Contoured face shields and method of producing optically clear parts

Abstract

A face shield comprising a contoured visor with three-dimensional structures with varying angles along multiple axes for improved protection and user comfort, an adjustable attachment member for easy user adjustment, and head contact area with improved ventilation. Methods of producing optically clear three-dimensional plastic structures with varying angles along multiple axes and tools for said method.

What is claimed is: 
     
         1 . A face shield comprising:
 (a) a contoured visor having a 3-dimensional shape portion with varying angles along multiple axes that protects a user's face from the front, bottom and sides, thereby achieving improved operational safety and user comfort, while retaining optical clarity, and   (b) a head contact member.   
     
     
         2 . The face shield of  claim 1 , wherein said face shield is made of a material comprising hypoallergenic and latex free materials. 
     
     
         3 . The face shield of  claim 1 , wherein said head contact area comprises a 3-dimensional protrusion created by deforming said visor to create a tripod protrusion. 
     
     
         4 . The face shield of  claim 1 , wherein said head contact area comprises a cushion member connected to said visor by an attachment member. 
     
     
         5 . The face shield of  claim 1 , wherein said face shield further comprises an adjustable attachment member that allows easy visor angle and position adjustment by the user. 
     
     
         6 . The face shield of  claim 5 , wherein said adjustable attachment member comprises a single elastic head strap. 
     
     
         7 . The face shield of  claim 6 , wherein said single elastic head strap further comprises a fastener or coupling member for strap length adjustment. 
     
     
         8 . The face shield of  claim 5 , wherein said adjustable attachment member comprises two head straps with fasteners or coupling members for strap length adjustment. 
     
     
         9 . The face shield of  claim 5 , wherein said adjustable attachment member comprises an adjustable ratchet headgear. 
     
     
         10 . The face shield of  claim 1 , wherein said visor has two axes points, horizontal and vertical, to achieve improved coverage and protection. 
     
     
         11 . The face shield of  claim 10 , wherein said visor comprises a smooth contour shape with a substantially uniform curvature angle. 
     
     
         12 . The face shield of  claim 10 , wherein said visor comprises a varying contour angle for optimum coverage and fitting. 
     
     
         13 . The face shield of  claim 12 , wherein said visor comprises a steeper contour angle of two axes points near the chin portion for protective coverage, while the center portion is substantially flat, and side portions which are only minimally contoured in two axes points. 
     
     
         14 . The face shield of  claim 1 , wherein said visor comprises of thin plastic material with improved optical clarity and light weight compared to conventional face shields. 
     
     
         15 . The face shield as claimed in any of the preceding claims, wherein said visor further comprises a single or multiple coatings on the surface, selected from the group comprising of scratch resistant coating, tint coating, anti-fog coating, anti-glare coating, anti-reflection coating, stain-proof coating, and UV light filtering or blocking coating. 
     
     
         16 . A single piece face shield comprising:
 (a) a visor having a 3-dimensional feature with varying angles along multiple axes that provides protection from the sides as well as the bottom of a user's head, significantly enhancing operational safety and user comfort,   (b) a visor geometry based on flexibility in plastic material forming said visor to allowing the visor to conform to various users' head shapes, while utilizing the strength of the visor's plastic material to provide adequate structure as the visor is kept sufficiently off the users' head,   (c) a head contact area for improved ventilation, and   (d) an adjustable attachment member securing the visor to the user's head that allows easy visor angle and position adjustment by the user.   
     
     
         17 . The face shield of  claim 16 , wherein said face shield comprises hypoallergenic and latex free materials. 
     
     
         18 . The face shield of  claim 16 , wherein said head contact area comprises a 3-dimensional protrusion created by deforming said visor to create a tripod protrusion. 
     
     
         19 . The face shield of  claim 16 , wherein said head contact area comprises a tripod cushion member connected to said visor by an attachment member. 
     
     
         20 . The face shield of  claim 16 , wherein said adjustable attachment member comprises a single elastic head strap. 
     
     
         21 . The face shield of  claim 20 , wherein said single elastic head strap further comprises a fastener or coupling member for strap length adjustment. 
     
