Adhesives

An adhesive is a substance that bonds materials to the surface of a product. Adhesive performance is directly related to the surface the adhesive is applied to as well as the application procedure used to apply the adhesive. Here at VMS we offer several different types of adhesives required for your specific application.

Important Facts About Adhesives:

A. Markings will not adhere to dirty, dusty, oily, waxy, unfinished surfaces.

B. When applied to a wet surface, markings will not adhere until the moisture is dry beneath and will require additional pressure at that time.

C. When applied to a painted surface, the paint must out gas or dry before a marking is applied.

D. Generally, markings should not be applied to surfaces cooler than 50F (10C) or in areas with high humidity.

General Types of Adhesives:

A. Acrylic – Permanent type of adhesive with 2 sub-types

  1. Pressure Sensitive – Low to high tac, good up to 200F (93C)
  2. Pressure Activated – Adjustable positioning, a squeegee secures the bond, good up to 200F (93C)

B. Rubber – Usually used for removable decals, not recommended for use above 160F (70C). These adhesives have high tac and adhere to substrates with low surface energy such as rubber, Teflon, silicone and plastics such as polyethylene and polypropylene.

C. Thermoset/Elastomeric – To apply the decal, solvent or heat (200F {93C} or  greater), is needed to adhere. This process is unique to Thermoset/Elastometric adhesives.

Selection of an Adhesive

Questions to Consider in Selection of Adhesive:

1. Type of Surface?  Will the part be applied to a rough, smooth, porous, riveted, painted or unfinished surface?

2. Surface Composition?  Does the surface the part will be applied to have a high surface energy such as acrylic, pvc, polycarbonate, polyester, and ABS or does it have a low surface energy such as polystyrene, polyethylene, polypropylene, tedlar and teflon?

3. What temperature range? How hot/cold will the surface get?

4. What environment? Will the part be exposed to or used outdoors, indoors, around chemicals, UV light, cleaners or dirt?

Adhesives Used at VMS:

A. Transfer Adhesive – A layer of adhesive on a paper liner laminated to a rigid film (i.e. Polycarbonate, polyester or rigid vinyl). Transfer adhesives are used in conjunction with subsurface printing and/or top surface printing on white material  (i.e. faceplates, nameplates, overlays and caution/warning labels).

B. Permanent Adhesives – (Pressure Sensitive) permanent adhesives tend  to continue to increase in bond strength with time, usually reaching ultimate  adhesion in 72 hours after application.

C. Removable Adhesives  (Pressure Sensitive) removable adhesives reach their ultimate  adhesion in one to 24 hours after application. The bond strength remains low up to 2 years depending on the product. After this period the adhesives will stiffen up and become permanent. Although termed”removable” from most smooth surfaces, these adhesives may not be completely removable from some matte or textured surfaces. Testing for removability from painted surfaces is strongly recommended. Most suppliers carry removable adhesives on vinyl.

D. Repositionable Adhesives – (Pressure Activated) Repositionable adhesives have low initial tack, but high ultimate adhesion. They can be lifted and reapplied to the substrate during installation without stretching.

During application, a squeegee is used to activate the adhesive. After 24 to 72 hours, adhesion builds up so that the film will be damaged if removal is attempted. This type of adhesive is excellent for fleet markings and in other applications when position is critical.