Paper ink absorption and impact on printing
The ink absorbency of paper refers to the strength of the paper's ability to absorb ink. Different types of paper have different ink absorption properties. In the papermaking industry, in order to accurately control the ink absorption performance of the paper, the following two methods are generally used. 2.IGT <br> oil absorption method using IGT printability tester (FIG. 2), under the standard test conditions with chemically pure phthalocyanine drop of dibutyl Sudan colored printed paper surface to be detected is formed a red oil Trace, multiply the reciprocal of the length of the oil mark by 1000, indicating absorbency. The longer the oil mark, the smaller the absorption. 2. Excessive ink absorption <br> The ink absorption of paper is too strong, and it will quickly absorb a large amount of binder in the ink, which usually causes the following three printing problems. This product is basically suitable for all cats and dogs. It can clean up messy hair to remove hair and dirt. Especially for pets with long hair, it can be combed and smoothed well. Combs with a denser tooth pitch can make the hair smoother and make the pet look neater and more beautiful. How to use: If your pet's coat is too thick, comb it layer by layer to avoid hurting your pet, just follow the growth direction of the pet's hair. Pet Comb,Comb Pet Grooming Tools,Pet Comb Dog Grooming Tools,Pet Comb Cat Grooming Tools DongGuan Lucky Pet Products Co., Ltd. , https://www.dgpetproduct.com
1. Ink stain test method GB/T 12911 test standard stipulation test method is currently the most widely used and simple test method, the specific process is as follows.
(1) Applying a standard ink absorbing ink to the surface of the paper to be inspected uniformly;
(2) Quickly erase the remaining ink on the surface of the paper with absorbent cotton after a specified time;
Apply whiteness meter (shown in Figure 1) to measure the whiteness of clean paper and dirty areas respectively, according to the formula "paper ink absorbability = (base paper whiteness - dirty area whiteness) / base paper whiteness × 100% ", you can get the ink absorption of the paper. The larger the value, the stronger the absorbency. 
Figure 1 Whiteness meter 
Figure 2 IGT tester
The specific impact on the printing process 1. Inconsistent ink absorption <br> Paper unevenness is mainly reflected in the uneven density of ink in the printed graphic area, as shown in Figure 3. In terms of paper, the main reason for this phenomenon is that during the papermaking process, due to the uneven distribution of fibers and coatings (coated paper), the density of pores in different areas of the paper is inconsistent, after calendering This kind of fluctuation will become more apparent afterwards. When the ink is transferred to the surface of the paper, the ink penetrates quickly in the region with more pores of the coating, and the ink penetration is slower in the region with less pores, resulting in inconsistent drying speed of the ink in different regions, affecting the transfer and overprinting of the ink, resulting in uneven ink density. Printed hair will appear when it is more serious, as shown in Figure 4. 
Figure 3 uneven ink absorption 
Figure 4 printing facquard