     
         22 . The face shield of  claim 16 , wherein said adjustable attachment member comprises a single non-elastic head strap with a fastener or coupling member for strap length adjustment. 
     
     
         23 . The face shield of  claim 16 , wherein said adjustable attachment member comprises two elastic head straps with fasteners or coupling members for strap length adjustment. 
     
     
         24 . The face shield of  claim 16 , wherein said adjustable attachment member comprises an adjustable ratchet headgear. 
     
     
         25 . The face shield of  claim 16 , wherein said visor has two axes points, horizontal and vertical, to achieve improved coverage and protection. 
     
     
         26 . The face shield of  claim 25 , wherein said visor comprises a smooth contour shape with a substantially uniform curvature angle. 
     
     
         27 . The face shield of  claim 25 , wherein said visor comprises a varying contour angles for optimum coverage and fitting. 
     
     
         28 . The face shield of  claim 27 , wherein said visor comprises steeper contour angle of two axes points near the chin portion for protective coverage, while the center portion and side portion are only minimally contoured in two axes points. 
     
     
         29 . The face shield of  claim 16 , wherein said visor comprises of thin plastic material with excellent optical clarity and light weight. 
     
     
         30 . The face shield as claimed in any one of  claims 16  to  29 , wherein said visor further comprises a single or multiple coatings on the surface, selected from the group comprising scratch resistant coating, tint coating, anti-fog coating, anti-glare coating, anti-reflection coating, stain-proof coating, and UV light filtering or blocking coating. 
     
     
         31 . A method of producing a 3-dimensional plastic part with varying angles along multiple axes and improved optical clarity, comprising:
 (a) thermoforming by heating a plastic film to its forming temperature only in areas where 3-dimensional formed geometry is desired and not heating portions of said plastic film that are desired to retain optical clarity,   (b) forming said selectively heated plastic film into the desired shape using a mould, and   (c) cooling said plastic film in the mould to harden said film to its desired shape.   
     
     
         32 . The method of  claim 31 , wherein said method comprises the use of one or more heat masking elements. 
     
     
         33 . The method of  claim 31  or  32 , wherein said method comprises:
 (i) vacuum-forming, wherein said sheet of plastic film is located adjacent to a heating element to heat up to the forming temperature of the plastic film, while the heat mask is employed on portions desired to retain optical clarity, 
 (ii) followed by said heated film being draped over a shaped mould, wherein said shaped mould incorporates a vacuum, drawing the flexible plastic sheet down onto the mould, and 
 (iii) cooling said plastic film in the mould to harden to its desired shape. 
 
     
     
         34 . The method of  claim 32 , wherein said method comprises:
 (i) pressure-forming, wherein said sheet of plastic film is brought into contact with a “hot plate”, whereupon the plastic film rises to its forming temperature, while said one or more heat masking elements are employed on portions desired to retain optical clarity,   (ii) followed by air blown to pressurize the film and press it against a mould positioned directly in line with the plastic film, and   (iii) cooling said plastic film in the mould to harden to its desired shape.   
     
     
         35 . The method of  claim 34 , wherein said air blowing is carried out through perforations in the hot plate. 
     
     
         36 . The method of  claim 32 ,  33 , or  34 , wherein one or more of said heat masking elements comprises applying insulation material directly onto the hot plate, using attachment members. 
     
     
         37 . The method of  claim 34 , wherein one or more of said heat masking elements comprises a customized hotplate, wherein there is an insulator embedded directly into the hot plate surface, shaped to an exact area of desired optical clarity. 
     
     
         38 . The method of  claim 34 , wherein one or more of said heat masking elements is made from the same piece of material as the hot-plate. 
     
     
         39 . The method of  claim 38 , wherein the hot plate is aluminum based, wherein the heat masked area comprises aluminum that is not in contact with the overall heating elements, thereby creating cooler portions of the hot-plate. 
     
     
         40 . The method as claimed in any one of  claims 31  to  39 , wherein one or more of said heat masking elements is a passive heat mask. 
     
