US 2003/0152849 A1 · Process for roll-to-roll manufacture of a display by synchronized photolithographic exposure on a substrate web

Abstract

This invention relates to an electrophoretic display or a liquid crystal display and novel processes for its manufacture. The electrophoretic display (EPD) of the present invention comprises microcups of well-defined shape, size and aspect ratio and the microcups are filled with charged pigment particles dispersed in an optically contrasting dielectric solvent. The liquid crystal display (LCD) of this invention comprises well-defined microcups filled with at least a liquid crystal composition having its ordinary refractive index matched to that of the isotropic cup material. A novel roll-to-roll process and apparatus of the invention permits the display manufacture to be carried out continuously by a synchronized photo-lithographic process. The synchronized roll-to-roll process and apparatus permits a pre-patterned photomask, formed as a continuous loop, to be rolled in a synchronized motion in close parallel alignment to a web which has been pre-coated with a radiation sensitive material, so as to maintain image alignment during exposure to a radiation source. The radiation sensitive material may be a radiation curable material, in which the exposed and cured portions form the microcup structure. In an additional process step, the radiation sensitive material may be a positively working photoresist which temporarily seals the microcups. Exposure of a selected subset of the microcups via the photomask image permits selective re-opening, filling and sealing of the microcup subset. Repetition with additional colors permits the continuous assembly of a multicolor EPD or LCD display.

Claims45

Dependent claims

A process for the preparation of a plurality of well-defined structures of at least one electronic device, said process including the imagewise exposure of radiation sensitive material, said process comprises the steps of:

(a) providing a support web;
(b) providing a layer of radiation sensitive composition coated on said support web;
(c) providing a pre-patterned photomask, said photomask comprises a strip formed as a continuous loop, said photomask pattern corresponding in form to at least one of said structures so as to permit an image of said structure to be projected by radiation passing through said photomask;
(d) aligning said photomask loop adjacent to said support web so that a portion of said photomask loop is in generally parallel orientation to at least a portion of said web,
(e) selectively imagewise exposing said radiation sensitive material by passage of radiation through said photomask;
(f) rolling said photomask loop in synchronized motion relative to said support web, said synchronized motion includes moving at least a portion of said photomask loop and at least a portion of said web in parallel in substantially the same direction.

3 more elements

A process for the preparation of a plurality of well-defined structures of at least one electronic device, said structures being disposed coordinate with a plurality of elements of said at least one electronic device, said process including the imagewise exposure of radiation sensitive material, said process comprises the steps of:

(a) providing a support web having a surface;
i. said support web includes a plurality of elements of said at least one electronic device;
ii. said elements being disposed in a repeated longitudinal pattern along said support web;
(b) coating a layer of radiation sensitive composition on said support web;
(c) providing a pre-patterned photomask;
i. said photomask comprises a strip formed as a continuous loop;
ii. said photomask loop is configured to have a loop face adjacent to at least a portion of said web surface;
iii. said photomask pattern includes a plurality of photomask portions, each of said photomask portions having one of pre-selected transparency to radiation and pre-selected opacity to radiation corresponding in form to one of said plurality of structures;
(d) aligning said photomask loop face in generally parallel orientation adjacent to said support web surface, including aligning in a predetermined spatial relationship at least one of said plurality of elements to at least one of said plurality of photomask portions;
(e) selectively imagewise exposing said radiation sensitive material by passage of radiation through said photomask;
(f) moving said photomask loop face in synchronized motion relative to said support web surface, said synchronized motion includes moving said loop face and said web surface in parallel in the substantially the same direction for substantially the same distance so as to maintain said alignment in a predetermined spatial relationship.

8 more elements

An apparatus for the preparation of a plurality of well-defined structures of at least one electronic device by the imagewise exposure of a layer of radiation sensitive material coated upon a support web, comprising:

(a) a web drive mechanism engaging said support web so as to movably guide said web;
(b) a pre-patterned photomask, said photomask comprises a strip formed as a continuous loop;
(c) a photomask alignment mechanism engaging said photomask, said alignment mechanism is mounted adjacent said web so as to align said photomask loop adjacent to said web so that a portion of said photomask loop is in generally parallel orientation to at least a portion of said web;
(d) a photomask drive mechanism engaging said photomask for rolling said photomask loop, said photomask drive mechanism is synchronizable with said web drive mechanism so as to permit rolling said photomask loop in synchronized motion relative to said support web, said synchronized motion includes moving at least a portion of said photomask loop and at least a portion of said web in parallel in substantially the same direction;
(e) said photomask pattern corresponds in form to at least one of said structures so as to permit an image of said structure to be projected by radiation passing through said photomask;
and
(f) a radiation source mounted in cooperative alignment with said photomask and said web so as to permit the selective imagewise exposure of said radiation sensitive material by passage of radiation through said photomask.

4 more elements

Dependencies are inferred from the claim text.

Process for roll-to-roll manufacture of a display by synchronized photolithographic exposure on a substrate web

Life of this patent

Process for roll-to-roll manufacture of a display by synchronized photolithographic exposure on a substrate web

Life of this patent

Abstract

Claims45