| 摘要 |
1,222,035. Pressure-sensitive record sheets. NATIONAL CASH REGISTER CO. 1 July, 1969 [11 July, 1968], No. 33189/69. Heading D2B. In a pressure-sensitive record material comprising a sheet carrying pressure-rupturable microcapsules of two kinds, are containing a solution of chromogenic material and the other a solution of an acidic material that will react with the chromogenic material to produce a coloured dyestuff when their solutions are mixed, capsules of both kinds have walls of hyrophilic polymeric materials, but those containing the acid also have within the interstices of the capsule wall material solid hydrophoblic polymeric material produced by a condensation polymerisation between two monomeric reactants in situ. Preferably, the acidic material is a solution of an oil-soluble phenolic polymer, the hydrophilic wall material of the capsules containing it is polyvinyl alcohol and the condensation polymer is formed from resorcinol and formaldehyde, by the method of Specification 1,190,721. |
