Introduction of the hottest Chinese carton perform

A brief introduction of China's carton performance testing standards (I)

the base paper used by China's carton manufacturers can be simply divided into imported base paper and domestic base paper if divided according to the origin; According to the variety of base paper, it can be divided into kraft paperboard (also known as Kraft linerboard in China), corrugated base paper, as well as whiteboard for higher-grade packaging and printing, coated kraft paper, coated kraft paperboard, etc. Due to the rapid development of China's carton industry, the demand for base paper is increasing year by year, especially coated kraft board. Because it not only has the advantages of kraft board and coated white board, but also has the strength of kraft board and the printability of white board, the import volume has increased significantly

although the overall quality of domestic base paper has been greatly improved in recent years, there is still a gap between the quality of domestic base paper and that of foreign base paper. Even if individual paper mills can reach the same level abroad, they cannot meet the demand for some kraft paper and corrugated paper with low gram weight and high strength due to limited production capacity. Most still rely on imports. For imported base paper, China's inspection and quarantine department has specific provisions: according to the provisions of the commodity inspection law, the commodities listed in the category list must be inspected by the inspection and quarantine institution or its designated inspection department, and shall not be sold and used without inspection. Most of the carton base paper imported from China is legally inspected goods, so it must be inspected. At present, the inspection standards followed by the inspection and quarantine department when inspecting these papers are roughly as follows:

1 Mandatory standards of laws and regulations or other inspection standards that must be implemented

2. If there are no mandatory standards or other inspection standards that must be implemented in laws and regulations, the inspection can be carried out according to the standards agreed in the contract between the two parties. (if the mandatory standards of laws and regulations are lower than the standards agreed in the contract, the standards agreed in the contract shall prevail)

3. Neither of the above two points can be inspected according to the standards of the producing country, relevant international standards or the standards designated by the national inspection and quarantine authority. If there is no suitable testing standard, the approved internal method standard shall be selected

here we need to make a special explanation for the above point 2. In our actual inspection process, we found that most domestic users do not have Shenwan Hongyuan in the quality terms of imported base paper in the trade contract. An analyst who did not want to be named told the reporter that there was enough agreement, or even no agreement. They often only recognize the brand and origin, and ignore the quality fluctuation of the product itself. In the first half of this year, our inspection and quarantine department inspected and found that there were several batches of imported paper with quality problems. However, due to the customer's failure to agree on the quality requirements and inspection standards for the receipt in advance in the contract, it was difficult for the inspection and quarantine department to issue the certificate of non conformance, and it was troublesome for the customer to claim for compensation and return. Therefore, we call on the enterprises importing base paper to agree on the quality terms in the contract, To protect their own income

the specific inspection contents of paper include: safety, health, environmental protection, quality, quantity, weight, packaging and other items. Due to space constraints, we will only introduce the conventional physical testing items and the methods and standards used

1. Appearance inspection: the appearance inspection of paper is one of the important inspection items. Generally, the domestic 3-yuan material market range is 7.98 billion yuan, and the on-site sampling inspection 1 is the high energy consumption per unit output value; 2. Limited oil resources; 3. Waste high molecular materials are difficult to degrade naturally and are composed of laboratory tests. The appearance defects of paper not only affect the appearance of paper, but also affect the use of paper. The inspection methods and standards we adopt are: ISO, TAPPI standards, sn/t and national standard gb/t1541 dust detection, etc. It mainly adopts light exposure test, head up test, squint test and hand touch test. The paper surface shall be flat and clean, and no folding is allowed

2. Physical property inspection: before carrying out physical property inspection, the paper must be pretreated with constant temperature and humidity according to the standards. Because different papers need different test items, here are mainly several:

(1) good white board paper generally requires tight texture, smooth surface, consistent thickness, non fuzzing, good absorption and small expansion rate, And can adapt to the requirements of multicolor overprint

in order to meet the requirements of box making, whiteboard should also have the characteristics of large stiffness and good folding resistance. The main importing countries are South Korea, Indonesia, the United States, Japan and so on, especially the quality of Japanese white board. The test items include: ration, thickness, whiteness, smoothness, fracture length, bursting strength, folding strength, sizing strength, stiffness, IGT, etc

(2) Kraft linerboard: Kraft linerboard, known as carton board in China, is one of the main types of carton paper. Domestic carton board paper is divided into three grades: excellent products, first-class products and qualified products. Kraft paper must be tough, with high burst resistance, ring crush strength and tear resistance, as well as high water resistance. Due to different processes and materials, in general, the quality of most imported kraft linerboard is better than that of domestic Kraft linerboard, especially the quality of American Kraft linerboard. The test items include: ration, thickness, tightness, bursting strength, bursting index, annular compression strength, transverse annular compression index, fracture length, tearing degree, sizing degree, moisture, quantitative difference of horizontal banner, transverse folding resistance, etc

(3) the test items of coated kraft linerboard and coated kraft linerboard are reference Kraft linerboard and whiteboard

(4) corrugated base paper: corrugated base paper is one of the important constituent materials in the production of corrugated board. Corrugated base paper requires good fiber bonding strength, flat paper surface, good tightness and stiffness, and a certain degree of elasticity, so as to ensure that the made carton has shockproof and pressure resistance. In addition, the moisture index should be controlled. If the moisture is too small, the paper will have a long and brittle service life, and it will break during Corrugated processing; Excessive moisture and soft paper will bring difficulties to processing and molding. Generally, the moisture content of paper should be controlled at about 10%. Domestic corrugated base paper is divided into four grades: A, B, C and D. The test items include ration, thickness, tightness, burst resistance, annular compression strength, transverse annular compression index, flat compression strength, fracture length, sizing degree, moisture, etc