Silkscreen printing ink

Other aUcoxyethanols, especially 2-methoxyethanol and 2-butoxyethanol and their acetates have also been used in silkscreen printing inks. The TLV for 2-methoxyethanol and its acetate is 5 ppm (their Finnish OEL is 0.5 ppm) and 25 ppm for 2-butoxyethanol (the Finnish OEL is 20 ppm for 2-butoxyethanol and its acetate but a value of 5 ppm has been proposed. ACGIH has not set BEIs for these compounds. Limits of 3 mmol methoxyacetic acid/mol creatinine and 60 mmol butoxyacetic acid/mol creatinine has been recommended in Finland for the concentrations of the urinary metabolites. " Mean inhalation exposure levels to 2-methoxyethyl acetate from 0.2 to 1.9 ppm have ben reported. The urinary methoxyacetic acid concentrations have ranged from 0.1 to 10.7 mmol/mol creatinine. Airborne mean 2-butoxyethanol and 2-butoxyethylacetate concentrations from 0.1 to 3.2 ppm have been observed. ... 

Printing inks (silkscreen ink, rotogravure ink), clear lacquer (for plastics and coating for porous papers), other. 

This process can use either solid stencils or screen (mesh) stencils (see Figure 16.12). The latter is called screen printing and was originally known as silkscreen, as silk-type screens were employed. Present day screens are made of nylon, polyester or steel and are relatively low in cost, 45-75. Each screen may give 15,000 to 50,000 impressions. The ink is forced through the screen by a squeezer. Prior to this action the screen is separated from the item to be printed by a lift-off gap. This gap is reduced by the pressure of the squeezer whereby contact is made between the screen, ink and item. Screen inks are relatively thick, and are either air or hot air dried. The screen process can produce coarse half tones with thin inks. 

The conventional light-guide patterning is a silkscreen method to print spots on the back surface of the LGP as shown in Fig. 5.1b. Here the surface of the LGP without any element taken as mirror (M) and the ink-printed surface are taken as ink (I), so that the LGP is named Ml-LGP as shown in the figure [1,2]. 

A.3 Plastisol Silkscreen Ink Plastisol screen ink is used to print on... 

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