Heat-transfer label including non-wax release layer

Abstract

A heat-transfer label including a non-wax, non-silicone release layer for use in decorating an article, such as a glass container, without leaving a visually discernible release residue on the decorated article. In a preferred embodiment, the label includes a transfer portion, the transfer portion comprising a protective lacquer layer, an ink design layer over the protective lacquer layer, and a heat-activatable adhesive layer over the ink design and protective lacquer layers, the adhesive layer extending beyond the peripheries of the ink design and protective lacquer layers. The protective lacquer layer preferably includes a cross-linked phenoxy resin, the ink design layer preferably includes a polyester resin, and the adhesive layer preferably includes a polyester resin and an anti-blocking agent, such as a paraffinic wax. The label also includes a support portion, the transfer portion being positioned over the support portion for transfer of the transfer portion from the support portion to an article upon the application of heat to the support portion while the transfer portion is placed in contact with the article. The support portion includes a carrier, the carrier preferably being a polyester film. The support portion also includes a non-wax, non-silicone release layer positioned over the carrier and in direct contact with the protective lacquer layer and the periphery of the adhesive layer, the release layer preferably being made by (a) coating onto the carrier a composition preferably comprising about 5 to 30 wt % of an alkyl vinyl ether monomer having a carbon chain length of at least 18, about 40 to 80 wt % of a difunctional acrylate monomer, about 5 to 50 wt % of trifunctional acrylate monomer, and about 2 to 8 wt % of a free-radical UV photoinitiator and (b) activating the free-radical UV photoinitator. The release composition may also include up to about 1 wt % of a wetting agent, such as a fluoroalkyl surfactant, a silicone polyether wetting agent, and a silicone defoamer.

What is claimed is:  
     
         1 . A heat-transfer label comprising: 
 (a) a transfer portion, said transfer portion comprising 
 (i) a protective lacquer layer,  
 (ii) an ink design layer over said protective lacquer layer, and  
 (iii) a heat-activatable adhesive layer over said ink design and protective lacquer layers, said heat-activatable adhesive layer extending beyond the peripheries of said ink design and protective lacquer layers; and  
   (b) a support portion, said transfer portion being positioned over said support portion for transfer, under conditions of heat and pressure, of the transfer portion from the support portion to an article, said support portion comprising 
 (i) a carrier, and  
 (ii) a release layer positioned over said carrier, said release layer being made of a non-wax, non-silicone, thermoset release material, said release layer separating cleanly from said transfer portion with no visually discernible portion of said release layer being transferred to the article along with said transfer portion.  
   
     
     
         2 . The heat-transfer label as claimed in  claim 1  wherein said release layer is in direct contact with said transfer portion.  
     
     
         3 . The heat-transfer label as claimed in  claim 1  wherein said release layer is in direct contact with each of said protective lacquer layer and the periphery of said heat-activatable adhesive layer.  
     
     
         4 . The heat-transfer label as claimed in  claim 3  wherein said release layer is made by (a) coating onto said carrier a composition comprising (i) a functionalized alkyl monomer having a carbon chain length of at least 18 carbon atoms, (ii) a crosslinking monomer reactive with said functionalized alkyl monomer, and (iii) an initiator for effecting at least a partial cure between said functionalized alkyl monomer and said crosslinking monomer and (b) activating said initiator.  
     
     
         5 . The heat-transfer label as claimed in  claim 4  wherein said functionalized alkyl monomer is an alkyl vinyl ether monomer and wherein said crosslinking monomer comprises at least one multifunctional acrylate monomer.  
     
     
         6 . The heat-transfer label as claimed in  claim 3  wherein said release layer is made by (a) coating onto said carrier a composition comprising (i) an alkyl vinyl ether monomer of the formula C n H 2n+1 O—CH═CH wherein n is at least 18, (ii) a trifunctional acrylate monomer, (iii) a difunctional acrylate monomer and (iv) a free-radical initiator and (b) activating said free radical initiator.  
     
     
         7 . The heat-transfer label as claimed in  claim 6  wherein n is not greater than 30.  
     
     
         8 . The heat-transfer label as claimed in  claim 7  wherein n is equal to 18.  
     
     
         9 . The heat-transfer label as claimed in  claim 6  wherein said trifunctional acrylate monomer is propoxylated trimethylolpropane triacrylate.  
     
