Paper towel inspection

Paper towels are daily disposable products used for wiping and cleaning, and are widely used in home, office, catering, travel and other scenarios. Common paper towels include facial tissue, napkins, tissue paper, wet wipes, etc., which vary slightly in material, softness and water absorption according to different uses. High-quality paper towels are usually made of virgin wood pulp, bamboo pulp or mixed pulp, and are made through high-temperature sterilization and dust-free processing. They are soft in texture, highly absorbent, do not contain fluorescent brighteners, are non-irritating to the skin, and are suitable for infants and sensitive people. The production process of paper towels must comply with national health standards, and some high-end products also have environmental protection functions such as antibacterial, dust-free, and degradable. The packaging is diverse and easy to carry and use, and is an indispensable cleaning product in modern people's lives. With the improvement of consumers' awareness of health and environmental protection, high-quality, natural and safe paper towel products are becoming increasingly popular.

Classification

Paper towels are divided into paper facial towels (facial tissues), paper napkins (serviettes) and paper handkerchiefs (handkerchiefs) according to their uses.

Paper towels are divided into virgin wood pulp (fiber) paper towels, virgin non-wood pulp (fiber) paper towels and virgin mixed pulp (fiber) paper towels according to their raw materials.

Note 1: Virgin wood pulp (fiber) tissue refers to tissue whose fiber raw material is 100% virgin wood pulp (fiber).

Note 2: Virgin non-wood pulp (fiber) (such as straw pulp, bamboo pulp, bagasse pulp, etc.) paper towels refer to paper towels whose fiber raw materials are 100% virgin non-wood pulp (fiber).

Note 3: Virgin mixed pulp (fiber) tissue refers to tissue produced by mixing virgin wood pulp (fiber) and virgin non-wood pulp (fiber).

According to product performance, paper towels are divided into ordinary paper towels, soft paper towels, wet-strength paper towels, dispersible paper towels and moisturizing paper towels. Among them, ordinary paper towels are further divided into superior products and qualified products.

Note: Moisturizing paper towels refer to paper towels with a certain amount of moisturizing ingredients added and a soft and smooth surface.

Paper towels are divided into single-ply, double-ply and multi-ply according to the number of layers.

Tissue paper is divided into white tissue paper, natural tissue paper and colored tissue paper according to its color. Among them, colored tissue paper is further divided into printed tissue paper and dyed tissue paper.

Paper towels are divided into embossed paper towels and non-embossed paper towels according to the craftsmanship.

raw materials

Paper towels should use non-toxic and harmless raw materials, and water-based ink should be used for printing. Paper towels should use virgin fiber materials such as wood, grass, bamboo, etc., and should not use any recycled paper, paper printing, paper products and other recycled fiber materials as raw materials, and should not use deinking agents.

If flavors are added during the production of paper towels, the flavors used should comply with the provisions of GB/T22731. If moisturizing ingredients are added during the production of paper towels, it should be ensured that the added moisturizing ingredients comply with the provisions of the "Technical Specifications for Safety of Cosmetics" (2015 edition).

The safety evaluation and management of chemicals and raw materials used in tissue base paper should comply with the relevant provisions of GB/T36420.

Require

Physical and chemical performance requirements

The physical and chemical properties of paper towels need to meet the requirements

Hygiene requirements

The hygiene requirements for paper towels should comply with the provisions of GB15979.

Shortage of internal volume

When the internal quantity is less than or equal to 50 sheets (drawn), there should be no shortage; when the internal quantity is greater than 50 sheets (drawn), the shortage should be less than or equal to the internal quantity × 1%, and the result is rounded to an integer. If a decimal occurs, it should be rounded up to the next integer.

Dimensional deviation

Paper towels are generally flat or flat-cut and folded, and the size deviation should not exceed ±5mm.

Appearance quality

The paper towel should be clean and have even wrinkles. There should be no obvious dead folds, defects, damage, foreign matter, hard lumps, pulp lumps and other paper defects.

Test methods

Sample collection and processing

The sampling of samples shall be carried out in accordance with GB/T450.

When determining the quantitative value and quantitative deviation, transverse liquid absorption height, transverse tensile strength, longitudinal wet tensile strength, softness, powder loss rate and dimensional deviation, the sample processing and the standard atmospheric conditions of the test shall be carried out in accordance with the provisions of GB/T10739.

Quantification and quantitative deviation

The quantitative quantity and quantitative deviation are determined according to GB/T24328.5, and the results are expressed in single layers.

D65 Brightness

D65 brightness is measured according to GB/T7974.

