| 摘要 |
1,185,708. Reflective markers. PRISMO SAFETY CORP. 28 March, 1967 [2 Dec., 1966], No. 14091/67. Heading B2K. [Also in Division G2] A constant thickness transparent top coating is applied to the surface of an exposed lens type marker by air spraying onto the surface of said marker, a composition comprising 0.25-20% by weight of resin together with 80-99.75% by weight of solvent the solvent having an effective relative evaporation rate of between 43 and 100 based on the evaporation rate of butyl acetate being 100, said air spray being conducted at an air to fluid ratio of 1.2-1.3 cu, ft./sq. ft. of sign surface to 0.6-0.8 oz. of fluid/sq. ft. of sign surface at a temperature of 70-95‹F and a relative humidity greater than 20% so as to obtain an average dry thickness of top coating of not greater than 0.2 mils. Resins specified are alkyd resins, acrylic esters, polyvinyl chloride, polyvinyl chloride-acetate copolymers, cellulose acetate butyrate, alkyd-melamine, polysiloxane, urea-formaldehyde and melamineformaldehyde. Numerous suitable solvents are specified and mixtures may be employed e.g. of a fast solvent with a relative evaporation rate greater than 100 with a slow solvent which has a relative evaporation rate less than 43. A message in transparent colour may be screen printed on to the marker before application of the top coat and at least some of the glass spheres may be coated with a reflective metal layer. The backing may be of wood or metal. |
