Patent · US Expired

Recording material containing asbestos

US4131710A · kind A · utility

1Cited by

9References

10Claims

0Family size

Assignee

Feldmuhle Aktiengesellschaft · DE

Inventors

Guido Dessauer · Tutzing, DE
Kurt Ramlow · Schafflund, DE
Kurt Riecke · Kempen, DE
Franz Wirnitzer · Flensburg, DE

Key dates

Filing date	Jan 18, 1977
Grant date	Dec 26, 1978
Priority date	—
Expiry date	Jan 18, 1997

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/26
WIPO fieldTextile and paper machines
WIPO sectorMechanical engineering

Abstract

A recording sheet consisting mainly of fibrous material is capable of displaying a colored image when contacted under pressure with substantially colorless crystal violet lactone and similar dye precursors if at least 3% of the fibrous material is constituted by uniformly distributed asbestos fibers. Sheets having adequate strength for carbonless copying should not contain more than 30% asbestos fibers. Stronger colors are obtained if the sheet further contains a mixture of .gamma.-alumina and .gamma.-alumina precursors in an amount of 2% to 20% of the weight of the fibrous material, the mixture containing 1% to 30% water volatile at 1000.degree. C, and being converted substantially entirely to .gamma.-alumina when heated from 300.degree. to 1000.degree. C.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.