HEAT-SENSITIVE RECORDING MATERIAL

摘要

1530353 Heat-sensitive recording material CIBAGEIGY AG 26 Feb 1976 [27 Feb 1975 8 Aug 1975] 07681/76 Heading G2C A heat-sensitive recording material contains as colour former at least one azo compound of Formula wherein D represents a phenyl radical which is optionally substituted by halogen, alkyl, alkoxy, aryloxy, alkoxycarbonyl, N, N, N-dialkylaminocarbonyl, acylamino, N-acyl-N-alkylamino or the group -SO 2 -N#Y 1 #Y 2 wherein each of Y 1 and Y 2 independently represent alkyl or aryl or, together with the nitrogen atom to which they are attached, represent a heterocyclic ring which optionally contains an oxygen atom, X 1 represents hydrogen or alkyl, X 2 represents alkyl, cyanoalkyl, or arylmethyl, or X 1 and X 2 , together with the nitrogen atom to which they are attached, represent a heterocyclic ring which optionally contains an oxygen atom, X 3 represents alkyl or aryl, and n is 1 or 2. The notation denotes a phenylene or naphthylene group. When the colour formers are contacted with an acid developer they give orange to blue and grey shades. Both the colour former and the acid developer may be dispersed in a water soluble binder and coated in one layer on a carrier. Alternatively the colour former is dispersed or dissolved in one binder layer and the developer is dispersed or dissolved in the binder in a second layer, in which case the binder can be water insoluble. On the application of heat the binder softens or melts so that the colour former comes into contact with the developer in the heated areas and a colour forms immediately. In Example 1 the coated sheet is laid coated face down on an untreated paper surface. Using a heated pen, markings are applied to the upper side of the two sheet-system and these are transferred to the bottom sheet. In Example 7 a sheet A is coated with a developer dispersed in a binder and a sheet B is coated with a colour former dispersed in a second binder. Sheets A and B are laid coated faces in contact and markings made by mechanical means on sheet B. Upon IR irradiation a copy of the marking on sheet B is obtained on sheet A. The coatings may also contain talc, TiO 2 , ZnO or CaCO 3 or organic pigments such as urea/formaldehyde polymers to improve the degree of whiteness, facilitating the printing of papers, and for preventing the heated pen from sticking. Urea, thiourea, acetanilide, phthalic anhydride may be added to induce the simultaneous melting of the colour former and developer.