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The raw material hot melt adhesive for diapers!

Time : 2020-07-13 Hits : 10

Hot melt adhesives are widely used in sanitary products and play an important role in the overall structure and function of sanitary products. Only by closely combining hot melt adhesives, substrates and production equipment and processes can qualified products be produced.

1. What is hot melt adhesive

Hot melt adhesive is a thermoplastic adhesive. When heated to a certain temperature, it melts into a viscous liquid. After being pressed and cooled to room temperature, the adhesive is completed within a few seconds to form a bond. The typical melting temperature is 65℃~180℃. Because it does not contain any solvent as a 100% solid, it can meet the most stringent air pollution prevention regulations, and there is almost no risk of fire or explosion. Hot melt adhesives still have the following advantages for users:

1) Fast curing speed,

2) Water resistance and excellent storage stability;

3) Because 100% solids are fully available, there is less waste, which can reduce transportation and storage costs;

4) Wide range of substrates, which can be automated.

2. Features and applications

Hot melt adhesives are very versatile. The packaging industry accounts for more than 50% of the hot-melt adhesive application market. These packaging materials include pleated cardboard boxes, corrugated cartons, laminated cans, tape, and other laminated film materials. Non-woven textiles include sanitary napkins and paper diapers. Knitted products include garments and tape. Office supplies include tape, official documents, and self-adhesive labels. The combination of parts includes book packaging, furniture, shoes, etc.

3. Precautions for the use of hot melt adhesive

1.) Viscosity

The use of hot melt adhesive must rely on heaters. The coating machines and methods of different manufacturers have different viscosity.

2.)Curing time and opening time

Hot melt adhesives use heat as the medium, and the colloid is completed after cooling, so the operation time must be controlled during use.

Setting time (setting time): refers to the shortest time that can be formed after coating;

Open time (open time): refers to the longest time allowed after coating to pressing;

4. The source of hot melt adhesive odor

The smell of hot-melt adhesive comes from the hot-melt adhesive itself, which is the essential characteristic of hot-melt adhesive and is affected by raw materials, production process, and circulation. Hot-melt collagen materials include main resins, tackifying resins, thinners or softening oils, and additives. The inherent odor of the raw materials is an important source of hot-melt adhesive odors. For example, most EVA has a slight odor of acetic acid, and synthetic rubber also has The taste of its own is just light and light. The rosin tackifying resin in the tackifying resin has the smell of turpentine, while the C9 and C5 resins have different tastes. Even all the hydrogenated resins have their own taste. Others The raw materials also have a lot of smell, but the density is different, and the strength is different. In the production process, hot-melt adhesives may also have a new source of odor, and the purpose of reducing odor can be achieved through the control of the production process.