- Email: [email protected]
Lead chromate pigments and health
Uol
COLOUR MATCHING
17,
No.
4, Page 3
The numerical calculation of colour perception is a complex and lengthy process, and its industrial application only became feasible with the development of the analogue computer. Instrumental Colour Systems in the U.K. and Applied Colour Systems in the U.S. have developed a complete colour system which allows pigment formulations to be produced by computer in a few seconds. Colour is perceived via green, blue and red receptors in the eye. All colours are therefore a mix of three basics. In order to create programmes for colour matching, it is necessary to consider not anly the reflected and absorbed light from an object but also the way the eye perceives these. The Instrumental Colour Systems equipment uses a Macbeth reflectance spectraphotometer linked to a digital computer. The spectrophotometer measures colour reflectance under different lighting conditions: daylight, tungsten, cool white, fluorescent, and store display. The computer then analyses the colour mathematically and calculates several formulations for reproducing the required shade using available pigments, For each proposed formulation, the computer will show colour match under the four lighting conditions and the cost of producing that blend of pigments. ICS systems are used in a wide variety of industries including textiles, food, pharmaceuticals, paints and plastics. For plastics masterbatch manufacture, only two sets of data have been found necessary to cover the most diverse range of base polymers and compounds, Plast. Rubb. Int., 1987,
COLOUR SENSING
12,
(Feb.),
10
A range of equipment for control and measurement of colour is produced by Macbeth Division of Kollmorgen (U.K.) Ltd. which can sense colour at a distance of 2-5 metres? allowing measurement in hazardous or high temperature areas such as curing ovens, etc, This equipment will measure colour of products which are non-homogeneous, large area, contain pattern effects or are in a harsh environment unsuited to the traditional spectrocolorimeter. Plast_ Rubb. Int., 1987, -12, (Feb.), 10
LEAD CHROMATE FIGMENTS AND HEALTH
A recent study in the U.S, undertaken by Heubach has concluded that lead chromate-based pigments are non-carcinogenic, Plast. Tech., 1986, 32, (Oct.), 139-141
ADDlTlVES FOR POLYMERS
No part of this publication may be reproduced. stored in a retrieval system. or transmitted by any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the priar permission of the publishers. [Readers in the U.S.A. - please see special regulations listed on back cover.)
COLOUR MATCHING
17,
No.
4, Page 3
The numerical calculation of colour perception is a complex and lengthy process, and its industrial application only became feasible with the development of the analogue computer. Instrumental Colour Systems in the U.K. and Applied Colour Systems in the U.S. have developed a complete colour system which allows pigment formulations to be produced by computer in a few seconds. Colour is perceived via green, blue and red receptors in the eye. All colours are therefore a mix of three basics. In order to create programmes for colour matching, it is necessary to consider not anly the reflected and absorbed light from an object but also the way the eye perceives these. The Instrumental Colour Systems equipment uses a Macbeth reflectance spectraphotometer linked to a digital computer. The spectrophotometer measures colour reflectance under different lighting conditions: daylight, tungsten, cool white, fluorescent, and store display. The computer then analyses the colour mathematically and calculates several formulations for reproducing the required shade using available pigments, For each proposed formulation, the computer will show colour match under the four lighting conditions and the cost of producing that blend of pigments. ICS systems are used in a wide variety of industries including textiles, food, pharmaceuticals, paints and plastics. For plastics masterbatch manufacture, only two sets of data have been found necessary to cover the most diverse range of base polymers and compounds, Plast. Rubb. Int., 1987,
COLOUR SENSING
12,
(Feb.),
10
A range of equipment for control and measurement of colour is produced by Macbeth Division of Kollmorgen (U.K.) Ltd. which can sense colour at a distance of 2-5 metres? allowing measurement in hazardous or high temperature areas such as curing ovens, etc, This equipment will measure colour of products which are non-homogeneous, large area, contain pattern effects or are in a harsh environment unsuited to the traditional spectrocolorimeter. Plast_ Rubb. Int., 1987, -12, (Feb.), 10
LEAD CHROMATE FIGMENTS AND HEALTH
A recent study in the U.S, undertaken by Heubach has concluded that lead chromate-based pigments are non-carcinogenic, Plast. Tech., 1986, 32, (Oct.), 139-141
ADDlTlVES FOR POLYMERS
No part of this publication may be reproduced. stored in a retrieval system. or transmitted by any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the priar permission of the publishers. [Readers in the U.S.A. - please see special regulations listed on back cover.)