     
         41 . The method of  claim 40 , wherein said passive heat mask is selected from a group comprising cooling by ambient air, air flow from the pressurizing or vacuuming to push or pull the plastic film into the mould, by the heat-draw of the plastic film itself, or regulated temperature by controlling the material thickness in the heat-mask portion. 
     
     
         42 . The method as claimed in any one of  claims 31  to  39 , wherein one or more of said heat masking elements is an active heat mask. 
     
     
         43 . The method of  claim 42 , wherein said active heat mask is selected from a group comprising water-cooling, air-cooling, solid-state cooling, and fans. 
     
     
         44 . The method as claimed in any one of  claims 31  to  43 , wherein the insulation materials is selected from a group comprising of insulating ceramic, mineral fiber, tool-makers insulation board, Teflon, and DME thermal insulation sheet. 
     
     
         45 . The method as claimed in any one of  claims 31  to  44 , wherein the method produces the face shield of  claim 1  through  30 . 
     
     
         46 . A method of producing the face shield as claimed in any one of  claim 1  to  30 , comprising:
 (a) thermoforming by heating a plastic film to its forming temperature only in areas where 3-dimensional formed geometry is desired and not heating portions of said plastic film that are desired to retain optical clarity, 
 (b) forming said selectively heated plastic film into the desired shape using a mould, and 
 (c) cooling said plastic film in the mould to harden to its desired shape. 
 
     
     
         47 . The method of  claim 46 , wherein said method comprises the use of one or more heat masking elements. 
     
     
         48 . The method of  claim 46 , wherein said method further comprises:
 (i) vacuum-forming, wherein said sheet of plastic film is located adjacent to a heating element to heat up to the forming temperature of the plastic film, while one or more said heat masking elements are employed on portions desired to retain optical clarity,   (ii) followed by said heated film being draped over a shaped mould, wherein said shaped mould incorporates a vacuum, drawing the flexible plastic sheet down onto the mould, and   (iii) cooling said plastic film in the mould to harden to its desired shape.   
     
     
         49 . The method of  claim 47 , wherein said method comprises:
 (i) pressure-forming, wherein said sheet of plastic film is brought into contact with a “hot plate”, whereupon the plastic film rises to its forming temperature, while one or more said heat masking elements is employed on portions desired to retain optical clarity,   (ii) followed by air blown to pressurize the film and press it against a mould positioned directly in line with the plastic film, and   (iii) cooling said plastic film in the mould to harden to its desired shape.   
     
     
         50 . The method of  claim 49 , wherein said air blowing is carried out through perforations in the hot plate. 
     
     
         51 . The method of  claim 48 ,  49 , or  50 , wherein one or more of said heat masking elements comprises applying insulation material directly onto the hot plate, using any number of attachment member. 
     
     
         52 . The method of  claim 49 , wherein one or more of said heat masking elements comprises a customized hotplate, wherein there is an insulator embedded directly into the hot plate surface, shaped to the exact area of desired optical clarity. 
     
     
         53 . The method of  claim 49 , wherein one or more of said heat masking elements is made from the same piece of material as the hot-plate. 
     
     
         54 . The method of  claim 53 , wherein the hot plate is aluminum or steel based, wherein the heat masked area comprises aluminum or steel that is not in contact with the overall heating elements, thereby creating cooler portions of the hot-plate. 
     
     
         55 . The method as claimed in any one of  claims 47  to  54 , wherein on or more of said heat masking element is a passive heat mask. 
     
     
         56 . The method of  claim 55 , wherein said passive heat mask is selected from a group comprising cooling by ambient air, air flow from the pressurizing or vacuuming to push or pull the plastic film into the mould, by the heat-draw of the plastic film itself, or regulated temperature by controlling the material thickness in the heat-mask portion. 
     
     
         57 . The method as claimed in any one of  claims 47  to  54 , wherein one or more of said heat masking element is an active heat mask. 
     
     
         58 . The method of  claim 57 , wherein said active heat mask is selected from a group comprising water-cooling, air-cooling, solid-state cooling, and fans. 
     
     
         59 . The method as claimed in any one of  claims 47  to  58 , wherein the insulation materials is selected from a group comprising of insulating ceramic, mineral fiber, tool-makers insulation board, Teflon, and DME thermal insulation sheet. 
     
     
         60 . An apparatus for pressure forming a plastic film comprising:
 (a) a mould of the desired shape connected to a cavity plate,   (b) a cutting die bottom surrounding the mould and connected to said cavity plate,   (c) said cavity plate connected to a larger mounting plate through slots, thereby allowing each cavity position adjustment in one axis,   (d) a hotplate with embedded cutting and embedded insulation surface, connected to hot plate.   
     
     
         61 . The apparatus of  claim 60 , further comprising air outlets. 
     
     
         62 . The apparatus of  claim 61 , wherein said air outlets are positioned on said embedded insulation surface to provide further cooling of the insulation surface. 
     
     
         63 . The apparatus of  claim 60 ,  61 , or  62 , wherein said embedded insulation surface comprises insulation material selected from a group comprising of insulating ceramic, mineral fiber, tool-makers insulation board, Teflon, and DME thermal insulation sheet. 
     
     
         64 . An apparatus for pressure forming a plastic film comprising:
 (a) a mould of the desired shape bottom connected to a cavity plate,   (b) a cutting die bottom surrounding the mould and connected to said cavity plate,   (c) said cavity plate connected to a larger mounting plate through slots, thereby allowing each cavity position adjustment in one axis,   (d) a hotplate with embedded cutting and insulation material directly covering the hotplate surface by an attachment member, connected to hot plate.   
     
     
         65 . The apparatus of  claim 64 , further comprising air outlets. 
     
     
         66 . The apparatus of  claim 64  or  65 , wherein said insulation material is selected from a group comprising of insulating ceramic, mineral fiber, tool-makers insulation board, Teflon, and DME thermal insulation sheet. 
     
     
         67 . The apparatus as claimed in any one of  claims 60  to  66 , further comprising a passive cooling member. 
     
     
         68 . The apparatus of  claim 67 , wherein the passive cooling member is selected from a group comprising an air compressor and air outlet, a vacuum pump and vacuum port, and controlling the material thickness in the heat-mask portion. 
     
     
         69 . The apparatus as claimed in any one of  claims 60  to  66 , further comprising an active cooling member. 
     
     
         70 . The apparatus of  claim 69 , wherein the active cooling member is selected from a group comprising water-cooling, air-cooling, solid-state cooling, and fans. 
     
     
         71 . An apparatus for forming a plastic film comprising:
 (a) a heating element, and   (b) a mechanism to prevent or reduce heating in select certain sections where optical clarity is desired.   
     
     
         72 . The apparatus of  claim 71 , further comprising of a vacuum member and air suction port on a mould. 
     
     
         73 . The apparatus of  claim 71  or  72  where said mechanism is a heat masking element. 
     
     
         74 . The apparatus of  claim 73 , wherein one or more of said heat masking elements is an insulation material directly covering the heating element by an attachment member, wherein the insulation material is selected from a group comprising of insulating ceramic, mineral fiber, tool-makers insulation board, Teflon, and DME thermal insulation sheet. 
     
     
         75 . The apparatus of  claim 73 , wherein one or more of said heat masking element is embedded into the heating element. 
     
     
         76 . The apparatus of  claim 71  or  72  where said mechanism is a passive cooling element. 
     
     
         77 . The apparatus of  claim 76 , wherein the passive cooling member is selected from a group comprising an air compressor and air outlet, a vacuum pump and vacuum port, and controlling the material thickness in the heat-mask portion. 
     
     
         78 . The apparatus of  claim 71  or  72  where said mechanism is an active cooling element. 
     
     
         79 . The apparatus of  claim 78 , wherein the active cooling member is selected from a group comprising water-cooling, air-cooling, solid-state cooling, and fans. 
     
     
         80 . A protective face shield comprising:
 (a) a cylindrical-shaped body member,   (b) a forehead-engaging rearward member, and   (c) a three dimensional feature with varying angles along multiple axes at the bottom of the face shield, thereby improving operational safety and user comfort.   
     
