Two-layer imageable composition including non-volatile acid in bottom layer

Abstract

The present invention provides an imageable composition, which includes a bottom layer including a first strong, non-volatile acid having a pKa of not more than about 8 and coated thereon a top layer including an acid curable composition, an acid generator, an infrared absorber and optionally a colorant. The present invention further provides an imageable element, which includes a substrate and an imageable composition according to the present invention coated on a surface of the substrate. Also provided is method of producing an imaged element according to the present invention.

What is claimed is:  
     
         1 . An imageable composition comprising: 
 a bottom layer comprising a first strong, non-volatile acid having a pKa of not more than about 8; and    coated thereon a top layer comprising an acid curable composition, an acid generator, an infrared absorber and optionally a colorant.    
     
     
         2 . The composition of  claim 1 , wherein said first strong, non-volatile acid has a pKa of not more than about 4.  
     
     
         3 . The composition of  claim 2 , wherein said strong non-volatile acid is a sulfonic acid represented by the formula: 
       R—SO 3 H wherein R is selected from the group consisting of: a substituted or unsubstituted hydrocarbyl of 1 to 22 carbon atoms, a substituted or unsubstituted aryl of 6 to 22 carbon atoms and a mixture thereof.    
     
     
         4 . The composition of  claim 3 , wherein R is selected from the group consisting of: linear, branched or cyclic alkyl of 1 to 22 carbon atom, linear, branched or cyclic haloalkyl of 1 to 22 carbon atom having at least one halogen and a mixture thereof.  
     
     
         5 . The composition of  claim 3 , wherein said sulfonic acid is an aryl sulfonic acid represented by the formula:  
       
         
           
           
               
               
           
         
         wherein each of R 1 , R 2 , R 3 , R 4  and R 5  is independently selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 22 carbon atoms having at least one halogen, aryl of 6 to 12 carbon atoms, halogen, hydroxy, alkoxy, cyano, nitro, alkoxycarbonyl and acyl.  
       
     
     
         6 . The composition of  claim 5 , wherein said acyl is represented by the formula:  
       
         
           
           
               
               
           
         
         wherein R 6  is selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 12 carbon atoms having at least one halogen, alkoxy, cyano, nitro, alkoxycarbonyl and acetyl  
       
     
     
         7 . The composition of  claim 5 , wherein said aryl sulfonic acid is represented by the formula:  
       
         
           
           
               
               
           
         
         wherein each of R 1 , R 4  and R 6  is independently selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 12 carbon atoms having at least one halogen, aryl of 6 to 12 carbon atoms, halogen, hydroxy, alkoxy, cyano, nitro, alkoxycarbonyl and acyl and wherein R 7  is selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 12 carbon atoms having at least one halogen, aryl of 6 to 12 carbon atoms, alkoxycarbonyl and acyl.  
       
     
     
         8 . The composition of  claim 7 , wherein said aryl sulfonic acid is 3-benzoyl-4-hydroxy-6-methoxybenzenesulfonic acid.  
     
     
         9 . The composition of  claim 1 , wherein said acid curable composition comprises: 
 a binder; and    a crosslinking agent for said binder.    
     
     
         10 . The composition of  claim 9 , wherein said binder comprises a polymer having at least two reactive groups each independently selected from the group consisting of: hydroxy, carboxylic acid, amine, carbamate, amide, sulfonamide and imide.  
     
     
         11 . The composition of  claim 10 , wherein said reactive group in said polymer is a hydroxy group.  
     
     
         12 . The composition of  claim 11 , wherein said polymer is selected from the group consisting of: a polyol, a polyether polyol, a novolak resin, a resole resin, a hydroxyfunctional acrylic resin, a hydroxyfunctional polyester resin and combination thereof.  
     
     
         13 . The composition of  claim 9 , wherein said binder is a novolak resin.  
     
     
         14 . The composition of  claim 9 , wherein said crosslinking agent is selected from the group consisting of: a resole resin, an amino resin, an amido resin, an epoxy compound having at least two epoxide groups and a combination thereof.  
     
     
         15 . The composition of  claim 14 , wherein said crosslinking agent is resole resin.  
     
     
         16 . The composition of  claim 14 , wherein said binder is a novolak resin.  
     
     
         17 . The composition of  claim 14 , wherein said crosslinking agent is an amino resin having at least two alkoxymethyl groups.  
     
     
         18 . The composition of  claim 17 , wherein said amino resin is selected from the group consisting of: an alkoxymethylated melamine resin, an alkoxymethylated benzoguanamine resin, an alkoxymethylated glycoluril, an alkoxymethylated polyacrylamid, an alkoxymethylated polymethacrylamid and a combination thereof.  
     
