Note: quantification of standard G; Standard T thickness

* either ring compression strength or short distance compression, as long as the corresponding index requirements can be judged as qualified.

3.1.3 the quantity (G) and thickness (T) of lunch box paperboard are determined by the manufacturer according to the usage requirements, which are required to meet the deviation requirements in this standard.

3.1.4 the size of the lunch box paperboard shall be determined according to GB/T 451.1 and shall meet the following requirements: 787 mm '1092 mm; 880 mm '1 230 mm. The size deviation shall not exceed ± 5 mm and the deviation shall not exceed 3 mm. According to the requirements of the contract, we can also produce other sizes of paperboard.

3.1.5 paper lunch boxes processed and formed by cardboard shall be made of paper lunch boxes meeting the requirements in table 1. Paper lunch boxes made by pulp molding and folding shall meet the requirements in table 2.

Table 2.

3.2 Health indicators 3.2.1 The paperboard and paper lunch box should comply with the physical and chemical indexes in table 3 and the microbial indexes in table 4. Table 3

Note: according to the method stipulated in GB/T 7974, Rf≤2.0 shall be used for arbitration. Table 4

Note: * either of the two, as long as the corresponding target requirements can be qualified.

Marking, packaging, transportation and storage

5.1 the packaging and marking of the cardboard and paper lunch box shall be carried out in accordance with GB/T 10342. Usually, there shall be two layers of packaging inside and outside the lunch box. The packaging shall be neat and the quantity shall be accurate, or shall be carried out according to the requirements of the order contract.

5.1.1 the inner packing materials must be clean, non-toxic, odorless, dustproof and waterproof. The inner packing boxes should be attached with explanatory labels, indicating the following contents:

A) product name, type, registered trademark, production license and hygiene license number;

B) name of the manufacturer, place of origin, batch number or production date and validity period;

C) inspection mark and standard code.

5.2 the cardboard and paper lunch boxes should be properly kept to prevent rain, snow and ground moisture.

5.3 during transportation and storage, the relevant units shall strictly prevent the pollution of toxic drugs and heavy metal dust.

5.4 the shelf life of unsealed bulk products shall not exceed 1 year. The overdue products shall be re-inspected according to the requirements of (3.2), and can only be used if they meet the standards.

Appendix A - determination of the serviceability of paper meal boxes (standard appendix)

A1 volumetric determination

At room temperature, use a measuring cylinder of 1 000 mL, measure the corresponding volume of water and pour it into the paper lunch box. The large lunch box is 600 mL, the medium size lunch box is 500 mL, and the small size lunch box is 400 mL.

A2 water resistance test

Put the paper lunch box flat on the board (or pulp board), pour the NaCl water with the temperature of (90± 5)℃ and the concentration of about 5%, and add 1 to 2 drops of methyl red indicating liquid, the height should not be lower than 20 mm. 1 h later, pour out the water and observe whether there are leakage marks on the back and both sides. If no leakage marks are found, it will be qualified; otherwise, it will be unqualified.

Oil resistance test for A3

Put (150± 10)℃ edible oil (peanut oil, soybean oil), add (10± 2) mL with a porcelain spoon into the paper lunch box, then put the paper lunch box on a napkin. Observe whether there is any oil on the napkin after 1 hour. If there is no oil, it is qualified; otherwise, it is unqualified.

A4 load bearing performance test

Place the paper lunch box on a flat plate and cover the lid. Measure the height of the paper lunch box (with cover) with a metal ruler, accurate to 1 mm. Then pour in the slurry mixture. After the lid is closed, place a piece of 200 mm '200 mm' 3mm flat glass on top. Then place the 3 kg weight in the center of the plate glass, and immediately remove the weight and the glass plate when the load is 15 s, and then measure the above height accurately. The following formula is used to calculate the load-bearing performance value of the sample: