Record material for pressure and heat development - having colour developer contg. hydrated zirconia and hydrated silica and/or hydrated alumina

摘要

Record material has a colour developer compsn. comprising a particulate composite of hydrated ZrO2 with hydrated SiO2 and/or Al2O3. The proportion of hydrated ZrO2 is at least 10 wt.% (on a dry wt. basis) based on the total dry wt. of ZrO2, SiO2, and Al2O3. The amt. of SiO2 is greater than Al2O3. Also claimed is the colour developer itself, a process for the prodn. of the developer comprising synthesising the composite in an aq. medium and a process for the prodn. of the record material comprising forming an aq. dispersion of the developer and either formulating it into a coating compsn. and applying this to a substrate web, or introducing the dispersion into papermaking stock and forming a paper web; and finally drying the coated or loaded web. This material is useful in heat- and pressure-sensitive recording systems. The colours developed are of a good intensity and show good fading resistance.