Copy paper
OwnerJoachim Schmidt, Martin Unruhinventors
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Abstract
A sheet of paper suitable as a multi-copy paper or once only copy paper is made by coating with a layer of finely particulate mutually adherent particles of a vinyl chloride polymer if pigments are used as colouring matter and of any swellable polymer if a dyed layer is to be used. Generally, the particulate material is swelled using suitable swelling agents and applied to a support layer by any suitable coating process.
Claims4
A sheet of paper consisting of a support layer and a substantially uniform donor layer of particulate mutually adherent particles of a vinyl chloride polymer, the polymer having been produced by emulsion polymerization, containing from 0.1 - 4% by weight of an emulsifier and having a K-value in the range from 60 to 80, the particles having an average size of 50 .mu. or less and having sieve residues under standard DIN conditions of not more than 34% by weight, and said polymer having been dyed by a dye selected from the group consisting of anionic dyes, non-ionic dyes and mixtures thereof prior to incorporation onto said sheet of paper.
Dependencies are inferred from the claim text.