Viscose quality is the key to improving the quality of the carton. However, despite the great importance I attach to actual production, we must be cautious, and no matter how smart you are, it is still very difficult to avoid the existence of inferior glue and waste glue.
The use of inferior glue liquids directly for production will inevitably reduce the quality of the finished product box and even cause serious waste. The waste glue liquid obviously cannot be used for production, but it is a pity to give up.
Can we find a remedy and re-use measure? Our company “dare to eat crabs†in the production practice, continuously explored, and finally made a “rejuvenation†and benefited greatly.
To cure a serohide, you have to diagnose the condition and analyze the cause. First of all, we should understand the characteristics and causes of inferior glue and waste glue.
The characteristics of inferior glue:
First, the glue is thin, there is a slight precipitation, there is no sense of smoothness in the hands, picking sticks with sticks is not sticky, and there are a large number of powdery precipitates in the rubber pan when serious. For production, the glue amount is adjusted to the maximum and the glue is not applied. Even if the glue can be coated, the moisture in the glue quickly penetrates into the base paper, leaving only the starch of the track, the cardboard shows poor adhesion, and the large-area open glue. .
Second, there are solids in the glue. Generally, the mother liquor is too thick, and the starch liquid is injected into the starch solution too quickly. The stirring time is short, or the borax cake is not fully opened. There is also an impure plastic can, and the glue on the tank wall falls off or is misplaced in other insolubles. During production, foreign matter is sandwiched between the rubberizing roller and the control roller, which controls the amount of glue. The scratches appear on the rubber coating roller. When the adhesive roller is coated, the adhesive is uneven. When the weight is small, there is no glue at the scratch, resulting in a longitudinal stripe without tape. , The cardboard produced by the local drum open plastic.
Third, the glue concentration is too high, the vertical roller does not fall, and there is tofu brain-like agglomeration. When used in production, the liquid roller is inflexible and even difficult to rotate. The rubber roller is uneven, and the cardboard is one side with a large rubber side. The speed of the dryer speeded up, and the cardboard on one side of the plastic was excessively damp, resulting in sticky tiles; the speed of the dryer was a little slower, and the cardboard on the small side of the glue dries quickly, that is, there are quality accidents such as cardboard cracking, degumming, and indentation cracking.
Waste glue characteristics:
First, there is yellow water on the upper layer, which proves that the starch precipitates and the glue liquid fails.
Second, there are a large number of bubbles floating in the upper layer of glue, no precipitation, yellow glue, accompanied by a pungent odor, indicating that the glue has spoilage.
The reasons for the above symptoms:
Bad formula
2. Poor production process;
3. Operational errors;
4. The glue liquid and the equipment are not clean;
5. Failed to flexibly add or remove caustic soda or borax based on the environment's temperature and humidity and production base paper;
6. The stirring time in glue production process is short or long;
7. The higher the glue concentration, the greater the misunderstanding of the bond strength.
8. Failed to make proper amount of glue according to the amount of production.
9. The glue liquid was placed for a long time. For some reason (such as equipment failure, power failure, gum supply, etc.), it was not used in production in time.
In addition to taking corresponding measures to minimize the formation of inferior glue and waste glue, we have timely remedied and reused existing inferior and waste glues:
First, thin glue can be injected 100-300kg of mother liquor per ton (starch: water: caustic = 25:300:3) until the gum liquid is no obvious mother liquid colloid, and mix well.
Second, the solids of the glue liquid filtration (with 60 mesh mesh).
Third, the concentration of the glue is too high according to the actual situation into the tap water, stir with a mixer (600 ~ 800 rev / min) until the use of sticks to pick up glue can free fall, drawing 2 ~ 3cm is appropriate; or add tons of plastic 3 to 10 kg of CO(NH2)2 can be stirred for 20 minutes (800 rpm).
Fourth, there is yellow water in the waste glue can be added 1 ~ 2% of the emulsifier CCL4 fully stirred, and then add waste rubber volume 1/3 of the new glue and stir.
Fifth, there is bubble corruption of glue, add 40% formaldehyde 1kg per ton, then add 8000ppm white latex 20kg, and then inject 2/3 of the new plastic glue to start mixing evenly.
The glue solution treated by the above method must be used up on the same day. If it is used for some reason, it can be injected into 40% formaldehyde in a proportion of 5kg per ton of glue to fully mix and prevent deterioration. (Shan Xiaojing)