| 摘要 |
<p>1,249,432. Display device. NATIONAL CASH REGISTER CO. 1 April, 1970 [14 April, 1969], No. 15378/70. Heading G5C. [Also in Division G1] In a thermally stimulated display device of the type disclosed in Specification 1,138,590, a layer of microcapsules 2 containing liquid crystal material located in a polymeric binder 3 is supported on a preferably opaque substrate 1 and covered by a substantially smooth top layer 4. The transparent top layer improves the colour purity of the encapsulated liquid crystal material which is diminished by encapsulation, thus improving the contrast between the stimulated area and the background. The capsule layer can be applied to the substrate in the form of a slurry or emulsion which is allowed to dry before the transparent top layer is applied. Alternatively the capsule layer can be coated on to a preformed transparent top sheet and overcoated with an opaque back layer when dry. An electric heating element may be incorporated in or behind the opaque back layer.</p> |
