| 摘要 |
Capped connected branch copolymers are provided comprising a core segment, branched polymer segments attached to the core segment, linear polymer segments attached to the terminals of the branched polymer segments, and cap segments, which comprise residues of an alkylene oxide containing at least 4 carbon atoms and which are attached to the free terminals of the linear polymer segments. These capped copolymers are less water-soluble than the uncapped connected branched copolymers from which they are derived, and are useful in carbonless copying systems as carriers for the color precursor microcapsules. The microcapsules can be applied to the carbonless copying sheet by dispersing the microcapsules in the capped copolymer, heating the copolymer above its transition temperature and spreading the melted copolymer over the sheet. After cooling, the copolymer forms a coherent layer on the sheet. Since no water is required for application of the copolymer, the curling and wrinkling problems encountered when using aqueous dispersions of the microcapsules are avoided.
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