Non-bleachable

Data is also shown for bovine rhodopsin, 63, for comparison. The hydroretinals 66-68 presumably assume 9-cis or 11 -cis like conformations when bound to opsin. Retinals 67 and 68 form non-bleachable pigments, i.e., no change in their A, occurs upon exposure to room light irradiation by UV light leads to decomposition products instead of separation of the chromophore from opsin. a In MeOH. In case of split chromophores the absorption maxima of the enal moieties are given. b Protonated Schiff base with n-butylamine in MeOH. ... 

The spectral properties of wines were measured with a Varian 300 UV/Vis spectrophotometer, and wine colour density (absorbance [420 nm + S20 nm]), hue (absorbance [420 nm / 520 nm]), and non-bleachable pigments (absorbance 520 nm in presence of SO2) were determined as described by Somers and Evans... 

Figure 4. Colour properties of anthocyanin-tamin model reactions, a hue, b non-bleachable pigments,...

It was the intent of the present investigation to examine the one step bleachability of non-phenolic, water-insoluble hydroxypropyl lignin (HPL) derivatives with hydrogen peroxide in homogeneous phase (i.e., aqueous ethanol). 

This layer is applied on top of the prebaked photoresist and consists of a photo-bleachable dye and a polymer. Upon imagewise exposure to UV light, the non-masked areas bleach relatively fast, whereas the masked areas bleach only marginally (see Fig. 2). The result is an in situ mask on top of the photoresist which enhances the contrast of the aerial image. After imagewise exposure, the CEL layer is stripped and the photoresist developed. 

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