Double-layer composite filter paper and preparation method thereof

Abstract

The invention provides a double-layer composite filter paper and a preparation method thereof. The double-layer composite filter paper comprises an outflow layer and an inflow layer which are combinedtogether, wherein the outflow layer and the inflow layer are impregnated with a resin material; the slurry of each of the outflow layer and the inflow layer consists of hardwood pulp, dried softwoodpulp and softwood pulp; the average pore size of the outflow layer is 15.1-18.5 [mu]m; and the average pore size of the inflow layer is 18.8-23.8 [mu]m. The double-layer composite filter paper has high filtration precision, high filtration efficiency, and good mechanical properties and high temperature resistance; and raw materials used for the preparation of the paper are all wood fibers, and arecheap and easily available.

Description

technical field [0001] The invention belongs to the technical field of filter paper manufacture, and in particular relates to a double-layer composite filter paper and a preparation method thereof. Background technique [0002] Filter paper is a kind of porous material made of plant fiber and wet forming technology. It is widely used in many fields such as machinery, medical treatment, automobile, food, military, environmental protection and safety quality inspection. It is a very common filter medium. . In the automobile industry, automobile filter paper is one of the main materials for the production of automobile filters, including air filter paper, oil filter paper, and fuel filter paper, which are used to remove impurities in air, engine oil, and fuel oil, prevent engine parts from wearing out, and prolong their use. The performance of the filter paper has an important relationship with the economic and technical indicators, environmental protection indicators, safety ...

AI Technical Summary

Problems solved by technology

Most of the existing automotive filter papers are homogeneous structure filter papers, which are macro-homogeneous materials, and it is almost impossible to balance the filtration accuracy and filtration resistance by adjusting the pore size.

Gradient structure filter paper refers to the preparation of different types or different diameters of fiber raw materials into a filter material with a layered structure with continuous distribution of pore sizes in the cross-sectional direction, which is conducive to small-scale and stage-by-stage adjustment of filtration efficiency and filtration resistance. The parameters of the relationship make the filter paper fully exert the filtering effect of each layer of fiber raw materials and achieve a more ideal separation effect. The Chinese patent literature with the publication number CN102154954B discloses a kind of air filter paper suitable for desert areas and its preparation method. The larger upper layer and the lower layer with smaller pore size are composed of two wood fiber layers directly compounded by adsorption and impregnated with resin, which can improve the filtration accuracy and efficiency at the same time. This filter paper is suitable for car air filter paper in desert areas, but for oil filter paper or fuel filter paper , due to the high dynamic pressure at the start of the internal combustion engine and the high temperature during operation, the filter paper needs to have better mechanical properties and temperature resistance