     
         10 . The heat-transfer label as claimed in  claim 6  wherein said difunctional acrylate monomer is propoxylated neopentyl glycol diacrylate.  
     
     
         11 . The heat-transfer label as claimed in  claim 6  wherein said free radical initiator is a free-radical photoinitiator.  
     
     
         12 . The heat-transfer label as claimed in  claim 11  wherein said free radical photoinitiator is a free-radical UV photoinitiator.  
     
     
         13 . The heat-transfer label as claimed in  claim 6  wherein said composition further comprises a wetting agent.  
     
     
         14 . The heat-transfer label as claimed in  claim 13  wherein said wetting agent is selected from the group consisting of fluoroalkyl surfactants, silicone polyether wetting agents, and silicone defoamers.  
     
     
         15 . The heat-transfer label as claimed in  claim 6  wherein said composition comprises about 5 to 30 wt % of said alkyl vinyl ether monomer, about 40 to 80 wt % of said difunctional acrylate monomer, about 5 to 50 wt % of said trifunctional acrylate monomer and about 2 to 8 wt % of said free-radical initiator.  
     
     
         16 . The heat-transfer label as claimed in  claim 15  wherein said composition further comprises a wetting agent in an amount constituting about 0.1 to 1.0 wt % of said composition.  
     
     
         17 . The heat-transfer label as claimed in  claim 16  wherein said wetting agent is selected from the group consisting of fluoroalkyl surfactants, silicone polyether wetting agents, and silicone defoamers.  
     
     
         18 . The heat-transfer label as claimed in  claim 15  wherein said composition comprises about 10 to 20 wt % of said alkyl vinyl ether monomer, about 60 to 70 wt % of said difunctional acrylate monomer, about 10 to 30 wt % of said trifunctional acrylate monomer and about 3 to 6 wt % of said free-radical initiator.  
     
     
         19 . The heat-transfer label as claimed in  claim 1  wherein said carrier comprises a plastic film.  
     
     
         20 . The heat-transfer label as claimed in  claim 19  wherein said carrier is a polyester film.  
     
     
         21 . The heat-transfer label as claimed in  claim 20  wherein said polyester film is transparent.  
     
     
         22 . The heat-transfer label as claimed in  claim 1  wherein said heat-activatable adhesive comprises a polyester resin.  
     
     
         23 . The heat-transfer label as claimed in  claim 15  wherein said heat-activatable adhesive comprises a polyester resin.  
     
     
         24 . A release coating composition comprising: 
 (a) an alkyl vinyl ether monomer having a carbon chain length of at least 18 carbon atoms;    (b) a crosslinker reactive with said alkyl vinyl ether monomer, said crosslinker comprising at least one multifunctional acrylate monomer reactive with said alkyl vinyl ether monomer; and    (c) an initiator for effecting at least a partial cure between said alkyl vinyl ether monomer and said crosslinker.    
     
     
         25 . The release coating composition as claimed in  claim 24  wherein said crosslinker comprises a difunctional acrylate monomer and a trifunctional acrylate monomer.  
     
     
         26 . The release coating composition as claimed in  claim 25  wherein said alkyl vinyl ether monomer has a carbon chain length of no greater than 30.  
     
     
         27 . The release coating composition as claimed in  claim 26  wherein said alkyl vinyl ether monomer has a carbon chain length equal to 18.  
     
     
         28 . The release coating composition as claimed in  claim 26  wherein said trifunctional acrylate monomer is propoxylated trimethylolpropane triacrylate.  
     
     
         29 . The release coating composition as claimed in  claim 26  wherein said difunctional acrylate monomer is propoxylated neopentyl glycol diacrylate.  
     
     
         30 . The release coating composition as claimed in  claim 26  wherein said initiator is a free-radical initiator.  
     
     
         31 . The release coating composition as claimed in  claim 30  wherein said free radical initiator is a free-radical photoinitiator.  
     
     
         32 . The release coating composition as claimed in  claim 31  wherein said free radical initiator is a free-radical UV photoinitiator.  
     
     
         33 . The release coating composition as claimed in  claim 30  wherein said composition comprises about 5 to 30 wt % of said alkyl vinyl ether monomer, about 40 to 80 wt % of said difunctional acrylate monomer, about 5 to 50 wt % of said trifunctional acrylate monomer and about 2 to 8 wt % of said free-radical initiator.  
     
