Visor and method of manufacture

Abstract

A visor for a helmet or the like has a curved, transparent shield with an inner surface and an outer surface. The shield is provided with attachment elements for connecting the visor to the helmet and further includes a viewing region having a photochromatic insert at its outer surface, capable of responding to incident light. The shield is formed of a first plastic material provided with an amount of UV stabilizing additives, the UV stabilizing additives protecting the first plastic material from degradation by UV radiation during use, and the insert includes a second plastic material without UV stabilizing additives or having substantially less UV stabilizing additives than the first plastic material. A manufacturing process for producing a visor with a functional insert region is also disclosed.

1 . A visor for a helmet or the like, comprising a curved, transparent shield having an inner surface and an outer surface, the shield being provided with attachment elements for connecting the visor to the helmet and further comprising a viewing region, the viewing region being provided with a photochromatic insert at its outer surface, capable of responding to incident light, wherein the shield is formed of a first plastic material provided with an amount of UV stabilizing additives, the UV stabilizing additives protecting the first plastic material from degradation by UV radiation during use, and wherein the insert comprises a second plastic material without UV stabilizing additives or having substantially less UV stabilizing additives than the first plastic material. 
     
     
         2 . The visor according to  claim 1 , wherein the second plastic material is substantially free of stabilizing additives that operate in the 315 nm to 400 nm range. 
     
     
         3 . The visor according to  claim 1 , wherein the first and second plastic materials are the same. 
     
     
         4 . The visor according to  claim 1 , wherein the first plastic material comprises polycarbonate. 
     
     
         5 . The visor according to  claim 1 , wherein the insert is removably attached to the outer surface of the shield. 
     
     
         6 . The visor according to  claim 1 , wherein the insert and the shield are integrally injection moulded together. 
     
     
         7 . The visor according to  claim 1 , wherein the insert has a thickness of between 0.3 mm and 0.7 mm, preferably around 0.5 mm. 
     
     
         8 . The visor according to  claim 1 , wherein the insert comprises a photochromatic layer between an inner and an outer protective layer, at least the outer protective layer comprising the second plastic material. 
     
     
         9 . The visor according to  claim 8 , wherein the photochromatic layer comprises a photochromatic pigment incorporated in a polymer having a relatively low molecular density compared to that of the first plastic material. 
     
     
         10 . A method of manufacturing a visor for a helmet or the like having a functional insert region, the method comprising:
 providing insert material having the desired functionality;   thermoforming the insert material into a curved shape to form an insert;   locating the insert within a mould;   injection moulding visor material into the mould to form a curved visor having an inner surface and an outer surface, wherein the insert forms a portion of the outer surface.   
     
     
         11 . The method according to  claim 10 , wherein the insert material comprises an extruded film. 
     
     
         12 . The method according to  claim 10 , wherein the insert material comprises an optical quality surface prior to location within the mould. 
     
     
         13 . The method according to  claim 10 , wherein the insert material comprises a multilayer laminate. 
     
     
         14 . The method according to  claim 10 , wherein the insert comprises a photochromatic layer. 
     
     
         15 . The method according to  claim 10 , wherein the visor material comprises UV stabilising additives and the insert material comprises relatively less of the UV stabilising additives than the visor material. 
     
     
         16 . The method according to  claim 10 , wherein the functional insert region comprises a viewing region of the visor. 
     
     
         17 . The method according to  claim 10 , wherein the functional insert region is visibly different from the remainder of the visor and has a distinctive shape. 
     
     
         18 . The method according to  claim 10 , wherein the mould has a cavity and a surface of the cavity corresponding to the outer surface of the visor has a non-optical quality finish. 
     
     
         19 . The method according to  claim 10 , wherein the insert is maintained below 150° C. during injection moulding of the visor material. 
     
     
         20 . The method according to  claim 10 , wherein the mould has a cavity and a surface of the cavity corresponding to the outer surface of the visor comprises a recess having a shape approximating the shape of the insert.