The foamer made of expandable microspheres is a new type of special additive which belongs to polymer particles. Microsphere foaming is a kind of core-shell structure with the core in it a spherical plastic particle composed of alkane gas and the shell outside of thermoplastic polymer which can release hydrocarbon.
Under the indoor temperature, the polymer shell is hard and generally 10-45 microns in diameter. When heated, the shell softens and at the same time the hydrocarbons increase the internal pressure which make the microspheres expand like a ball with the diameter high to 20-200mm. The volume of the microspheres can rapidly expand to tens of times itself thus achieving the goal of foaming. Once the microspheres are cooled, the polymer shell is still hard in the expansion state. So the volume is maintained in the heating state, so the density of the microspheres is reduced while the outside hell has good elasticity to withstand greater pressure so the foaming agent made of expandable microspheres won't break after heating expansion.
The foaming wallpaper take the paper of 100 g/m² as the base materials, coated with the foamer of 300~400 g/m² mixed with expandable microspheres, finally foamed after the printing. This kind of wallpaper is thicker and softer than those ordinary wallpapesr.
Among them, the surface of high foaming wallpaper is showing like elastic and concave-convex; it is a kind of wallpaper with the decorative function and sound-absorbing which is often used for ceiling decoration of opera house and conference room. Low foaming printing wallpaper will print patterns on its surface which mixed with some particular amount foamer in it. By using ink containing anti foaming materials in it to make the surface forms concave- convex patterns with different colors which also known as chemical relief. The pattern on the wallpaper is vivid and with a strong sense of three-dimensional and decorative. And the low foamering wallpaper with a certain elastic will print the patterns on the foaming side which show the effects of relief, wood grain or tiles.