     
         34 . The release coating composition as claimed in  claim 33  wherein said composition further comprises a wetting agent in an amount constituting about 0.1 to 1.0 wt % of said composition.  
     
     
         35 . The release coating composition as claimed in  claim 33  wherein said wetting agent is selected from the group consisting of fluoroalkyl surfactants, silicone polyether wetting agents, and silicone defoamers.  
     
     
         36 . The release coating composition as claimed in  claim 33  wherein said composition comprises about 10 to 20 wt % of said alkyl vinyl ether monomer, about 60 to 70 wt % of said difunctional acrylate monomer, about 10 to 30 wt % of said trifunctional acrylate monomer and about 3 to 6 wt % of said free-radical initiator.  
     
     
         37 . A method of forming a release coating on a substrate, said method comprising the steps of: 
 (a) coating the substrate with the release coating composition of claim  24 ; and    (b) activating said free-radical initiator until said release coating composition is sufficiently cured so as to form a release coating on the substrate.    
     
     
         38 . The release coating prepared according to  claim 37 .  
     
     
         39 . A method of forming a release coating on a substrate, said method comprising the steps of: 
 (a) coating the substrate with the release coating composition of claim  33 ; and    (b) activating said free-radical initiator until said release coating composition is sufficiently cured so as to form a release coating on the substrate.    
     
     
         40 . The release coating prepared according to  claim 39 .  
     
     
         41 . A method of decorating an article, said method comprising the steps of: 
 (a) providing the heat-transfer label of  claim 1;  and    (b) transferring said transfer portion from said support portion to the article.    
     
     
         42 . The method as claimed in  claim 41  wherein the article is a glass container.  
     
     
         43 . A method of decorating an article, said method comprising the steps of: 
 (a) providing the heat-transfer label of claim  23 ; and    (b) transferring said transfer portion from said support portion to the article.    
     
     
         44 . The method as claimed in  claim 43  wherein the article is a glass container.  
     
     
         45 . A method of decorating a glass article, said method comprising the steps of: 
 (a) providing a heat-transfer label, said heat-transfer label comprising: 
 (i) a transfer portion, said transfer portion comprising 
 (A) an ink design layer, and  
 (B) a heat-activatable adhesive layer over said ink design layer, and  
 
 (ii) a support portion, said transfer portion being positioned over said support portion for transfer, under conditions of heat and pressure, of the transfer portion from the support portion to a glass article, said support portion comprising 
 (A) a carrier, and  
 (B) a release layer positioned over said carrier, said release layer being made of a non-wax, non-silicone, thermoset release material, said release layer separating cleanly from said transfer portion with no visually discernible portion of said release layer being transferred to the glass article along with said transfer portion;  
 
   (b) transferring said transfer portion from said support portion onto the glass article.    
     
     
         46 . The method as claimed in  claim 45  wherein said release layer is in direct contact with said transfer portion.  
     
     
         47 . The method as claimed in  claim 45  wherein said release layer is made by (a) coating onto said carrier a composition comprising (i) a functionalized alkyl monomer having a carbon chain length of at least 18 carbon atoms, (ii) a crosslinking monomer reactive with said functionalized allyl monomer, and (iii) an initiator for effecting at least a partial cure between said functionalized alkyl monomer and said crosslinking monomer and (b) activating said initiator.  
     
     
         48 . The method as claimed in  claim 47  wherein said functionalized alkyl monomer is an alkyl vinyl ether monomer and wherein said crosslinking monomer comprises at least one multifunctional acrylate monomer.  
     
     
         49 . The method as claimed in  claim 45  wherein said release layer is made by (a) coating onto said carrier a composition comprising (i) an alkyl vinyl ether monomer of the formula C n H 2n+1 O—CH═CH wherein n is at least 18, (ii) a trifunctional acrylate monomer, (iii) a difunctional acrylate monomer and (iv) a free-radical initiator and (b) activating said free radical initiator.  
     
     
         50 . The method as claimed in  claim 49  wherein said composition comprises about 5 to 30 wt % of said alkyl vinyl ether monomer, about 40 to 80 wt % of said difunctional acrylate monomer, about 5 to 50 wt % of said trifunctional acrylate monomer and about 2 to 8 wt % of said free-radical initiator.  
     