     
         19 . The composition of  claim 18 , wherein said amino resin is an alkoxymethylated melamine resin having from about 2 to about 6 methoxymethyl groups.  
     
     
         20 . The composition of  claim 9 , further comprising an isocyanate crosslinker having at least two isocyanate groups.  
     
     
         21 . The composition of  claim 1 , wherein said bottom layer further comprises a binder selected from the group consisting of: a novolak resin, a resole resin, an amino resin, an epoxy resin, a polyurethane resin, a polyacetal resin and a combination thereof.  
     
     
         22 . The composition of  claim 8 , wherein said acid generator is an ultraviolet, visible or infrared radiation or heat activated compound.  
     
     
         23 . The composition of  claim 22 , wherein said an acid generator is selected from the group consisting of: an onium salt, a covalently bound sulfonate group containing compound, hydrocarbylsulfonamido-N-hydrocarbyl sulfonate and a combination thereof.  
     
     
         24 . The composition of  claim 23 , wherein said acid generator is an onium salt.  
     
     
         25 . The composition of  claim 24 , wherein said onium salt has a non-nucleophilic counter anion selected from the group consisting of: 
 tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, tetrakis(pentafluorophenyl)borate, triflate, pentafluoropropionate, pentafluoroethanesulfonate, benzenesulfonate, p-methylbenzenesulfonate and pentafluorobenzenesulfonate.    
     
     
         26 . The composition of  claim 24 , wherein said onium salt is selected from the group consisting of: an iodonium salt, a sulfonium salt, a hydrocarbyloxysulfonium salt, a hydrocarbyloxyammonium salt, an aryl diazonium salt and a combination thereof.  
     
     
         27 . The composition of  claim 26 , wherein said 
 hydrocarbyloxyammonium salt is a salt of an N-hydrocarbyloxy substituted nitrogen containing heterocyclic compound.    
     
     
         28 . The composition of  claim 27  wherein said N-hydrocarbyloxy substituted nitrogen containing heterocyclic compound is N-ethoxyisoquinolinium hexafluorophosphate.  
     
     
         29 . The composition of  claim 26 , wherein said iodonium salt is 4-octyloxyphenyl phenyliodonium hexafluoroantimonate.  
     
     
         30 . The composition of  claim 26 , wherein said acid generator is a monomeric or oligomeric aromatic diazonium salt.  
     
     
         31 . The composition of  claim 30 , wherein said diazonium salt has a counter anion other than a halide.  
     
     
         32 . The composition of  claim 31 , wherein said counter anion is selected from the group consisting of: sulfate, bisulfate, tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, tetrakis(pentafluorophenyl)borate, triflate, pentafluoropropionate, pentafluoroethanesulfonate, benzenesulfonate, p-methylbenzenesulfonate and pentafluorobenzenesulfonate.  
     
     
         33 . The composition of  claim 30 , wherein said diazonium salt is selected from the group consisting of: 2-methoxy-4-phenylaminobenzene diazonium hexafluorophosphate represented by the formula:  
       
         
           
           
               
               
           
         
         2-methoxy-4-phenylaminobenzenediazonium p-toluenesulfonate represented by the formula:  
         
           
             
             
                 
                 
             
           
         
          an oligomeric diazonium salt selected from the group consisting of compounds represented by the formula:  
         
           
             
             
                 
                 
             
           
         
          wherein n is from 1 to 11; and a combination of any of the aforementioned compounds.  
       
     
     
         34 . The composition of  claim 1 , wherein said acid curable composition further comprises a second strong, non-volatile acid having a pKa of not more than about 8.  
     
     
         35 . The composition of  claim 34 , wherein said second strong, non-volatile acid has a pKa of not more than about 4.  
     
     
         36 . The composition of  claim 35 , wherein said strong non-volatile acid is a sulfonic acid represented by the formula: 
       R-—O 3 H wherein R is selected from the group consisting of: a substituted or unsubstituted hydrocarbyl of 1 to 22 carbon atoms, a substituted or unsubstituted aryl of 6 to 22 carbon atoms and a mixture thereof.    
     
     
         37 . The composition of  claim 36 , wherein R is selected from the group consisting of: linear, branched or cyclic alkyl of 1 to 22 carbon atom, linear, branched or cyclic haloalkyl of 1 to 22 carbon atom having at least one halogen and a mixture thereof.  
     
     
         38 . The composition of  claim 36 , wherein said sulfonic acid is an aryl sulfonic acid represented by the formula:  
       
         
           
           
               
               
           
         
         wherein each of R 1 , R 2 , R 3 , R 4  and R 5  is independently selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 22 carbon atoms having at least one halogen, aryl of 6 to 12 carbon atoms, halogen, hydroxy, alkoxy, cyano, nitro, alkoxycarbonyl and acyl.  
       
