PMMA IRK304 Resin and EVA (Ethylene Vinyl Acetate) Tape causes a Stain Mark

[P_Nathan]

Gooday all, we are a plastic injection molding facility involved in telecommunication and optical parts for lens category. We use clear virgin resin. No compound or regrind.

One of our main resin used for molding is PMMA IRK304. When we apply protective tape with EVA (Ethylene vinyl acetate) it causes a stain mark appearance. Anyone with similar experience and care to share how to go about it.

Thank you in advance

 

[Mikishots]

Acrylic resins are espeically sensitive to organic solvents, which causes a breakdown of the resin, usually in the form of clouding or hazing. A common culprit is trichloromethane, present in some tapes. You can ask 3M is they have tapes that do not contain organics in the adhesive formulation.

 

[MIREGMGR]

Right. The culprit likely is the tape adhesive, not the tape body material (EVA).

Generally, pressure sensitive adhesives used on tapes fall into three chemical groups: acrylics, modified rubbers, and silicones. No adhesive of that character is likely to have just a single chemical constituent. Instead it will be a mixture of multiple ingredients. One of the ingredients is your culprit.

As suggested, you need to work with a chemically more sophisticated tape maker, who can provide you with tape coated with better-understood-and-controlled adhesive.

 

[P_Nathan]

Thank you all for the kind inputs. Appreciate it very much