Migratable fluorescent substances

Place a stack of samples (thick enough to be opaque) and a fluorescent standard sample (fluorescent brightness of 0.40%~0.60%) under a UV lamp with a wavelength of 254nm and 365nm at a distance of about 20cm, and compare and observe the fluorescence phenomenon of both sides of the sample and the fluorescent standard sample. If the fluorescence phenomenon of the sample is weaker than that of the fluorescent standard sample, the test is terminated and the test result is reported as no migratable fluorescent substance; if the fluorescence phenomenon of the sample is stronger than that of the fluorescent standard sample, the migratable fluorescent substance determination is carried out according to Chapter 5 of GB/T27741-2018.

Ash

The ash content is determined according to GB/T742, and the ignition temperature is (575±25)℃.

Horizontal suction height

The horizontal liquid absorption height is measured according to GB/T461.1, the test time is 100s, and it is measured according to the number of finished product layers.

Transverse tensile strength

The transverse tensile strength is measured according to GB/T24328.3. The width of the specimen is 15 mm, the clamp distance is 100 mm, and the single-layer, double-layer or multi-layer specimens are measured according to the number of layers of the finished product.

Note: If the sample length cannot meet the test requirements of 100mm clamp distance, use 50mm clamp distance for testing.

Longitudinal wet tensile strength

Manual method

Determined according to GB/T465.2. The width of the sample is 15mm, the clamp distance is set to 100mm, and it is determined according to the number of finished product layers. Pretreatment should be carried out before testing. The sample should be placed in an oven at (105±2)℃ for 15min. After taking it out, it should be balanced under the atmospheric conditions specified in GB/T10739 for at least 1h before testing. During the test, the sample is clamped on the horizontal tensile machine to keep the sample straight but not under force. Use a rubber-tipped dropper to continuously drip two drops of water (two drops totaling about 0.1mL) to the center of the sample. The outlet of the rubber-tipped dropper is about 1cm vertically away from the sample. Start timing while dripping water. After 5s, use three layers of 102-medium-speed qualitative filter paper (four layers of qualitative filter paper for single-layer samples) to touch the bottom of the sample for 3s~4s to absorb excess moisture on the surface of the sample. The qualitative filter paper cannot be reused. Start the tensile machine immediately after absorbing dryness. The entire operation (dripping water to the end of the tensile test) should be completed within 35s (of which the stretching time is not less than 5s). Take 10 valid test values, calculate their average value, and express the result as the test value of the finished product layer.

Automatic method

The test is carried out according to the horizontal test method in GB/T24328.4-2020, and the results are expressed as the test value of the finished product layer. An automatic immersion tensile tester is used, and the sample immersion time is 5s.

Softness

The softness is measured according to GB/T8942. The width of the instrument slit is set to 5mm and the sample is cut into 100mm×100mm.

If the sample size does not reach 100mm, convert it to 100mm and report the result. Paper towels are tested according to the finished product layer. Whether it is embossed or non-embossed samples, they should be uncovered and overlapped for measurement. At least 6 samples of the same sample should be measured in the vertical and horizontal directions, and the test results are reported as the average value of the vertical and horizontal directions. For folded samples, try to avoid the folded parts when cutting and testing. However, if there is a conflict between ensuring the sample size and avoiding creases, priority should be given to ensuring the sample size. For embossed products, if the embossed part cannot be avoided within the sampling area (100mm×100mm), the product does not need to be tested for softness. If it can be avoided, the embossed part must be avoided for testing. However, for soft tissues and moisturizing tissues, regardless of whether the embossed part can be avoided within the sampling area, the softness must be measured. If the embossed sample cannot be layered, it can be directly tested without layering.

Hole

Hold the two corners of the single-layer sample with both hands and observe against the light, and count the number of holes within the specified range. For double-layer or multi-layer samples, measure each layer. The test area of ​​each sample should not be less than 0.5m2, and then convert it into the number of holes per square meter. If holes larger than 5mm appear, the test area should not be less than 1m2.

Dust

Dust density is measured according to GB/T1541. For double-layer or multi-layer samples, only the upper and lower surfaces facing outward are measured, and the test area of ​​each sample (the total area of ​​the upper and lower surfaces) should not be less than 0.5m2; for single-layer samples, both the front and back sides are measured, and the test area of ​​each sample (the front and back areas should be included) should not be less than 0.5m2.

Shortage of internal volume

The shortage of internal quantity is determined by counting method. When testing, the outer packaging should be removed and the number should be counted visually. Three complete packages should be tested for each sample, and the result is expressed as the maximum shortage.

Dimensional deviation

Take 10 specimens from any package, measure the length and width of each specimen with a steel ruler with a graduation value of 1 mm, and calculate the average value respectively. The dimensional deviation is expressed by subtracting the nominal value from the average value, and the result is rounded to the integer.

Appearance quality

The appearance quality is inspected visually.