Patent GB-1066817-A (GB)
Title: Reflector construction
IPC: F21V7/22
Filed: 1964-09-21
Abstract: A reflector construction having a high degree of specularity and a low degree of image distortion comprises in combination (a) a substrate, (b) a coating of polymerized solventless varnish which is a low viscosity, low volatility solventless material that can be polymerized in situ to a hard smooth surface and includes materials occurring as pre-polymers and catalyzed monomers of molecular weight to have a viscosity of at least 10 centipoise at between 60 to 180 DEG C. (c) a reflective layer over the polymerized coating. The construction may comprise (a) a flexible tape having at least one surface of commercial smoothness, wherein the coating (b) covers the smooth surface and has a thickness of 1 to 20 microns and wherein the reflective layer (c) has a thickness of 300 to 1000 Angstroms.  The flexible substrate may be a metal tape e.g. of stainless steel, glass or plastic strip.  The coating of polymerized solventless varnish may consist of a polymerized mixture of a polyhydrogen polysiloxane and an organic compound having a plurality of terminal aliphatic unsaturation sites, examples of which are given; polymerized unsaturated polyester or polymerized unsaturated polyether ester, examples of which are given. The reflective layer may be of chromium, silver, tin or aluminium.  The construction may take the form of a reflective thermoplastic recording tape having an overall thickness of about 50 microns.  The construction may be produced by depositing a thin film of the solventless varnish over the surface of a thin flexible substrate, polymerizing the film of solventless varnish e.g. by heating at 60 to 180 DEG C., depositing e.g. by vapour deposition, a reflective layer on the surface of the polymerized film.  The vapour deposition is effected continuously on the moving strip and the metal coating is stabilized by passing through a chamber containing clean air or oxygen.ALSO:A reflector construction having a high degree of specularity and a low degree of image distortion comprises in combination (a) a substrate, (b) a coating of polymerized solventless varnish which is a low viscosity, low volatility solventless material that can be polymerized in situ to a hard smooth surface and includes materials occurring as pre-polymers and catalyzed monomers of molecular weight to have a viscosity of at least 10 centipoise at between 60 to 180 DEG C (c) a reflective layer over the polymerized coating.  The construction may comprise (a) a flexible tape having at least one surface of commercial smoothness, wherein the coating (b) covers the smooth surface and has a thickness of 1 to 20 microns and wherein the reflective layer (c) has a thickness of 300 to 1000 Angstroms.  The flexible substrate may be a metal tape e.g. of stainless steel, glass or plastic strip.  A layer of solvent resistant organic polymer may cover and seal the reflective layer.  A layer of thermoplastic polymer may be provided over the reflective layer and/or the sealing layer.  The coating of polymerized solventless varnish may consist of a polymerized mixture of a polyhydrogen polysilozane and an organic compound having a plurality of terminal aliphatic unsaturation sites, examples of which are given; polymerized unsaturated polyester or polymerized unsaturated polyether ester, examples of which are given.  The reflective layer may be of chromium, silver, tin or aluminium.  The layer of solvent resistant polymer may consist of a layer of chromated vinyl alcohol polymer having a thickness of about 0.2 microns, polydiphenyl silozane, or a phenol-formaldehyde resin dissolved in butyl cellulose.  The construction may take the form of a reflective thermoplastic recording tape having an overall thickness of about 50 microns. The construction may be produced by depositing a thin film of the solventless varnish over the surface of a thin flexible substrate, polymerizing the film of solventless varnish e.g. by heating at 60 to 180 DEG C, depositing e.g. by vapour deposition, a reflective layer on the surface of the polymerized film and applying a thin layer of thermoplastic polymer over the reflective layer.