Why are some hot melt pressure sensitive adhesives more transparent than others? Does color and transparency mean quality? Why do most customers prefer light-colored and transparent hot-melt pressure-sensitive adhesives?

1. Color and transparency of hot melt pressure sensitive adhesive

In the universe where we are, when electrons in any substance are excited by specific energy, they will emit light of different wavelengths, thus showing different colors, which can be observed through human eyes or instruments.

Produce darker colors: When the components of the hot melt pressure sensitive adhesive contain higher polar functional groups and / or double bonds or triple bonds, darker colors are easily produced. Therefore, when the hot-melt pressure-sensitive adhesive formulation contains non-hydrogenated hydrocarbon resin and natural rosin and terpene derivatives and other highly polar raw materials, it will usually be darker than the hydrogenated composition distributor.

Another method to produce a specific color is to add a color filler—organic dye or inorganic pigment to the hot melt pressure sensitive adhesive. Titanium dioxide (TiO2), zinc oxide (ZnO) and carbon black are the most commonly used pigments for producing white and black hot melt pressure sensitive adhesives.

The compatibility between the raw materials in the formula is very good: the compatibility between the raw materials used in the hot-melt pressure-sensitive adhesive formula is very good, that is, they have similar solubility parameters, regardless of the depth of their color, usually the product Will be more transparent.

2. Color and transparency are not a limitation

In many applications, color and transparency may not be a consideration.

Bond Materials will produce hot-melt pressure-sensitive adhesives with better transparency or special colors according to market demand.

How to judge the quality of hot melt adhesive?

1. Viscosity

2. Softening point

3. Molten Gardner Color

4. Heat-Stability

5. Loop tack

6. Peel Strength (180 ℃ or 90℃)

7. Holding power

8. Aging-resistance

9. Cold-resistance

The above is determined by professional instruments.

In addition, in daily work, we can also use simple inspection methods of visual inspection and manual inspection to judge, but this inspection method is extremely inaccurate. And it can only be used by those who have a deep understanding of hot melt adhesives. The method is: visually inspect the hot melt adhesive for impurities, and manually test the toughness and stickiness of the hot melt adhesive. This method is only for simple judgment and must be used with caution.

Bond Materials (Guangzhou) Co., Ltd. attaches great importance to the research and development of hot melt pressure sensitive adhesives. Our company has been constantly innovating according to the needs of the international and domestic markets. Our company has strong product development strength and advanced experimental testing conditions. The products use high-quality raw materials to Performance and quality win, providing customers with tailor-made technical solutions.