ps printing offset plate Hua Rui BRAND Conventional PS Positive plate YP-II High-quality AL plate for special purpose, Multi-layer ultra fine-grain, even coating.It has advantages of high speed, excellent dot reproduction, wide latitude of development and exposure, quick inking. It is available for printing on newspaper printing and superior color printing. Characteristics: Recommended exposure unit: 20 30 Suitable printing speed: over 75,000 iph Substrate: Litho-grade aluminum, electrochemically grained and anodized Gauge: 0.15&0.25&0.30 mm Safe Light: Yellow YP-I It has advantages of high speed, wide latitude of development and exposure, moderate grain, excellent dot reproduction. It is available for printing on newspaper printing and superior color printing. Characteristics: Recommended exposure unit: 20 30 Suitable printing speed: over 50,000-75,000 iph Substrate: Litho-grade aluminum, electrochemically grained and anodized Gauge: 0.15&0.25&0.30 mm Safe Light: Yellow Exposure Light source: lodine-gallium lamp is used as the exposure light source. Exposure time is depended on light source, the recommended exposure in the table is only a given range.We suggest that you should replace the light tube when the exposure time is 20% longer than normal exposure time. Light source: 3KW lodine-Gallium lamp, distance 1m Film: To ensure the high exposure quality, it is suggested that the density of the film should be >3.5oC when exposing the plate with the film. Exposure time: Put the 21 step-gray scale (0.15 step difference) or UGRA PCW82 control strip at the bottom of the film and the edge of the plate, select the correct exposure and developing according to the recommended condition. The optimum exposure of positive plate can be obtained when the third step of gray scale is clear after exposure and development, and the optimum exposure of negative plate can be obtained when the ninth step of gray scale is clear after exposure and development, or when the 15-20um line appears on the control strip. Developing Preparation of developing solution: Hua Rui PD developer (concentrated): water=1:5 Developing temperature: 23 oC+2 oC, if temperature is too high, it will influence dot reproduction and press life, if the temperature is too low, it cant develop completely. Developing time: Less than one minute. Retouching To remove unnecessary image or stains after developing, apply a brush with a little erasing solution to the image area, let remover stay less than 4 seconds, then rinse thoroughly with water. If remover stays there for a longer time or rinse is not thorough, the plate will be contaminated. Gumming Gum the plate surface evenly to form a protection layer after developing and rinsing. The concentration and the volume follow the manufacturers recommendation. Higher concentration or excessive volume of gum solution will influence the printing quality. Baking Baking solution: high-grade baking solution is a necessary option.. Baking time: 5 10 minutes. Baking temperature:220 240 oC. Baking conditions are strictly recommended above, shorter baking time or lower baking temperature can not reach the baking results. Longer time or higher temperature will influence the printing quality. Baking result can not be evaluated only by the color changed on the PS plate. Storage and unpacking Coating layer can be changed chemically by light and heat, so the storage conditions are recommended as follows: Temperature at 10 30 oC and humidity < 65% Unpack it under yellow light. It is suggested that the plate-making room avoid natural light.All light should be yellow light except for exposure light. Plates should be handled carefully to prevent from collision, heavy pressing and knock. The height of stacked plates should be less than 1.5 meters. Guarantee period 18 months for positive plates.12 months for negative plates