How do printing enterprises do OEM Cheap Binding Notepad color difference control?

How do printing enterprises do OEM Cheap Binding Notepad color difference control?

With many years of printing production and management experience, the author believes that from the process, printing color difference control should be divided into pre-press, printing, printing after three stages.

Color control is the core of print quality control. In the whole production management of printing enterprises, color management is in the core position. With the continuous improvement of customers' requirements for printing quality, the ink stability of batch products is becoming more and more important, and the allowed range of product color difference is becoming smaller and smaller.

With many years of experience in printing production and management, I believe that from the perspective of the process, the control of printing color difference should be divided into three stages: pre-press, printing and post-printing. In the control process of these three stages, we should pay attention to these points: 1. Reduce the discoloration caused by parking; 2. Select all nonconforming products, mark them and centrally deal with them; 3. Be diligent, careful and attentive in work, and take every small job seriously; 4. All relevant personnel should change their bad working habits, so as to ensure the operator's execution and the manager's supervision and coordination.

Prepress control phase

In the pre-press control stage, the following points should be done:

1. When cutting paper, the paper must meet the requirements. If the paper is skewed and the knife is not fast, it will produce paper hair and paper residue, which will affect the printing.

2. Changes in printing suitability of paper caused by changes in ambient temperature and humidity should be minimized. If the paper can not be cut too far in advance, it should be covered in time after cutting and placed near the printing machine; After printing, semi-finished products and finished products should be timely covered and stored near the printing machine to reduce paper deformation, and so on.

3. Ensure that the waterway and ink road are not polluted; The proportion of wetting liquid is accurate; Water tank and ink roller meet printing requirements, no dirt, emulsification, crystallization phenomenon; Reduce the instability of ink color caused by the shutdown of dirty points and the imbalance of ink.

4. Adjust the state of printing equipment to ensure accurate and uniform pressure of roller, ink roller and water roller. Adjust the double controller and regular parts to reduce the frequent shutdown caused by improper adjustment.

5. Choose the right printing color sequence to avoid color difference caused by color sequence change.

6. When matching special color ink, ink auxiliary agent should be added according to the actual situation of text and text. Products with large text and text area should be added with adhesive removal agent, which can reduce the influence of ink transfer caused by long time printing, such as drawing ink and paper pile hair.

7. All printing parameters and raw material information should be recorded during the first printing production. Such as ink type, paper specification, glossy oil type, printing pressure, color sequence, ink quantity, production date, machine personnel shift, etc.

8. Check the thickness, surface color and smoothness of each batch of paper to determine whether the printing pressure and the influence on the ink color.

9. For products printed multiple times, the data stored before should be transferred, but the amount of ink should also be adjusted according to the change of ambient temperature and humidity. The printing pressure must be adjusted according to the thickness of each batch of paper to prevent the color difference caused by inaccurate printing pressure.

10 For long-term printing production of products, paper and ink once determined as far as possible not to change, otherwise printing parameters will change.

Printing control stage

In the printing control stage, the following points should be done:

1. When mixing the color over the plate, run more over the plate paper to make sure that the ink color runs evenly before the sample printing can be carried out to avoid the color instability caused by the change of the ink on the machine.

2. After determining the standard sample, we can officially print in batches. At the same time, we can cut a small standard sample that is easy to compare at any time.

3. Every spot check should be made to ensure that each position is checked with the small standard sample, so as to facilitate the operator to timely discover the ink color changes at each position of the product. When the ink color changes, small adjustment, large-scale adjustment must be shut down, and check to determine what factors caused the large-scale change, thoroughly solved before continuing production.

4. Do not start the machine fast and slow, to fixed speed printing, reduce the impact on the balance of ink.

5. Must do five times: frequently see the layout water, check the water tank, timely adjust the water, if necessary, wipe the water roller with alcohol; Frequently stir ink, improve ink fluidity, maintain good transfer performance; Clean the ink fountain frequently, so that there is no ink paper slag and other debris in the ink fountain; Wipe the rubber and printing plate frequently to reduce the retention of paper wool, paper powder, ink stains and ink skin on the rubber and printing plate, but also to ensure that the wipe is clean, reduce the influence of car washing water on the transfer of ink, ensure the good transfer of imprinting, to provide a reliable basis for judging the supply of ink; Check the sample frequently, at least once every 500 pieces, compare with the standard sample at any time, and find the new ink balance according to the changing situation.

6. In the printing process, every time the paper and ink, should pay attention to check whether the paper and ink is intact, reduce the shutdown caused by bad paper, paper hair, ink residue, etc., affect the quality. The ink in the ink tank should not be inked too much, and the amount of ink in the ink tank should be moderate.

7. Every time you stop and start, you should extract more proofs and try to pick out all the products with color difference.

8. Once the machine finds some local unqualified products such as color difference and dirty spots, the quantity shall be counted and stored separately, marked and recorded. After the whole order is completed, it shall be submitted to the next process together for unified storage.

9. For long edition products with large printing volume, pay attention to the ink color change caused by the printing plate and timely replace the new edition.

Post-printing control stage

In the post-printing control stage, the following points should be made:

1. Store the remaining spot ink after printing in the spot ink cartridge.

2. Clean all roller surfaces, roller pillows, water rollers, ink rollers and ink buckets to prepare for the next printing production.

3. After the printing is finished, the quantity of products should be counted, the unqualified products should be distinguished, the labels should be made, and the workshop management personnel should sign for confirmation.

4. Color difference, dirty points and other unqualified products shall not be released without concession.