53results about "Spiro-condensed pyran compound compositions" patented technology

Various non-limiting embodiments of the present disclosure relate to photochromic materials comprising a reactive substituent. For example, the present disclosure contemplates photochromic materials, such as photochromic naphthopyrans and indeno-fused naphthopyrans having a reactive substituent comprising a reactive moiety linked to the photochromic naphthopyran by one or more linking groups. In certain non-limiting embodiments, the reactive moiety comprises a polymerizable moiety. In other non-limiting embodiments, the reactive moiety comprises a nucleophilic moiety or an electrophilic moiety. Other non-limiting embodiments of the present disclosure relate to photochromic articles, compositions, and methods of making the photochromic articles, wherein the photochromic articles and compositions comprise the photochromic naphthopyrans described herein.

An reimageable medium composed of: a substrate; and a photochromic material, wherein the medium is capable of exhibiting a color contrast and an absence of the color contrast, wherein the medium has a characteristic that when the medium exhibits the absence of the color contrast and is then exposed to an imaging light corresponding to a predetermined image to result in an exposed region and a non-exposed region, the color contrast is present between the exposed region and the non-exposed region to form a temporary image corresponding to the predetermined image that is visible for a visible time, wherein the medium has a characteristic that when the temporary image is exposed to an indoor ambient condition for an image erasing time, the color contrast changes to the absence of the color contrast to erase the temporary image in all of the following: (i) when the indoor ambient condition includes darkness at ambient temperature, (ii) when the indoor ambient condition includes indoor ambient light at ambient temperature, and (iii) when the indoor ambient condition includes both the darkness at ambient temperature and the indoor ambient light at ambient temperature, and wherein the medium is capable of undergoing multiple cycles of temporary image formation and temporary image erasure.

A reimageable medium for receiving an imaging light having a predetermined wavelength scope, the medium composed of: a substrate; a photochromic material capable of reversibly converting among a number of different forms, wherein one form has an absorption spectrum that overlaps with the predetermined wavelength scope; and a light absorbing material exhibiting a light absorption band with an absorption peak, wherein the light absorption band overlaps with the absorption spectrum of the one form.

A reimageable medium including a transparent substrate having a first side and any opposing side, a protective layer and an imaging layer. The protective layer can be located on the first side of the transparent substrate and the imaging layer can be located on the opposing side of the transparent substrate.

An image forming method composed of: (a) providing a reimageable medium composed of a substrate and a photochromic material, wherein the medium is capable of exhibiting a color contrast and an absence of the color contrast; (b) exposing the medium to an imaging light corresponding to a predetermined image to result in an exposed region and a non-exposed region, wherein the color contrast is present between the exposed region and the non-exposed region to allow a temporary image corresponding to the predetermined image to be visible for a visible time; (c) subjecting the temporary image to an indoor ambient condition for an image erasing time to change the color contrast to the absence of the color contrast to erase the temporary image without using an image erasure device; and (d) optionally repeating procedures (b) and (c) a number of times to result in the medium undergoing a number of additional cycles of temporary image formation and temporary image erasure.

A protective, switchable layer adapted for use in transient imageable documents is disclosed. The protective layer can be disposed on an underlying photochromic layer and enables writing or imaging the underlying layer. The protective layer prevents unintentional writing on the photochromic layer, such as can otherwise occur from exposure to certain wavelengths of light.

A reimageable medium including a transparent substrate having a first side and any opposing side, a protective layer and an imaging layer. The protective layer can be located on the first side of the transparent substrate and the imaging layer can be located on the opposing side of the transparent substrate.

The present invention provides a reversible piezochromic system that gives high contrast images upon an application of pressure to the system. The system has a short color-reversal time and can be prepared inexpensively by admixing a suitable electron donating compound and a suitable electron accepting compound. The reversible piezochromic systems of the present invention are useful for preparing a printing ink that can be used to print, for example, banknotes, to prevent forgeries.