| 摘要 |
1,271,289. Pressure-sensitive copying papers. WIGGINS TEAPE RESEARCH & DEVELOPMENT Ltd. 21 Aug., 1970 [4 Sept., 1969], No. 43912/69. Heading D2B. [Also in Division C4] Reduced hydrophilic complex heterocyclic dyes containing at least one N-acylated reduced azine or oxazine ring system as part of the chromophone, the nitrogen atom being a tertiary nitrogen atom are used as colour formers for copying papers. The colour formers may be used in transfer systems and may be encapsulated within polymeric shells, optionally with plasticisers to promote transfer to receiving sheets. |
