Sealing compounds are sealants used in metal containers to prevent leaks along the seams. between the container and the lid If it’s a 3-piece can, rubber sealant will be used on both the bottom and top lids after packing food or goods into the container to prevent contamination from outside. This extends the shelf life of the product inside the can.
In addition, this canister sealant has to withstand high temperatures in the sterilization process to preserve food quality for food cans. At present, there are 2 types of cans sealant as follows:
1. Rubber sealant that relies on water as a base material.(water base sealing compounds) It is a rubber that is produced accordingly. International Food and Drug Administration (FDA) standards for use with food containers. which has advantages such as being environmentally friendly, non-toxic to consumers There are different types of sealant depending on the application and the products packed in cans as each product requires different waterproofing, such as food cans, beverage cans, etc. Common cans are oil cans. machine aerosol can Medicine or cosmetic tubes, etc.
2. Rubber sealant based on polyvinyl chloride as a base material (PVC Plastisol) is used for sealing other metal containers from 20 liter containers (Crimp Cap) up to 200 liters such as gallon bucket for paint tanks for filling oil, etc. This is also used for non-metallic packaging such as crown caps of soda bottles. Screw cap sealant (RO) or twisted-off cap (ROPP) of energy drink bottles and rubber sealant Lug Cap or Twist-Off of jam bottle caps
However, the property of the two types of sealant is to maintain the quality of the products contained within the container by Prevent contaminants from the environment internal gas composition retention Preserving the smell and color of the packaged products as well as the taste so that they do not change.
Figure A. Before application of sealant Figure B. Figure C. After application of sealant, cap (top) and cap (bottom)
put grout in grooves (fictitious figure) at the edge of the cap.
The figure above shows a cross-sectional view of a can lid. Figure A shows a coated metal sheet. and molded into a lid including the curvature of the cap corner. Figures B. and C. show the picture of applying sealant to the cap along the inner curved groove. Prevent leakage of the packaged goods and prevent foreign matter from entering the inside. (Image source: www.cancentral.com and Visypak Beverage Packaging “Beverage Manufacturing Processes”)
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