Abstract: A liquid crystal film laminate embodies an indicator component and a supportive and protective component removable from the indicator component to provide maximum flexibility and minimum mass in the resulting indicating article. The indicator component includes a liquid crystal film and may include a protective layer and/or an adhesive layer. The film has an outer surface which forms one of two opposite side surfaces on the indicator component. The supportive and protective component includes two release surfaces provided by at least one release sheet, such release surfaces separably contacting respective ones of the indicator component side surfaces in covering relation thereto, for removably supporting and protecting the indicator component. The outer surface of the film thereby is exposed to unobstructed view upon removal of the supportive and protective component, for maximum clarity of the indication given by the film. The maximum total thickness of the indicator component preferably is about 4 mils.

Abstract: A method of effecting venipuncture in the human body includes the steps of cooling the skin over a venous area of the body by applying a cold pack thereto and providing on the cooled skin in heat exchange relation thereto a layer of an enantiotropic cholesteric liquid crystalline phase material exhibiting a mesophase color change at a temperature reached by the skin due to venous blood flow, warming the cooled skin by venous blood flow in such area thereby to produce a mesophase color change in the material delineating a vein therebeneath, and directing an instrument for venipuncture to a site in such area indicated by the delineation to constitute the location of a vein.

Abstract: An alkyd-type polymeric plasticizing resin or castor oil is incorporated in a mixture of a polyvinyl butyral film-forming polymer and a cholesteric liquid crystalline phase material, to provide a composition which when in the form of a film exhibits accentuated intensity and contrast of visible light waves reflected by the material.

Abstract: A composition of matter having thermal color responsive characteristics and adapted for exhibiting improved color contrast includes an enantiotropic cholesteric liquid crystalline phase material, and at least two oil-soluble dyes dissolved in the material in a total dye concentration of 0.01-1% by weight of the composition, each of the dyes reflecting light of a different wave length in the range of 400 to 700 nanometers, and said dyes together absorbing light of substantially all wave lengths within said range.