The feature of a paper that
causes it to appear shiny, when light hits a paper's surface, the direction of
the reflected light waves determines a paper's gloss. A paper that has
undergone extensive calendaring or has had its exterior greatly
polished, will mirror the light primarily as analogous rays, or all in the equivalent
direction This is what causes a paper surface to be shiny, or
"glossy." The opposite of a glossy surface, a matte surface, is much less polished,
so the light rays that strike it are reflected in different directions (or more
diffusely) due to small surface contours. Gloss is related to paper smoothness,
but there is no clear correlation between the two qualities. Glossy papers are
used in some printing jobs to increase the gloss or color brilliance of the
printing ink (glossy paper reflects light back through the ink), and less
glossy papers are used in other printing jobs to reduce eyestrain (the high
degree of reflected light makes text printed on glossy paper hard to read).
Paper gloss is measured using a glossmeter, which compares the amount of light reflected from a paper
surface to the amount of light hitting it. Paper gloss may differ with grain direction, so separate
glossmeter readings may be taken with the grain and against the grain and then averaged. Since papers
also exhibit two-sidedness (i.e., wire side vs. felt side), an average gloss level may be
provided for each side of the paper. "Perfect gloss," as determined
by referencing a gloss standard (i.e., polished black glass), is near 100 gloss
units. Matte papers register generally less than 20 gloss units, while dull-finish papers range up to 40 gloss units.
The term gloss also refers to the degree
of shine of a printed ink. Certain inks, such as high-gloss inks, dry to a high degree of gloss. The key to glossy inks is the
maximization of ink holdout, as it is premature absorption
of the ink vehicle into the paper before it can dry by oxidation that decreases gloss.
Goodrich
Agrochem's tailor made biopolymer range of coating & laminating binder
helps to increase the paper gloss.
For more information please visit
Web: http://goodrichworld.com/products/coating-binder-cellbond.aspx
Web: http://goodrichworld.com/products/coating-binder-cellbond.aspx
A gloss meter comprises an incandescent light source which is directed at the test surface at a specified incidence angle and a receptor novo gloss
ReplyDelete