Light calcium carbonate is one of the important raw materials for the production of cigarette paperIts characteristics directly affect the quality of cigarette paper. The addition of high-quality light calcium carbonate can give cigarette paper higher breathability, opacity, uniform and delicate appearance, good combustion performance and strength, breathability coefficient of variation is small, to meet the needs of tobacco factory to reduce coke, reduce harm and high-speed cigarettes. After the cigarette does not show the bottom, does not go out, the bag gray good and whiteness high.
Practice shows that in the production of high-grade cigarette paper, the light calcium carbonate as a filler is required to have a relatively complete spindle-shaped crystal shape, uniform and neat grains, the particle size is mainly distributed at about 1-2μm, there is no large particle size (>5μm), and the dispersion and combination performance in the pulp is good.
1. Basic characteristics of light calcium carbonate for cigarette paper
As an inorganic powder material for papermaking, the inherent comprehensive factors of the performance of light calcium carbonate mainly include four aspects: powder micro-physical structure characteristics; micro-morphological characteristics; physical characteristics, such as whiteness, particle size distribution, rheology, abrasion, adsorption, optical and electrical conductivity; chemical characteristics, such as chemical composition.
Among them, cigarette paper with light calcium carbonate.Crystal morphology, particle size and distribution uniformity and surface shapeIt has a great influence on its performance and application range, and is also an important factor affecting the quality of cigarette paper and cigarette performance.
2. Morphological characteristics of light calcium carbonate for cigarette paper
The analysis of light calcium carbonate for cigarette paper at home and abroad shows that there are many particle forms of light calcium carbonate products, and the most basic particle forms of cigarette paper filler are spindle-like, chrysanthemum-like and needle-like. In order to meet the requirements of high breathability and high-strength cigarette paper, the light calcium carbonate used as filler needs to have.more apical spindle-shaped crystalWhen the filler used in cigarette paper is combined with the fiber, it is easy to form more cavities, produce bridging effect, make the fiber shed and form uniform pores. The morphological particles can improve the permeability, thickness, opacity and stiffness of the paper while minimizing the strength of the paper sheet, reduce the difference between the two sides and obtain high filler retention rate between the interwoven fibers.
3. Physical properties of light calcium carbonate for cigarette paper
The surface of light calcium carbonate has fine pores, which can give it larger porosity and specific surface area, high oil absorption value and astigmatism coefficient. Good quality of light calcium carbonate micro pore size is small, uniform, high porosity; in the cigarette paper application characteristics mainly in the paper thickness, opacity and so on.
Although different crystal forms of light calcium carbonate have a greater impact on paper quality, but even the same form of light calcium carbonate due to particle size uniformity, single crystal integrity and the degree of regularity (degree of order) differences will also have a certain impact on paper quality. Fillers with too much content of fine particles or large particles (I. e., poor particle size uniformity) sometimes affect the uniform distribution of fillers in the paper fibers. Especially in the case of high-speed paper machine dewatering negative pressure, the uneven distribution of large particles and fine particles that are prone to flocculation in the y and z direction of the paper is one of the reasons for the large difference between the two sides of the paper,Narrow particle size distribution is considered to be one of the important characteristics of light calcium carbonate for cigarette paper.
4. Raw material requirements of light calcium carbonate for cigarette paper
Light calcium carbonate should be able to meet the requirements of the cigarette paper industry for the control of heavy metal ions Pb, toxic elements As, the total number of colonies and fluorescence and other health indicators. Therefore, the production enterprises in the selection of limestone raw materials, coal and production water should be strict requirements.