Talking about the matters needing attention of paper storage and the simple detection method of its quality

For a printing company, I am afraid that there is no complete paper measuring instrument. When purchasing paper, it can only rely on the technical inspection report provided by the supplier. It is impossible to know whether the required quality requirements are met or whether it meets the technical inspection report provided by the supplier. . So, in this situation, how can we put a good quality mark on this batch of paper before entering the warehouse? According to the author's work experience over the past few years, it is concluded that paper should be tested at least from the following aspects.

1, must check the number of purchases, the actual number of payments, check whether the packaging has broken, broken situation, if there must be counted the number of small packages, and make a record of damage.

2. Carefully check the technical data and inspection report provided by it.

(1) Check whether each product has a factory certificate.

(2) Check whether there is an inspection report (preferably the original) provided by the Pulp and Paper Quality Supervision and Examination Center Station (site) where the supplier is located.

3, Randomly open one or two products, observe whether the appearance of cracks, wrinkles, curls and other issues, if such defects can be directly requested return, replacement.

4. Check its quality with simple operation methods.

(1) Test quantification: randomly select five or more proofs from the paper and cut them into 100mm*100mm four stacks (accurate to 0.1mm). Weigh the quality of each stack of papers with a balance and calculate whether the rations meet the requirements.

(2) Checking the folding endurance: Take out a few sheets of paper and hold a corner of a sheet and reciprocally fold 180 degrees (5-8 times). The minimum quality requirement is that there are no cracks or breaks in a few sheets of paper.

(3) Check the transparent point: Take 3-5 sheets of paper to catch the sunlight or bright light. If there is no special transparency of the film, point and line, then basically meet the quality requirements.

(4) Checking whiteness: Checking a few sheets of paper can be done by visually observing the whiteness of the front and back of the paper, comparing it with the standard sample left by the factory, and observing whether the whiteness of the paper meets the quality requirements.

(5) Check for bubbling and mildew: Take 3-5 random samples of paper, place it at a 45-degree angle to the ground, observe the natural light or take a magnifying glass, and ask for no signs of mildew and blisters.

(6) Check the flatness: Inspect the bubbling and mildewing methods, and then gently stroke the smoothness of the surface and carefully check the surface for streaks.

(7) Check whether there is powder (also a manual inspection method for the degree of squeegee and surface strength of the paper): Take a few samples, hold the corner of the paper, and scrape the same place with a fingernail to see if there is any paper powder. Out, the more paper powder falls out, indicating that the paper is worse (this method is more effective for checking glass cardboard).

(8) To test the water soaking method, lay the pattern on a glass plate, use a squirrel pen to cross the line at a speed of 10cm/s, and stay at the end of the line for about half a minute to see how the pattern penetrates the ink. Whether to meet the printing requirements.

(9) If there are no problems with the above items, all other items are also tested as qualified, indicating that the paper has reached the basic requirements for printing. At this time, a storage order should be completed and ready for classification in a dry, cool and ventilated place. Store. However, in the future when the machine is printing, if it is still unable to print properly due to the quality of the paper, it must rely on testing equipment to detect its accurate data, to see which of the items failed.