Quality Control Methods for Printed Materials on Different Paper Types

In the packaging printing process, there are often different materials used to print the same or similar layout, such as product packaging, trademarks, manuals and other series of printing products, general printing layout graphics or logo colour design is basically the same, but due to the differences in the characteristics of the substrate, some of the products used in the printing equipment, ink performance and process form is not necessarily the same, and customers often require series products of the Printing colour requirements to achieve basic consistency, there can be no obvious colour difference. Production of the actual process shows that different materials of the series of printed ink quality control has some difficulty, the need for technology on the process of careful design and operation of the technology of careful control, in order to get a better printing quality results to meet the customer’s quality requirements.
Quality requirements.

First, the characteristics of the series of printed materials and process to determine the method of analysis

　　The so-called series of printed products is the same product inside and outside the packaging specifications of different or complete sets of products using different printing materials, but the graphic layout structure or colour is the same or similar. Due to differences in material characteristics or printing layout specifications, the adaptability of the printing process is also very different. Such as the outer packaging of corrugated cardboard boxes, colour box surface printing materials such as whiteboard, kraft card or boxboard, carton packaging materials are whiteboard, kraft card, white card, glass card, coated card, PE lamination paper, etc., flexible packaging plastic film, cellophane, tissue paper, oleophobic paper, copy paper, offset paper, vacuum aluminized paper, laser paper and so on. Corrugated cardboard thickness, surface flatness characteristics, as well as PE lamination paper, plastic film, cellophane, tissue paper, vacuum aluminised paper printing process, from the characteristics of the material and product packaging safety, health quality considerations, suitable for flexo printing with water-based ink, can better ensure product quality. For the pre-printing process of the colour box face paper, colour box printing’ target=’_blank’>Colour Box Printing whiteboard paper, kraft card; vacuum aluminium paper, laser paper and other materials, the number of large quantities can be used gravure or flexo process, which can be made to print the quality and cost of production have been better balanced. For the number of about 100,000 prints of whiteboard, kraft card, white card, glass card, coated card products, as well as glossy paper, copy paper, offset paper, vacuum aluminised paper, laser paper can be used offset printing process is more appropriate. Among them, glossy paper, copy paper, low quantitative, not suitable for high-speed automatic paper feed, can be used to print low-speed 01 offset press, in order to better ensure the overprint quality of the product.

　　Second, we must pay attention to the pre-press layout design process technology control

　　Now many printed products are provided by the customer’s own design or advertising company design, production of electronic manuscripts, due to their incomplete understanding of the printing process, often resulting in the production of manuscripts, can not be adapted to the requirements of the printing process. To the same anilox structure layout of the series of printed materials, for example, due to the use of different printing materials, printing colour will appear larger differences. Is the same with offset printing process printing paper plate (whiteboard material) and paper cups (single-sided PE lamination paper) of these two products, due to the smoothness of the surface of the whiteboard material is good, the amount of ink absorption will be less, while the surface of the single-sided PE lamination paper is relatively rougher, the amount of ink absorption to be a little larger, with the two kinds of material printing anilox structure of the same layout, the colour will be a big difference, the general single-sided PE lamination paper printing colour is obviously lighter than the whiteboard paper, by the amount of ink, by the amount of ink, by the amount of ink, by the amount of ink, by the amount of ink, by the amount of ink, by the amount of ink. White paper, ink, pressure adjustment often can not be better to overcome the material printing performance differences in the colour problem. Generally through the plate design will be printed on single-sided PE lamination paper main colour dot area appropriately adjusted a little larger, in order to make the printing colour to reach close. Therefore, when receiving the same anilox layout structure and substrate materials are different series of printed products, we must first carefully analyse the original layout structure and substrate material properties, and then determine a reasonable plate design scheme, that is, according to the material gloss, printing ink absorption properties, reasonable adjustment of a product layout of the dot area to ensure that the colour of the different materials printed close to each other.

　　Third, pay attention to the direction of the collocation process technology control

　　Multi-platen structure of printed matter, a print sheet is usually spelled out several different varieties of layout, if you do not take into account the different varieties of printing colour differences, but the colour differences between the different varieties of spelling in the same longitudinal direction, then, once the longitudinal layout of which a certain layout of the printing colour appears lighter or darker, it will be difficult to locally adjust the amount of ink output through the ink bucket to achieve the corresponding longitudinal layout of a certain variety of ink color control, ink, ink and ink. Ink colour control of the layout, ink colour adjustment will often lose sight of the situation, can not take into account the overall vertical layout of the printing colour. Therefore, for the paper discs, paper cups, trademarks and other products, each longitudinal position is best to spell the same species or colour.