← Back to Patent Explorer
EP0083552A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Sheet material

Assignee: Novartis AG
•
Filing: 1982-12-06
•
Granted: —
•
Expires: 2002-12-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A transparent sheet material which is suitable for projection on overhead projectors comprises coated onto a support a binder layer containing discrete particles of an organic polymer which has substantially the same refractive index as the binder, the polymer comprising from 0.5 to 30% by weight of the binder.The coating gives a good key for typewritten characters produced by carbon ribbon or ink ribbon typewriters, for writing with e.g. ball-point pen, pencil, water or solvent based ink pens, Indian ink and inked rubber stamps.

Inventors

  • 👤 Stephen Roderick Dr. Postle
  • 👤 James Doyle

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-06 17:56
CPC Classifications
B; B44; B44D; B44D3/00; B44D3/18; B41; B41M; B41M5/00; B41M5/50; B41M5/502; B41M5/508; B41M5/52; C; C08; C08J; C08J7/00; C08J7/04; C08J7/0427; C08J7/043; B41M5/5236; B41M5/5254; B41M5/5263; B41M5/5272; C08J2367/00; C08J2367/02; C08J2433/00; C08J2433/04; C08J2433/06; C08J2433/10; C08J2433/12; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/25; Y10T428/254; Y10T428/31504; Y10T428/31507; Y10T428/31725; Y10T428/31768; Y10T428/31801

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 56 words
A transparent sheet material, which comprises coated onto a transparent support, a transparent binder layer having dispersed therein colourless organic polymer beads of from 0.5 µm to 40 µm in size and which have substantially the same refractive index as the binder, the organic polymer beads comprising from 0.5 to 30% by weight of the binder.
Claim 2
Dependent Claim 56 words
A transparent sheet material, which comprises coated onto a transparent support, a transparent binder layer having dispersed therein colourless organic polymer beads of from 0.5 µm to 40 µm in size and which have substantially the same refractive index as the binder, the organic polymer beads comprising from 0.5 to 30% by weight of the binder.
Claim 3
Dependent Claim 22 words
A material according to claim 1, wherein the particle size range of the polymer beads is from 1.5 µm to 5.0 µm.
Claim 4
Dependent Claim 21 words
A material according to claim 1, wherein the layer thickness of the binder layer is from 0.5 µm to 20 µm.
Claim 5
Dependent Claim 28 words
A material according to claim 3, wherein the layer thickness of the binder layer is just slightly less than the mean average particle size of the polymer beads.
Claim 6
Dependent Claim 27 words
A material according to claim 1, wherein the binder is gelatin, modified gelatin or a synthetic polymer latex or a mixture of gelatin and a polymer latex.
Claim 7
Dependent Claim 24 words
A material according to claim 1, wherein the binder is gelatin or a butylacrylate/styrene latex and the organic polymer is polymethylmethacrylate in bead form.
Claim 8
Dependent Claim 25 words
A material according to claim 1, wherein the material of the support is cellulose triacetate, cellulose acetate-butyrate or subbed biaxially oriented polyester polystyrene or polycarbonate.
Claim 9
Dependent Claim 35 words
A material according to claim 1 which has on at least one surface alphanumeric symbols which have been applied by typing using a carbon ribbon or which have been applied in a xeroxgraphic copying machine.
Claim 10
Dependent Claim 67 words
A process for the preparation of a transparent sheet material according to claim 1, which comprises coating onto a transparent sheet material a transparent binder layer having dispersed therein colourless organic polymer beads of from 0.5 µm to 40 pm in size and which have substantially the same refractive index as the binder, the organic polymer beads comprising from 0.5 to 30% by weight of the binder.
Claim 11
Dependent Claim 14 words
Use of the material according to claim 8 for projection on an overhead projector.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag