Opacity, opaque

Opacity opaque Color yellowish Phase at 25"C solid Density 19.3 g/mL... 

White Pigments. Opaque white pigments commonly used in inks, in order of decreasing opacity, ate titanium dioxide and zinc oxide. TiO is by fat the most popular white pigment. Mixtures of whites ate often made with the various colored pigments to add opacity or to make pastel colors. 

Optical Properties. Owing to the high crystallinity of HDPE, most thick-waHed articles made from HDPE resins are opaque. Significant surface roughness can also add to the opacity. Thin HDPE film, in contrast, is translucent, but its transparency is significantly lower than that of LDPE or LLDPE film. The ultraviolet transmission limit of HDPE is around 230 nm. 

To opacify the adhesives. Opacity is required for aesthetic reasons or as an indication of how uniformly the adhesive is applied. Titanium dioxide is used to make the adhesive opaque. 

In most GRPs debonding can occur after even a small number of cycles, even at modest levels. If the material is translucent, the buildup of fatigue damage can be observed. The first signs (for example, with glass-fiber TS polyester) are that the material becomes opaque each time the load is applied. Subsequently, the opacity becomes permanent and more pronounced, as can occur in... 

Commercially available types, which are made from two crystal modifications, differ primarily in terms of opacity. The more transparent version is also somewhat more bluish. The very opaque modification is much more stable to a variety of... 

P.Br.42 affords somewhat dull, yellowish shades of brown in industrial finishes, such as alkyd melamine resin systems. The coating shows a certain opacity, the pigment, however, is recommended to be used in metallics and as opaque pigment as well. 

Cataracts refer to the opacity of the lens of the eye or of its capsule. Symptoms of cataracts are a progressive decrease in visual acuity as the lens becomes visibly opaque. Cataracts are usually painless but pain may be an accompanying symptom if the cataract swells and secondary glaucoma develops. 

Opaque cornea, iris not discernible through the opacity... 

On the progressive dehydration of a silica gel the gel rapidly contracts to a certain point. Van Bemmelen s first inversion point after which but little contraction takes place. On continued dehydration the clear gel suddenly becomes cloudy, then opaque, and finally loses its opacity again—Van Bemmelen s second point of inversion, when the water content has sunk to a ratio of one mol. of water to one of silica. 

Colorless materials range from being almost totally transparent to being opaque. The opacity is related to the light-scattering process occurring within the material. 

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