| 摘要 |
PURPOSE:To obtain a binder for thermal recording which can be used with a high-speed printer or the like, by using an aqueous solution of a water-soluble copolymer of acrylic amide and/or methacrylic amide with N-vinylpyrrolidone in which the comonomer ratio by weight is specified. CONSTITUTION:The binder consists of an aqueous solution of a water-soluble copolymer comprising 50-80wt% of acrylic amide and/or methacrylic amide and 20-50wt% of N-vinylpyrrolidone. If the total amount of acrylic amide and/or methacrylic amide is less than 50wt%, color forming property of the thermal recording paper produced is poor, whereas if the amount is more than 80wt%, the effect on prevention of ground color development or ground fogging is lowered. The monomeric mixture is diluted with water so that the total concentration of the monomers (acrylic amide and/or methacrylic amide and N-vinylpyrrolidone) is 10-35wt%, a polymerization initiator is added to the diluted liquid, and the resultant mixture is brought into reaction for 0.5-3hr at a temperature of 60-90 deg.C in a nitrogen atmosphere. |
