From which aspects should the printing quality of the digital direct-injection printing machine be evaluated

In the course of business transactions,Digital Direct Printing MachineAppropriate quality evaluation is particularly important. The complexity of the color printing process is well known. The production of a digital print often takes more than ten steps to complete, which involves companies, staff, etc., in different environments and at different times. The evaluation methods or requirements of stamps are different. Therefore, in this process, some specifications and corresponding observation conditions need to be formulated.

Therefore, we can only make a subjective evaluation of digital printing by restricting the external factors of the environment. In this way, it can be called fair and objective, and can reduce disputes caused by the environment. Therefore, the standard lighting environment and standard light source are necessary. of.

Color difference of digital printing

Color difference can be divided into

(1) Manuscript color difference: Reproducing the color gradation of the manuscript is the purpose of printing and copying. The highest standard of subjective evaluation is to make the digital printing and the manuscript difficult to distinguish between true and false.

(2) Same batch color difference: refers to the color error between different printed sheets of the same batch of products at the same position in the same hue zone.

(3) The color difference between different batches of the same product: refers to the color error between different batches of the same product. If the color of each batch of printing is slightly different, when they are put together, customers will feel that these products are new and old, and even suspect Whether its internal quality will be as unstable as its appearance, it will cause distrust of the product, and naturally cause the manufacturer to be dissatisfied with the quality of the printing factory.

Both customers and printers hope that the value of this color error is preferably zero. However, due to the limitations of various aspects in actual production, it is impossible to completely eliminate the color error. The only way to make the product is by strengthening the quality control of each link is The color quality difference is controlled within the specified color difference standard. Color tolerance refers to the color difference between the digital print and the original or proof proof that the customer can accept.

Whether in the printing process, orClothing digital printing machineWhen checking the quality after printing, the printing operator or quality inspector should always rely on their own feeling and experience to evaluate the color quality of the printed product based on the faithfulness and authenticity of the reproduction as the standard. The faithfulness of reproduction is the degree to which the index code printing can reproduce the color gradation of the original. Digital printing is a kind of reproduction. In the entire color reproduction process from pre-press processing to printing, the original is the basis of our work. Reproducing the color gradation of the original is the purpose of printing reproduction. It is the highest standard of subjective evaluation to make the digital printing and the original manuscript reach the level of indistinguishable from the true and false.

When there is no manuscript for comparison, the color quality of digital printing is related to the sense of reality, that is, it is required to match the memory color of most people. Most people have a preconceived habit of common objects. If the main color of the digital print is different from the color of the real object, this digital print cannot be called a high-quality copy. In short, the subjective evaluation criteria for the color quality of digital printing is to replicate authenticity, naturalness, and coordination. Of course, it sometimes changes slightly with the customer's intention or the product's purpose.

Definition of manuscripts In the past, most manuscripts came from photographic slides, photos, and hand-painted color manuscripts. In the process of color separation and proofing, if they can be close to the manuscript, it is regarded as effective color reproduction. For printing, the drafting approved by the customer is used as the criterion. As long as 90% can be followed, it is generally regarded as qualified.

But nowadays, there are more definitions of manuscripts in the computer age. For example, when customers see satisfactory colors on a computer screen or printed manuscript, they think it is a manuscript. Regardless of any type of manuscript, the colors they record or appear may not be able to be expressed under general printing conditions, because every color reproduction system has its color gamut restrictions. In the production process, the image capturer regards the actual object as the original manuscript, the color separation plate maker uses the captured photo as the original manuscript, and the printer uses the proofing as the target of color tracking.

Objective Evaluation The objective evaluation of the color quality of digital printing is to calculate the result of subjective evaluation by statistical means, and then convert it into the corresponding physical quantity, which is used as the objective evaluation standard. In this way, the influence of human factors in the evaluation can be eliminated, and the color quality of various digital printings can be fairly evaluated by standardized unified standards, and finally it can be more in line with the subjective evaluation standards of most people. The objective evaluation method mainly uses specific measuring instruments and tools, and measures some standard elements printed together with the digital printing image. Only through measurement can automatic control of digital printing quality become possible to some extent.

Color quality and production control

In order to produce high-quality colorsDigital T-shirt printing machine, It is necessary to strengthen the quality control of the production process, and the quality control mainly depends on the objective evaluation standards of the products, that is, to formulate a set of strict data specifications, and use various instruments to objectively measure and evaluate the color quality of digital printing and other Aspect quality.

The purpose of color control management is to improve the small gaps between manuscripts, proofs and products. In the printing process, if the digital printing can be spot-checked at any time, the problem can be found through the biased information, and the cause can be found in time to correct the problem, thereby ensuring the reproduction quality of the digital printing. In addition to using density as a parameter to reflect the color quality of digital printing, it is necessary to promote the CIELab chromaticity value of color as a parameter to detect the quality of digital printing.

Every link must be managed by data, and every step must be tested by testing tools, otherwise there will be many errors.