Patent ID: 6291027
Filing Date: 2001-09-18
Classification: B05D,F26B

Abstract:
A process for coating a metal substrate, comprising the steps of:(a) applying a liquid organic, polymeric basecoating composition to a surface of the metal substrate;(b) exposing the basecoating composition to air having a temperature ranging from about 10.degree. C. to about 35.degree. C. for a period of at least about 30 seconds to volatilize at least a portion of volatile material from the liquid basecoating composition, the velocity of the air at a surface of the basecoating composition being about 0.3 to about 0.5 meters per second;(c) applying infrared radiation at a power density of about 25 kilowatts per square meter or less and warm air simultaneously to the basecoating composition for a period of at least about 30 seconds, the velocity of the air at the surface of the basecoating composition being about 0.3 to about 4 meters per second, the temperature of the metal substrate being increased at a rate ranging from about 0.02.degree. C. per second to about 0.4.degree. C. per second to achieve a peak metal temperature of the substrate ranging from about 20.degree. C. to about 60.degree. C.;(d) applying infrared radiation and hot air simultaneously to the basecoating composition for a period of at least about 30 seconds, the velocity of the air at the surface of the basecoating composition being less than about 4 meters per second, the temperature of the metal substrate being increased at a rate ranging from about 0.4.degree. C. per second to about 1.5.degree. C. per second to achieve a peak metal temperature of the substrate ranging from about 40.degree. C. to about 75.degree. C., such that a dried basecoat is formed upon the surface of the metal substrate; and(e) applying a liquid topcoating composition over the dried basecoat.