     
         51 . The method as claimed in  claim 50  wherein said composition further comprises a wetting agent in an amount constituting about 0.1 to 1.0 wt % of said composition.  
     
     
         52 . The method as claimed in  claim 51  wherein said wetting agent is selected from the group consisting of fluoroalkyl surfactants, silicone polyether wetting agents, and silicone defoamers.  
     
     
         53 . The method as claimed in  claim 50  wherein said transfer portion further includes a protective lacquer layer positioned under said ink design layer and wherein said heat-activatable adhesive layer extends beyond the peripheries of said ink design and protective lacquer layers and wherein said release layer is in direct contact with each of said protective lacquer layer and the periphery of said heat-activatable adhesive layer.  
     
     
         54 . The method as claimed in  claim 53  wherein said heat-activatable adhesive layer is a polyester-based adhesive.  
     
     
         55 . A heat-transfer label comprising: 
 (a) a transfer portion, said transfer portion comprising 
 (i) an ink design layer, and  
 (iii) a heat-activatable adhesive layer over said ink design layer; and  
   (b) a support portion, said transfer portion being positioned over said support portion for transfer, under conditions of heat and pressure, of the transfer portion from the support portion to an article, said support portion comprising 
 (i) a carrier, and  
 (ii) a release layer positioned over said carrier, said release layer being made of a non-wax, non-silicone, thermoset release material, said release layer separating cleanly from said transfer portion with no visually discernible portion of said release layer being transferred to the article along with said transfer portion, said release layer being made by (A) coating onto said carrier a composition comprising (1) a functionalized alkyl monomer having a carbon chain length of at least 18 carbon atoms, (2) a crosslinking monomer reactive with said functionalized alkyl monomer, and (3) an initiator for effecting at least a partial cure between said functionalized alkyl monomer and said crosslinking monomer and (B) activating said initiator.  
   
     
     
         56 . The heat-transfer label as claimed in  claim 55  wherein said release layer is in direct contact with said transfer portion.  
     
     
         57 . The heat-transfer label as claimed in  claim 55  wherein said transfer portion further comprises a protective lacquer layer positioned under said ink design layer, said heat-activatable adhesive layer extending beyond the periphery of said protective lacquer layer, said release layer being in direct contact with each of said protective lacquer layer and the periphery of said heat-activatable adhesive layer.  
     
     
         58 . The heat-transfer label as claimed in  claim 55  wherein said functionalized alkyl monomer is an alkyl vinyl ether monomer having a carbon chain length of at least 18 carbon atoms, wherein said crosslinking monomer comprises a mixture of a difunctional acrylate monomer and a trifunctional acrylate monomer and wherein said initiator is a free-radical initiator.  
     
     
         59 . The heat-transfer label as claimed in  claim 58  wherein said composition comprises about 5 to 30 wt % of said alkyl vinyl ether monomer, about 40 to 80 wt % of said difunctional acrylate monomer, about 5 to 50 wt % of said trifunctional acrylate monomer and about 2 to 8 wt % of said free-radical initiator.  
     
     
         60 . The heat-transfer label as claimed in  claim 59  wherein said heat-activatable adhesive layer comprises a polyester resin.  
     
     
         61 . A label comprising: 
 (a) a transfer portion, said transfer portion comprising an ink design layer; and    (b) a support portion, said transfer portion being positioned over said support portion for transfer of the transfer portion from the support portion to an article, said support portion comprising 
 (i) a carrier, and  
 (ii) a release layer positioned over said carrier, said release layer being made of a non-wax, non-silicone, thermoset release material, said release layer separating cleanly from said transfer portion with no visually discernible portion of said release layer being transferred with said transfer portion to an article, said release layer being made by (A) coating onto said carrier a composition comprising (i) a functionalized alkyl monomer having a carbon chain length of at least 18 carbon atoms, (ii) a crosslinking monomer reactive with said functionalized alkyl monomer, and (iii) an initiator for effecting at least a partial cure between said functionalized alkyl monomer and said crosslinking monomer and (B) activating said initiator.  
   
     
     
         62 . The label assembly as claimed in claim  61  wherein said transfer portion further comprises an adhesive layer, said adhesive layer being positioned over said ink design layer.