← Back to Patent Explorer
US3941901A Expired / Lapsed US ⏱️ 0.0 years remaining

Surface alignment method for liquid crystal cells and production of polarizers therefor

Assignee: Hoffmann La Roche Inc
•
Filing: 1974-02-15
•
Granted: 1976-03-02
•
Expires: 1994-02-15
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Method for producing homogeneous surface alignment of liquid crystal materials by applying to the surfaces of transparent plates bounding a liquid crystal film a polymer which is subjected to a shear thinning technique to cause elongation and alignment of long chain polymers. In certain embodiments of the invention, the surfaces are coated with a polymer treated with a dichroic dye such that a polarizing film is formed adjacent the liquid crystal film. This eliminates the need for separate polarizers on opposite sides of a liquid crystal display.

Inventors

  • 👤 Thomas B. Harsch

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:59
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133528; G02F1/1337; G02F1/133711

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 73 words
A method for aligning a long chain vinyl polymeric surface for subsequent homogeneous orientation of liquid crystal molecules, which comprises dissolving the long chain polymer in a solvent, applying the solution of the polymer and solvent to a substrate, subjecting the thus-applied polymer to shear forces to effect shear thinning and alignment of the long chain polymer molecules, and evaporating said solvent from the long chain polymer, leaving the long chain molecules aligned.
Claim 2
Independent Claim 73 words
A method for aligning a long chain vinyl polymeric surface for subsequent homogeneous orientation of liquid crystal molecules, which comprises dissolving the long chain polymer in a solvent, applying the solution of the polymer and solvent to a substrate, subjecting the thus-applied polymer to shear forces to effect shear thinning and alignment of the long chain polymer molecules, and evaporating said solvent from the long chain polymer, leaving the long chain molecules aligned.
Claim 3
Dependent Claim 25 words
The method of claim 1 wherein said shear forces are created by passing a squeegee over the solution after it is applied to the substrate.
Claim 4
Dependent Claim 35 words
The method of claim 1 wherein said shear forces are created by passing a substrate with the solution applied thereto under a roll having a different tangential speed than the lineal speed of the substrate.
Claim 5
Dependent Claim 23 words
The method of claim 1 including the step of incorporating into said polymer a dichroic substance whereby the polymer coating becomes a polarizer.
Claim 6
Dependent Claim 104 words
In the method for forming a liquid crystal cell from transparent parallel plates having transparent conductive material on the facing surfaces thereof, the steps of dissolving a long chain vinyl polymer in a solvent, applying the solution of the long chain polymer and solvent to the surfaces of said transparent plates onto which the conductive material has been previously deposited, subjecting the thus-applied polymer on the respective plates to shear forces to effect alignment of the long chain polymer molecules, causing said solvent to evaporate, and depositing a layer of liquid crystal material between said plates and in contact with the thus-applied polymer coating.
Claim 7
Dependent Claim 104 words
In the method for forming a liquid crystal cell from transparent parallel plates having transparent conductive material on the facing surfaces thereof, the steps of dissolving a long chain vinyl polymer in a solvent, applying the solution of the long chain polymer and solvent to the surfaces of said transparent plates onto which the conductive material has been previously deposited, subjecting the thus-applied polymer on the respective plates to shear forces to effect alignment of the long chain polymer molecules, causing said solvent to evaporate, and depositing a layer of liquid crystal material between said plates and in contact with the thus-applied polymer coating.
Claim 8
Dependent Claim 33 words
The method of claim 5 including the step of arranging said plates with the liquid crystal therebetween such that the molecular alignments on the respective plates are at right angles to each other.
Claim 9
Dependent Claim 20 words
The method of claim 5 including the step of incorporating into said polymer coatings a dichroic substance to form polarizers.
Claim 10
Dependent Claim 33 words
The method of claim 5 including arranging said parallel plates to have the respective alignments of the polymer molecules forming an angle relative to one another, thereby effecting a twisted liquid crystal structure.
Claim 11
Dependent Claim 18 words
The method of claim 8 including providing a nematic liquid crystal having positive dielectric anisotropy between the plates.
Claim 12
Dependent Claim 29 words
A method according to claim 1 wherein selection of said polymer is made from the group consisting of polyvinyl alcohol, polyvinyl butyral, polyvinyl formal, polyvinyl glyoxal and polyvinyl glutaral.

References Cited (Backward Citations)

US3235631A Cited
US3468700A Cited
US3507682A Cited
US3731986A Cited
US3809456A Cited
US3795516A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-02 1979-09-01 1980-03-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-02 1983-09-01 1984-03-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-02 1987-09-01 1988-03-02 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag