Luminescent writing or display device

• US 4,927,748 A
• Filed: 02/27/1989
• Issued: 05/22/1990
• Est. Priority Date: 02/27/1989
• Status: Expired due to Term

• Current Assignee: Benjamin Kinberg
• Original Assignee: Benjamin Kinberg
• Inventors: Kinberg, Benjamin
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Szczepanik, Valerie
• Application Number:
  US07/315,611
• Time in Patent Office: 449 Days
• Field of Search: 434/410
• US Class Current: 434/410
• CPC Class Codes: B43L 1/006 with luminescent substances
• CPC Class Codes: B43L 1/123 Flexible writing surface or backing
• CPC Class Codes: G09F 13/20 with luminescent surfaces or parts luminescent compositions C09K11/00; light sources using luminescence F21K2/00

Abstract

A display or writing slate capable of producing luminescent images upon the application of pressure thereon which can be readily erased and repeatedly used that includes a pair of over-lying sheets, one of which is translucent or transparent, containing a luminescent dye or pigment and the other of which is opaque, and which sheets have a smooth surface at their interface. At least one of the sheets is formed of a pliable plastic with its interface surface tending to adhere to the interfacing surface of the other sheet when a pressure is applied thereto to produce the luminescent images. The improvement resides in the incorporation of a non-migrating dye or pigment in the translucent or transparent sheet so as to resist the migration of the luminescent dye or pigment from the translucent or transparent sheet to the interface surface of the other sheet.

Claims

1. An improved writing and display device for producing a luminescent image upon the application of a pressure thereon comprising

a transparent plastic sheet having means comprising a primary low volatile plasticizer, and containing a luminescent tinting material integrally dispersed throughout said plastic sheet,

an opaque white sheet disposed contiguous to said transparent sheet to be in direct interfacing relationship therewith,

said transparent sheet and tinting materials therein being in overlying relationship and in direct contacting relationship to said opaque sheet,

and said sheets each having an exposed smooth surface for direct contact at the inteface thereof,

said means being capable of prohibiting the migration of said tinting material from said transparent sheet and onto said underlying opaque sheet in direct contact therewith,

and at least one of said sheets being pliable so that upon the application of pressure thereon, the respective smooth surfaces of said sheets are urged into intimate contact at the points of the applied pressure to form a luminescent image along the points of applied pressure that will be retained so long as said sheets are adhered to one another along the points of applied pressure,

whereby any protective insert between said transparent and opaque sheet during non-use of said display device is rendered unnecessary.

2. An improved writing and display device as defined in claim 1 and including

a rigid backing member for said opaque sheet,

means for securing said transparent sheet relative to said opaque sheet along one edge thereof, wheeby said transparent sheet is disposed in free contiguous overlying relationship with said opaque sheet will not bleed thereon.

3. An improved writing and display device as defined in claim 1 wherein said tinting material comprises a luminescent pigment.

4. An improved writing and display device as defined in claim 2 wherein said transparent sheet is substantially co-extensive in size to said opaque sheet, and said transparent sheet being readily separable from said opaque sheet for effecting the erasure of any luminescent image formed thereon.

5. An improved writing and display device for producing a luminescent semi-permanent image upon the application of pressure thereon comprising

a rigid backing member,

an opaque plastic sheet secured to said backing member,

said opaque plastic sheet having a white smooth surface on at least one side thereof,

a transparent plastic sheet disposed contiguous to said opaque sheet,

said transparent sheet having a smooth surface disposed into direct contiguous interfacing relationship with said white surface of said opaque sheet, and

said transparent sheet being formed as a vinyl plastic sheet having means comprising a primary low volatile plasticizer tinted with a luminescent material integrally dispersed throughout said transparent sheet, said means being capable of prohibiting the migration of said dispersed luminescent material out of said transparent vinyl plastic sheet,

said transparent sheet and opaque sheet being substantially co-extensive in size,

means for hingedly securing said sheets whereby one of said sheets can be readily separated from the other to effect the erasure of any image formed thereon,

at least one of said sheets being pliable so that upon the application of pressure thereon, the direct interfacing surfaces of said sheets are urged into intimate contact to co-adhere to one another at the points of applied pressure to form a luminescent image in accordance with the points of applied pressure whereby said image is retained until said sheets are separated along said points of applied pressure, and

said transparent sheet and tinting material dispersed therein being capable of being in direct contact with said opaque sheet without having the luminescent material dispersed therethrough migrating out of said transparent sheet and onto said opaque sheet in contact therewith, whereby any protective insert between said transparent sheet and opaque sheet during non-use of said display device is rendered unnecessary.