     
     
         39 . The composition of  claim 38 , wherein said acyl is represented by the formula:  
       
         
           
           
               
               
           
         
         wherein R 6  is selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 12 carbon atoms having at least one halogen, alkoxy, cyano, nitro, alkoxycarbonyl and acetyl  
       
     
     
         40 . The composition of  claim 38 , wherein said aryl sulfonic acid is represented by the formula:  
       
         
           
           
               
               
           
         
         wherein each of R 1 , R 4  and R 6  is independently selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 12 carbon atoms having at least one halogen, aryl of 6 to 12 carbon atoms, halogen, hydroxy, alkoxy, cyano, nitro, alkoxycarbonyl and acyl and wherein R 7  is selected from the group consisting of: hydrogen, alkyl of 1 to 12 carbon atoms, haloalkyl of 1 to 12 carbon atoms having at least one halogen, aryl of 6 to 12 carbon atoms, alkoxycarbonyl and acyl.  
       
     
     
         41 . The composition of  claim 40 , wherein said aryl sulfonic acid is 3-benzoyl-4-hydroxy-6-methoxybenzenesulfonic acid.  
     
     
         42 . The composition of  claim 34 , wherein said first and said second strong, non-volatile acids are the same.  
     
     
         43 . The composition of  claim 34 , wherein said first and said second strong, non-volatile acids are different acids.  
     
     
         44 . The composition of  claim 1 , further comprising a photothermal converter material.  
     
     
         45 . The composition of  claim 1 , wherein said counter anion of said infrared absorber is the conjugate base of a non-volatile acid.  
     
     
         46 . The composition of  claim 45 , wherein said non-volatile acid has a counter anion other than a halide.  
     
     
         47 . The composition of  claim 46 , wherein said counter anion is selected from the group consisting of: sulfate, bisulfate, tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, tetrakis(pentafluorophenyl)borate, triflate, pentafluoropropionate, pentafluoroethanesulfonate, benzenesulfonate, p-methylbenzenesulfonate and pentafluorobenzenesulfonate.  
     
     
         48 . The composition of  claim 1 , wherein said infrared absorber is selected from the group consisting of: a pigment, a dye and a combination thereof.  
     
     
         49 . The composition of  claim 48 , wherein said infrared absorber is a pigment selected from the group consisting of: black pigments, yellow pigments, orange pigments, brown pigments, red pigments, purple pigments, blue pigments, green pigments, fluorescent pigments, metal powder pigments, polymer bond pigments, insoluble azo pigments, azo lake pigments, condensation azo pigments, chelate azo pigment, phthalocyanine pigments, anthraquinone pigments, perylene pigments, perynone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, colored lake pigments, azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black, Paris Blue, Prussian Blue and a combination thereof.  
     
     
         50 . The composition of  claim 48 , wherein said infrared absorber is a dye selected from the group consisting of: cyanine dyes, squarylium dyes, pyrylium salts and nickel thiolate complexes.  
     
     
         51 . The composition of  claim 1 , wherein said colorant is selected from the group consisting of a colorant dye, a colorant pigment and a combination thereof.  
     
     
         52 . The composition of  claim 1 , wherein said colorant dye is a blue colorant dye represented by the formula:  
       
         
           
           
               
               
           
         
       
     
     
         53 . The composition of  claim 1 , wherein at least one of said infrared absorber and said colorant has a counter anion derived from a non-volatile acid.  
     
     
         54 . An imageable element comprising: 
 a substrate; and    an imageable composition coated on a surface of said substrate, said imageable composition comprising: a bottom layer comprising a first strong, non-volatile acid having a pKa of not more than about 8; and    coated thereon a top layer comprising an acid curable composition, an acid generator, an infrared absorber and optionally a colorant.    
     
     
         55 . The imageable element of  claim 54 , wherein said imageable composition comprises a photothermal converting material.  
     
     
         56 . A method of producing an imaged element comprising the steps of: 
 providing an imageable element comprising a substrate and an imageable composition coated on a surface of said substrate, said imageable composition comprising: a bottom layer comprising a first strong, non-volatile acid having a pKa of not more than about 8, and coated thereon a top layer comprising an acid curable composition, an acid generator, an infrared absorber and optionally a colorant;    imagewise exposing said imageable element to radiation to produce an imagewise exposed element having exposed and unexposed regions;    baking said imagewise exposed element at a temperature and period of time sufficient to produce a cured element; and    contacting said cured element and a developer to remove the unexposed regions and thereby produce said imaged element.    
     
     
         57 . The method of  claim 56 , wherein said exposing step is carried out using an infrared laser.