Soft toilet paper making process

As a widely used daily necessities, toilet paper has attracted people's attention for its quality such as appearance, strength, and feel, especially softness. Production practice shows that to make high-grade, soft-textured toilet paper, in addition to having good mechanical equipment and reasonable production processes as guarantees, it is more important to adopt the correct production process and strict process control.

1. Appropriate ratio of long and short fibers is a prerequisite for the delivery of soft toilet paper. Long fiber pulp can give toilet paper enough strength, while short fiber pulp has a greater influence on the feel of hand, especially softness. Therefore, it is necessary to make high-grade sanitary napkins with good strength and softness, and the matching ratio between the length and the short fibers should be well matched. At present, domestic raw materials for toilet paper: long fibers are mainly imported bleached softwood pulp or domestic cotton pulp, short fiber imported or domestically produced bleached hardwood pulp, imported mixed waste paper or white paper edge of domestic printing plants, deinking waste Pulp (DIP). If pure pulp is used to produce toilet paper, the ratio of long and short fibers is 3:7 or 4:6. Of course, it is better to add a small amount of cotton pulp. If all waste paper or paper edges are used as raw materials, the sorting of waste papers from different sources should be strengthened. For example, 60% imported white waste paper can be matched with 40% domestic white paper, or 40% imported white paper can be matched with 30% DIP and 30% domestic white paper. The proportion of short-fiber white paper is controlled at 30% to 40%, and the same effect is good.

2. A good beating process is a guarantee for the production of soft toilet paper. For the papermaking of toilet paper, the pulping process must be strictly controlled because it uses raw materials of different fiber lengths as raw materials. In general, long fiber pulp must be beaten to give the toilet paper sufficient strength. The degree of beating can be controlled at 30 to 45” SR. Short fibers or waste pulp are mainly based on lyophylization, supplemented with mild cuts. , Its degree of beating can be controlled in 20 ~ 30 "SR. The degree of beating of the Internet paste is generally controlled at 28-40. SR. For some manufacturers, especially those who use whole waste paper as raw materials, it is generally not advisable to increase the degree of beating to make up or increase the strength.

In order to increase the degree of beating, on the one hand, the energy consumption increases. On the other hand, the speed of the drainage of the net portion decreases, the speed of copying decreases, the steam consumption increases, and the strength of the sheet is also disadvantageous. Therefore, it is advisable to use as much as possible a high-slurry, multi-series, light-knife beating process or a fully dissociative, de-sanding machine used in conjunction with a disc refiner.

3, the role of dispersant, softener can not be ignored in the Internet paste to add an appropriate dispersant, can significantly improve the degree of paper hook, to improve the softness and feel of the paper sheet. At present, most domestic manufacturers use imported PEOWF or domestic PEO as dispersants. The use of PEO should pay attention to the choice of its molecular weight (generally 3X106 or more), preparation method (preparation concentration and dissolution stirring speed), addition amount control (general 1.0 ~ 1.skg / t paper) and the impact of the production of water quality. In addition, some manufacturers, especially those who use full waste paper as their raw materials, have also added other softening agents to the pulp to further improve the softness, such as some stearic acid and mirinine softeners.

4. The correct start-up process is to copy the high-grade toilet paper, and the American Air Inc.'s offense is to peel off the paper sheet that clings to the surface of the dryer cylinder, and the paper sheet is slightly curled to generate wrinkles. It is the effect of wrinkling (damaging the hydrogen bonding between the fibers, changing the internal structure of the sheet), giving the toilet paper a good feel and softness, which is also the difference between toilet paper and general tissue paper. Therefore, the wrinkle process has a great influence on the softness and feel of toilet paper. The following is a set of better wrinkling process parameters: blade thickness 1.5 ~ 3. Omm, scraper blade angle 85 ~ 90 ", the angle between the blade and the dryer cylinder 18 ~ 25"; into the cylinder paper moisture about 65%, dryer temperature 115 ~ 120 °C; wrinkling paper sheet moisture 5% ~ 10 % (preferably 6% to 8%); wrinkle ratio 1.2 to 1.3 (wrinkling rate 25% to 30%). The above process parameters are suitable for the commonly used rotary screen machine, but for the high speed Guomiao machine or the long machine, it is necessary to make specific adjustments. With regard to the moisture content of the sheet entering the drying cylinder and the moisture during the creping, the former has a relationship with the sticking force of the supply cylinder, and the latter has a greater influence on the texture and texture of the formed sheet. The adhesion of the sheet to the dryer is particularly important for high-speed tissue machines. At present, high-speed tissue paper machines imported from abroad or in China have begun to use wrinkle additives on the surface of dryer cylinders to produce a peeling effect. On the one hand, they protect the surface of dryer cylinders, on the other hand, they act as a lubricant and assist in stripping. , To achieve the purpose of improving the speed of the paper to improve the feel and softness of paper. For the general rotary screen machine, the effect of the wrinkle aid has yet to be inspected for production (I have performed the test for the high speed paper machine for the general Guoji paper machine. The effect is not satisfactory).

In summary, through strict process control, proper fiber ratio, correct beating process, supplemented by superior dispersants and other additives, it is possible to reduce the amount of quantification, and to create high-quality toilet paper with soft texture and high strength. And the purpose of tissue paper.