CD screen printing process and corresponding points analysis three

Sunnet

Sunnet refers to the process of copying and copying the Philippine graphic on the screen. It can generally be divided into the following steps:

Clean Film--Fleming Photo Location Positioning on Screen--Exposure to Exposure Machine

First, to clean the film is to avoid some of the dust on the film attached to the debris after exposure on the screen to form some trachoma and blemishes in the cleaning aspects should pay attention to matters:

1. Do not use solvents that can corrode PVC sheets when cleaning.

2, when cleaning should not be too much effort or easy to cause film scratches and film off.

3, If you do not use a hairdryer to dry the residue of the solvent, it will affect the printing.

Second, some things that should be noted in the orientation of film

1. Due to the mesh characteristics of the screen weaving and the mesh characteristics of the screen tuning film, the grid meshes of the two are easily overlapped and the collision collision network is easily formed to form some irregular lines. This is called a moiré pattern. However, the purpose of reducing or eliminating the moiré can be achieved by adjusting the mesh-line intersection angle, which is the angle positioning problem of the mesh tune film on the screen. The actual angle selection method is to superimpose dot screens on the stretched screen to observe the light. The screens rotated to the film and the wires of the cloth do not produce any visible lines.

2. The positioning of the film should also take into consideration whether the position of the graphic text on the screen operation can be adjusted to the position defined by the printer base.

3. The positioning of the film angle should take into account that the angle difference between the screen plates of the multicolor printing should be within the adjustable range of the printing machine.

Third, pay attention to the machine exposure

1. The glass of the printing machine should be kept clean, and the area where the screen is placed must not contain any foreign matter that affects light transmission. It is also best to avoid scratched areas. Traces on the screen will also be traced when scratches occur on screens that require shorter sun exposures.

2. Expose the screen when it is best placed directly above the exposure light source.

3. The exposure light source should be started after the vacuum is drawn to a stable value.

4, the exposure time should be based on film depth, exposure light source power, exposure light source and the distance between the screen for appropriate adjustments.

Fourth, screen printing requirements for film:

Screen printing imposes some requirements on printed film due to limitations of its plate making methods and screen materials.

1. The film surface of the film should face upwards and should be positive

2. The number of film lines of the film should be matched with the specifications of the mesh cloth used by the company. The higher the number of wires, the higher the requirement for the mesh cloth and the higher the fluidity of the ink used, but the printed text. The better the effect, the higher the resolution. Screen printing film should not exceed 133 lines in general.

Development

Care should be taken when developing:

1, the development must be sufficient. The uncured photosensitive film must not have any residue, and the cured photosensitive film cannot be washed away.

2, the development time can not be too long or the photosensitive layer will swell adhesive force will decline, thus affecting the resistance force.

3. The pressure of the flushing water gun used during development should not be too great and the spray should be uniform.

4. When developing a film with gradient effect, it should try to avoid flushing directly with the pressurized water gun.

Drying, sealing edge mending leakage 1, in the drying after development should pay attention to avoid the development of residual water flow caused by "flow marks."

2. Carefully observe the light of the screen before affixing to the net, and repair the bad phenomena such as the trachoma and the film that are not firmly bonded to the screen.

3. Seal all the areas other than the film and graphics that should not be able to penetrate the ink with the sealing paste. When the sealing is completed, the sealing medium slurry should be as far as possible. Do not form rugged crucibles to avoid frequent scratching during printing.

(to be continued)