Compositions, thermally-insulating layers, and direct thermally imaging members containing the same

Abstract

Multicolor thermal imaging members are described that comprise color-forming layers that are separated by thermally-insulating layers and can be addressed with a thermal printing head in contact with a surface to form an image. The thermally-insulating layers are designed to be as thin as possible consistent with at least partially independent addressing of the color-forming layers, and are formulated so as not to lead to instabilities either before or after printing or to give rise to dimensional changes of a thermal imaging member when it is subjected to changes in temperature or humidity. Coating compositions for manufacturing such thermally-insulating layers are also provided.

1 - 13 . (canceled) 
     
     
         14 . An apparatus comprising a coating composition wherein the coating composition comprises
 at least 20% by weight of water-borne latex polymeric material,   less than 20% by weight of a hydrophobically-modified poly(vinyl alcohol), and   percentages by weight are relative to the total weight of the coating composition.   
     
     
         15 . The apparatus of  claim 14 , wherein the coating composition comprises at least 30% by weight of water-borne latex polymeric material and less than 10% by weight of a hydrophobically-modified poly(vinyl alcohol). 
     
     
         16 . The apparatus of  claim 14 , wherein the coating composition further comprises an organic material that has a glass transition temperature of at least 80° C. in an amount that is at least 10% of the weight of the polymeric latex material, and wherein the organic material comprises phenolic materials having a molecular weight below 2,000. 
     
     
         17 . The apparatus of  claim 16 , wherein the organic material is chosen from the group consisting of 1,3,5-tris(2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl)isocyanurate and 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane. 
     
     
         18 . The apparatus of  claim 14 , wherein the apparatus comprises a thermal imaging member. 
     
     
         19 . The apparatus of  claim 14 , wherein
 the viscosity of the coating composition measured at 1000 s −1  is more than 50 mPa·s,   the flow behavior index n is within the range of 0.8 to 1, and   the water-borne latex polymeric material has a Tg in the range of about 15-35° C.   
     
     
         20 . The apparatus of  claim 16 , wherein the coating composition further comprises an additive selected from the group consisting of an anionic surfactant, an ethoxylated non-ionic fluorinated surfactant, dispersed inorganic particles, a crosslinking agent, and combinations thereof. 
     
     
         21 . The apparatus of  claim 20 , wherein the anionic surfactant is triisopropyl naphthalene sulfonate. 
     
     
         22 . The apparatus of  claim 20 , wherein the crosslinking agent is selected from the group consisting of an epoxide, aziridine, isocyanate, anhydride, aldehyde and combinations thereof. 
     
     
         23 . The apparatus of  claim 20 , wherein the dispersed inorganic particles comprise clay materials.