Stretch screen → cleaning → scraping → exposure → development → drying → revision → hardening treatment

(a), screen pretreatment:
Due to the screen in the process of weaving and stretching, easily stained with dirt, dust, grease, if not removed, affect the fastness of sensitive adhesive, so after stretching the net, it is very important to clean the screen. General use of special screen cleaning agent or household neutral, weak alkaline detergent, do not use alkali containing oil

Detergent, after cleaning, dry for use.

(two), the preparation of diazo photosensitive glue (three to seven parts of the operation are carried out under the yellow light), the photosensitive agent is added 50-90 ml of pure water and stirred until completely dissolved, and then added 900 grams of latex, stirred evenly, standing and other bubbles disappear before use. The amount of photosensitizer depends on various types of photosensitive glue.
Preparation points:
(1) the amount of water according to the requirements of colloid viscosity.
(2) When dissolving photosensitizer, if a small amount of insoluble matter is found, do not pour into colloid.
(3) containers and instruments used in preparation should not be metal products, so as not to affect the stability of the photosensitive glue

The qualitative.
(4) the prepared photosensitive glue should be used after two hours (preferably the next day), until the bubble disappears.
(5) When the sensitizer is mixed with the colloid, it is stirred in one direction, and the pasta produces a large number of bubbles.
(6) The glue is not added with photosensitizer, and the shelf life is one year under the condition of low temperature and light protection. After mixing, the

Stay for a week. Between 2℃ and 10℃, the shelf life can be extended to three months.

(three) coating sensitive adhesive
There are two ways of manual coating and mechanical coating, usually by hand coating. Pour the photosensitive glue into the sizing machine, accounting for about half of the sizing machine, the screen plate is placed next to the support body at an Angle of 80±5 degrees, and placed firmly. Hold the sizing machine and tilt the sizing machine, so that the edge of the sizing machine and the lower end of the screen plate contact, so that the glue liquid all contact the screen. The sizing device is smooth and uniform to the top of the web version, cutting edge and screen pressure to be stable, when the coating to the upper end of about 3 cm, the sizing device back, so that the glue flow back to the sizing device, still continue to move up the sizing device to the top. At this point, all the glue back to the sizing device, the sizing device will leave the screen, and remove the screen may drip and coating process on both sides of the overflow of glue, so that it is uniform, consistent thickness. Generally, the first coating (contact surface with the substrate), to be dried and then coated scraping surface (glue scraping contact surface), the number of coating is generally 2X1, such as the production of thick plate, according to the situation, to master the number of glue.
(iv) Drying:
Drying at 30℃-45℃, the relative humidity is required to be less than 40%, in the case of dust-free flow, the screen is placed horizontally, too high temperature will cause the thermal reaction of photosensitizer, affecting development.
(V) Exposure:
Photosensitive adhesive exposure requires that the most suitable wavelength of ultraviolet light is 360-420nm.

Note:
1, exposure time and screen color, photographic adhesive coating thickness, graphic fineness and environmental temperature relationship, the specific time application exposure measurement piece, after the test to determine.
2, exposure, the film must be tightly compacted with the screen, it is best to use a vacuum air drying machine.
(vi) Development:
Soak the screen after exposure in water about 25℃ for 2-3 minutes, take it out, first wash the printing surface with strong water pressure, and then clean the whole screen with weak water pressure, it is best to use fine mist water spray washing.
(vii) Revision:
Repair trachoma and other parts that should not leak with photosensitive adhesive or mesh sealant.
(viii) Hardening treatment:
In order to make the plate mold fully solidified, improve the rate of resistance to printing, available direct sunlight for 1 hour, or exposure machine exposure for 10 minutes, for hardening treatment. For ultra-high impression, curing agent can be used for chemical hardening, the method is as follows: with combination brush pen or brush dipped hardener both sides evenly coated screen (such as mesh high death, available water paper deal with the design of hardener or small sticks to beat screen make the mesh of hardener earthquakes except) into the oven (more than 50 ℃) bake for 40 minutes。
Hardener is a strong acidic liquid, such as nylon wire, please dilute stone beam with water.