You know well about corrugated paper ? one
1. Quantitative. Quantitative, also known as weight, it refers to the weight per square meter of paper, with the G / m expressed. Quantitative formula is: area of sample weighing / sample. Quantitative is an important indicator of the physical properties of paper, in general, higher weight paper, its tensile strength, ring crush strength, tear, stiffness and thickness of the index is relatively high. Quantitative paper material with a high production of corrugated boxes, its compressive strength is comparatively higher. Therefore, to produce high-strength corrugated boxes, select a high quantity of paper stock, they tend to be one of the basic requirements of customers.
2. tightness. It refers to the weight per cubic centimeter of the paper, with the G / CM? To represent.
How tightness paper reflects the density of the extent of its fibrous tissue structures. Tightness value containerboard and corrugated high, their bursting strength, ring crush strength, puncture resistance and tensile properties of relatively good, then, the overall strength of the cartons also relatively high. However, if tight too large, paper easy to rattle, especially white paper, if the value of tightness significantly larger than the standard, and its performance will decline folding. So, with the white paper as a surface layer of corrugated cardboard pasting, not too high a tight white paper, so as not to affect the folding carton roll cover.
3. Central pressure strength. The standard sample length (longitudinal) 152 ± 0.2MM, width 12.7 ± 0.1MM, take 10 were detected, of which five were detected positive outward, the other five negative outward annular tray load detection, then by formula Conversions can be obtained ring crush strength of the base paper. Generally, produced with good paper cardboard ring crush strength is comparatively high.
Ring crush strength is calculated as: R = F / 152. Wherein R represents a ring crush strength, unit KN / M; F is the force value when the sample crushed read, unit N; 152 is the length of the sample, the unit MM. GB standard values in the ring crush index is an important indicator to measure the compressive strength of the base paper, it refers to the base paper ring crush strength and quantitative ratio, in the units N? M / G. The index is calculated as: RD = 1000R / W. RD formula represents ring crush index, R represents a ring crush strength, W is a quantitative test sample, G / m. Paper ring crush index of how greatly affects the overall strength of the carton, especially a greater impact on the compressive strength of the carton.
4. sizing degree. After the paper, cardboard production, exert a certain amount of rosin and other water resistance of colloidal material, so that the paper increase water resistance, this production process called sizing. Sizing is a measure of quality indicators glue size, according to national standards, it can be crossed and surface ink absorption gravimetric method for detection. Factories also be crude, with the "drip method" to detect the degree of sizing of paper. Its approach is: a little water drops on paper, if the bleeding fast drop, indicating the degree of sizing is not good. If the water drops less prone to bleeding phenomenon, indicating the degree of sizing like. Corrugated base paper production requires sizing degree is better, so easy to absorb moisture, the moisture content of stable cartons, can better ensure the strength of the carton.
5. moisture. The so-called moisture content means that the content of moisture in the paper or paperboard, expressed as a percentage. Three water content of carton box strength, has a great influence, so this is the moisture content of the main reasons to become a heavy carton of one item defect inspection. When the high moisture content of the carton, and its resistance to puncture, compressive strength and burst strength properties relative decline. Corrugated paper has a certain pressure, tensile, anti-puncture and folding properties, if the moisture content is too high, the paper becomes soft, very poor, press shocked and bonding quality is poor. If the water was significantly lower than the standard limit value, when the pressure is prone to cracking phenomenon flute. If the moisture content of corrugated and containerboard disparity is too large, single machined out of corrugated cardboard, is prone to curling, timely mounted next step, it is prone to blistering and degumming, significantly decreased the strength of the carton.
6. folding. Carton as a packaging container for open roll cover needs regular activity, which requires a paper material should have some folding capabilities. Lateral folding of the paper was to determine the paper in a certain tension, speed and angle conditions, the sample size of 150 × 15MM, for 135? Angle of the shuttle fold test, when the fracture pattern, that is, the degree of folding the frequency of inspection. Cardboard and paperboard manufacturing pulp properties, the moisture content of the paper, tightness, fiber length and cohesion fastness and paper storage time and temperature affected by other factors, to a large extent determines the base paper folding degrees. Therefore, to improve the performance of folding cartons, good quality control of raw materials is an important part.
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