     
         81 . The protective face shield of  claim 80  wherein said face shield further comprises a head attachment member for securing said face shield to a wearer's face. 
     
     
         82 . The protective face shield of  claim 81 , wherein said head attachment member comprises a strap attached to said cylindrical-shaped body member. 
     
     
         83 . The protective face shield of  claim 82 , wherein said strap further comprises a fastener or coupling member for strap length adjustment. 
     
     
         84 . The protective face shield of  claim 82 , wherein said strap is a single elastic head strap. 
     
     
         85 . The protective face shield of  claim 84 , wherein said single elastic head strap further comprises a fastener or coupling member for strap length adjustment. 
     
     
         86 . The protective face shield of  claim 82 , wherein said strap comprises two head straps with fasteners or coupling member for strap length adjustment. 
     
     
         87 . The protective face shield of  claim 81 , wherein said head attachment member comprises a pair of clips for the engagement to the user's eyewear bows. 
     
     
         88 . The protective face shield of  claim 87 , wherein said pair of clips made by thermoforming said cylindrical-shaped body member. 
     
     
         89 . The protective face shield of  claim 81 , wherein said head attachment member comprises an adjustable ratchet headgear. 
     
     
         90 . The protective face shield of  claim 80  or  89 , wherein said forehead-engaging rearward member is located at the top of said cylindrical-shaped body member. 
     
     
         91 . The protective face shield of  claim 90 , wherein said forehead-engaging rearward member is a three dimensional feature with varying angles along multiple axes formed by selectively thermoforming said cylindrical-shaped body member. 
     
     
         92 . The protective face shield of  claim 91 , wherein said forehead-engaging rearward member is a tripod head contact member thermoformed from said cylindrical-shaped body member. 
     
     
         93 . The protective face shield of  claim 90 , wherein said forehead-engaging rearward member is cushion member attached to said cylindrical-shaped body member. 
     
     
         94 . The protective face shield of  claim 93 , said cushion member is a tripod of cushion member selected from the group consisting of foam, gel pad, silicone, urethane, or other polymer or fabric with acceptable skin contact. 
     
     
         95 . The protective face shield of  claim 91 ,  92 ,  93 , or  94 , wherein said forehead-engaging rearward member creates added ventilation. 
     
     
         96 . The protective face shield of  claim 95 , wherein said forehead-engaging rearward member further comprises vent holes for added ventilation. 
     
     
         97 . The protective face shield as claimed in any of  claims 80  to  96 , wherein said forehead-engaging rearward member further comprises an adhesive layer for improved engagement to the wearer's forehead. 
     
     
         98 . The protective face shield as claimed in any of  claims 80  to  97 , wherein the face shield further comprises a coating selected from the group comprising of scratch resistant coating, tint coating, anti-fog coating, anti-glare coating, anti-reflection coating, stain-proof coating, and UV light filtering or blocking coating. 
     
     
         99 . The protective face shield as claimed in any of  claims 80  to  98 , wherein said cylindrical-shaped body member, said forehead-engaging rearward member, and said three dimensional feature with varying angles along multiple axes at the bottom of the face shield are all created from a single piece of semi-rigid plastic film. 
     
     
         100 . The protective face shield of  claim 99 , wherein said forehead-engaging rearward member, and said three dimensional feature with varying angles along multiple axes at the bottom of the face are created by selectively thermoforming said cylindrical-shaped body member, thereby maintaining optical clarity for said cylindrical-shaped body member that is not thermoformed. 
     
     
         101 . The protective face shield of  claim 99  or  100 , wherein said piece of semi-rigid plastic film is selected from a group comprising PET, polycarbonate, polypropylene, OPS, BOP, PVC, polyester, acrylics, polystyrene, rigid vinyl (RPVC) polyester, polyethylene, clear acetate plastic, clear ABS, and other chemistries. 
     
     
         102 . The protective face shield of  claim 99  or  100 , wherein said cylindrical-shaped body member is substantially flat thereby obtaining optical clarity and said three dimensional feature with varying angles along multiple axes at the bottom of the face shield, formed by selectively thermoforming said cylindrical-shaped body member, thereby improving operational safety and user comfort.