What is the liquid absorption capacity? What are the main factors affecting the absorption capacity of the wipes?
1. What is the liquid absorption capacity?
Generally speaking, it includes two aspects of lateral water absorption speed and saturated water absorption capacity. The lateral water absorption speed refers to the height of the liquid spreading along the paper in a certain time. Saturated water absorption capacity refers to the multiple of liquid that can be absorbed per unit mass of paper. As a highly absorbent product, dust-free paper is widely used in the field of sanitary absorbent materials, such as the absorbent core of sanitary napkins, watch pads, sanitary napkins, and diapers. Therefore, the liquid absorption capacity of the product has aroused great concern. For saturated water absorption capacity, the current adhesive paper can reach 7-9 times, heat seal paper can reach 15 times, without SAP.
2. What are the main factors affecting the absorption capacity of the wiper paper?
(1) Fluff pulp factor: The longer and thicker the fluff pulp fibers, the higher the volume, liquid absorption capacity and absorption speed of the final product. The higher the fibrosis degree of the fluff pulp, the lower the fine fiber content, and the stronger the liquid absorption capacity. If the content of fine fibers and fiber knots is too high, the liquid absorption capacity and speed will be seriously affected. In addition, due to the different raw materials, pulping methods and treatment degree of fluff pulp, the liquid absorption performance is also very different. In general, the absorption performance of sulfate pulp is better than that of sulfite pulp. Coniferous wood pulp has better liquid absorption properties than hardwood wood pulp. The liquid absorption performance of untreated pulp is better than that of treated pulp (due to the addition of chemical treatment agents such as softeners and fillers, the content of extract increases and the liquid absorption capacity decreases).
(2) Adhesive factors: Generally, latex with good hydrophilicity is selected, and the product has good absorption. If you choose a hydrophobic latex, the paper may not absorb water. In addition, the greater the amount of latex, the worse the absorption capacity of the product.
(3) In order to obtain good absorption, the hot-pressing pressure must be appropriately reduced to make the paper as fluffy as possible and increase the liquid absorption space.
(4) For hot-melt paper, the melting and bonding of hot-melt fibers will seriously affect the liquid absorption performance. Therefore, the thickness and volume of the product should be increased as much as possible.
In glued paper, the greater the liquid absorption capacity, the faster the horizontal absorption speed; in heat-sealed paper, the vertical absorption speed of the paper (z direction) is faster, and the horizontal absorption speed (x, y direction) is slower, which may Because there are many hot-melt fiber nodes in the heat seal paper, especially in the z direction, there are many bonds, so the diffusion speed is low. The latex particles in the glued paper are mainly attached in the X and Y directions, while there is almost no adhesion of the latex particles in the Z direction, which makes diffusion easier.
