat set flock fibers at a temperature at or below the maximum sublimation printing temperature.    
   
   
       2 . The method of  claim 1 , wherein the flocked article comprises at least one of a substrate and a carrier, the at least one of a substrate and carrier being adhered to the fibers by an adhesive, wherein the fibers comprise poly(cyclohexylene-dimethylene terephthalate), wherein the fibers are free-standing and oriented transversely to the adjacent surface of the substrate, and wherein the fibers comprise at least one of a medium and high energy sublimation dye.  
   
   
       3 . The method of  claim 2 , wherein the at least one of a medium and high energy dye is a medium energy dye.  
   
   
       4 . The method of  claim 1 , wherein the heat set temperature is at least about 215° C.  
   
   
       5 . The method of  claim 2 , wherein the at least one of a medium and high energy dye is a high energy dye.  
   
   
       6 . The method of  claim 4 , wherein the heat set temperature is at least about 220° C.  
   
   
       7 . A method, comprising: 
 providing a carrier, the carrier comprising a carrier substrate and a release adhesive;    applying flock fibers to the carrier, wherein the flock fibers contact the first surface of the release adhesive and have first and second ends, the second ends being adhered to the first surface of the release adhesive;    thereafter heat setting the flock fibers at a temperature above a maximum printing temperature;    providing a sublimation ink comprising dye particles;    contacting the heat set flock fibers with dye particles at a first temperature;    during and/or after the contacting step, thermofixing, at a second temperature, the dye particles in the sublimation ink to the fibers to color the fibers, wherein the first and second temperatures are no more than the maximum printing temperature; and    thereafter applying a permanent adhesive to the first ends of the fibers.    
   
   
       8 . The method of  claim 7 , wherein the release adhesive is at least one of a pressure sensitive adhesive and hot melt adhesive and wherein the permanent adhesive is at least one of a thermoplastic and thermoset adhesive, and wherein first temperature is less than the second temperature.  
   
   
       9 . The method of  claim 7 , wherein the flock fibers, before heat setting, comprise a crystalline polyester.  
   
   
       10 . The method of  claim 9 , wherein the crystalline polyester comprises poly(cyclohexylene-dimethylene terephthalate), wherein the fibers are free-standing and oriented transversely to the adjacent surface of the substrate, and wherein the fibers comprise at least one of a medium and high energy sublimation dye.  
   
   
       11 . The method of  claim 7 , wherein the heat set temperature is at least about 215° C.  
   
   
       12 . The method of  claim 7 , wherein the heat set temperature is at least about 220° C.  
   
   
       13 . The method of  claim 7 , wherein the sublimation dye ink comprises at least one of a medium energy and high energy dye.  
   
   
       14 . The method of  claim 7 , wherein the fibers comprise at least about 25 wt. % of a terephthalate polymer and/or copolymer having a repeating unit of the formula of  FIG. 15  or  23 , where “R” represents independently hydrogen or a substituted or unsubstituted alkyl or aryl group and “S” is an aromatic or nonaromatic cyclic residue which can include one or more hereoatoms.  
   
   
       15 . The method of  claim 7 , wherein the flock fibers comprise a polymer, wherein the polymer has a glass transition temperature of at least about 75° C., and wherein the fibers have an aspect ratio similar to that of nylon and a denier of from about 2 to about 50.  
   
   
       16 . The method of  claim 12 , wherein the polymer is poly(cyclohexylene-dimethylene terephthalate and the fibers are flock.