How to judge the quality index of the adhesive to improve the bonding strength of corrugated cardboard valentines day box chocolates
The adhesive strength of corrugated cardboard mainly depends on the quality of the adhesive and the sizing quality of the corrugated cardboard production line.valentines day box of chocolates
Adhesive quality valonia chocolate box
The quality of the adhesive mainly depends on the pros and cons of the adhesive manufacturing process and the quality of the raw materials used. The main raw material used in the adhesive is starch, and cornstarch above the industrial grade is generally used. If lower-grade starch is used, due to its poor processing fineness and more impurities such as protein and fat, it will consume more caustic soda, making the adhesive unstable, and the bonded corrugated cardboard is easy to absorb moisture, and the adhesive It is easy to produce gel with larger starch granules and impurities as the core, which makes the fluidity worse. walmart boxed chocolates
Solid content, initial tack, viscosity, pasting temperature, etc. are important indicators to measure the quality of adhesives: 36 piece godiva chocolate box
1. Solid content amazon chocolate gift box
The solid content of the adhesive should be determined according to the accuracy of the equipment, the running speed and the actual situation of the base paper. Once the speed of the high-speed wide-width corrugated board production line reaches 200 m/min or more, the solid content of the adhesive must be high. Water and starch The ratio is usually between 2.5:1-3:1. The higher the solid content of the adhesive, the less moisture it will be. A small amount of glue can ensure the adhesion of corrugated cardboard; and the change of moisture in the process of corrugated cardboard processing is small, which can reduce the warping of corrugated cardboard. If the precision of the enterprise’s equipment is low, the speed of the vehicle is slow, and the base paper is easy to see through, the solid content of the adhesive should be lower, otherwise it will cause quality problems such as degumming of corrugated cardboard, crystallization of paste lines, and bursting of lines. best box chocolates
2. initial tack best chocolate box for gift
Initial tack is the key to ensuring the adhesion of corrugated cardboard and increasing the speed of the machine. In the production of corrugated cardboard, increasing the preheating area of the base paper, or adding a crosslinking agent when making the adhesive, adding borax to the main body and the carrier tank respectively, and increasing the solid content of the adhesive can make the adhesive coated After a short period of time, it begins to produce adhesive force, and its adhesive force can destroy the paper fibers. best chocolate box for valentines
3. viscosity best gift chocolate box
The lower the viscosity of the adhesive, the better the flow. The fluidity of the adhesive determines the permeability of the adhesive, the uniformity of gluing and the amount of glue, which directly affects the speed of the machine, the adhesion of the cardboard, the flatness and strength of the cardboard. In addition, it is not that the higher the proportion of starch in the adhesive, the worse the fluidity; the adhesive with high solid content can also maintain a very low viscosity by adjusting the preparation process. Under normal circumstances, the viscosity of the adhesive will decrease every time it passes through the circulation pump during circulation. At this time, it should be mixed with the newly made adhesive.
4. gelatinization temperature
The gelatinization temperature refers to the initial temperature required to turn the starch binder into a paste. The gelatinization temperature of the binder is a key factor to maintain high-speed production. To solve the problem of the gelatinization temperature of the binder, in addition to adjusting the caustic soda In addition to the dosage and heating method, the same effect can also be achieved by adding some additives appropriately. The gelatinization temperature should not be too low, otherwise it will cause the gelatinization of the adhesive during circulation and affect the fluidity of the adhesive. The gelatinization temperature of the adhesive should be adjusted according to seasonal changes. In winter, the gelatinization temperature can be lowered to 55-60°C, and in summer, the gelatinization temperature can be adjusted to 61°C-66°C.
Sizing quality of corrugated cardboard production line
In Europe and the United States, the most important inspection of the quality of corrugated boxes is the inspection of the width of the glue line of the corrugated board. The standard sizing is that the position is accurate, the adhesive is applied evenly and smoothly on the entire flute, the glue line is clearly outlined, and there is no lateral projection of the adhesive from the corrugation, and no dragging glue traces.
Poor sizing is mainly related to the equipment status of the corrugated board production line, the quality of the adhesive, and the quality of the base paper.
Common quality problems caused by poor sizing are mainly manifested in the following aspects:
1. Drip glue phenomenon
There is dirt on the top roller, such as paper scraps, starch agglomerates and other foreign matter, or there is foreign matter clogging the cells on the surface of the roller, so that the top roller cannot be glued smoothly, and only a small amount of adhesive can be transferred, and it is easy to be wiped Falling, when gluing, there will be insufficient gluing on the corrugated peak, and there will be intermittent dripping of gluing. There will be traces of delamination between the surface paper and the core paper on the surface of such corrugated cardboard, and the compressive strength, edge compressive strength and adhesive strength of the carton will all be reduced.
When the gap between the upper rubber roller and the lower corrugating roller is too wide, the upper rubber roller cannot touch the lower corrugating roller, and there is not enough adhesive on the corrugated peak.
2. Adhesive Transversal Projection Phenomenon
If the viscosity of the adhesive is too high; if it is too low or the content of borax in it is too high, it is easy to cause the adhesive to shoot laterally when the production line is running at high speed, which will cause the cardboard to warp or become soft, and the bonding and side pressure of the carton and compressive strength will decrease.
Post time: Jul-19-2023
