摘要 |
The present invention relates to a sheet-form or web-form copying material having an improved shelf life. More particularly, the invention relates to that part of copying materials of the type in question which contains the dye precursor by providing a new type of binder which may be used in conjunction with a variety of known dye precursors. Applied to the support material, it forms a unit of the pressure-sensitive copying material which, in combination with a plurality of known units containing dye acceptor material, forms pressure-sensitive copying material according to the invention. |