Peelable coatings

The finished outer surfaces of the assemblies may be coated with a peelable coating compound which can be easily sprayed and air dried. The coat forms a translucent peelable film, suitable for protecting the finished surfaces during assembly, transportation and installation from scratches, oil marks, grease and dirt etc. The film can be neatly stripped after the equipment is finally installed. Approximate spraying data are ... 

Uses Acrylic for clear or pigmented peelable coatings, extremely low VOC coatings, spray booth coatings, temporary product proteclanls, and paint masks... 

Polyvinyl alcohol solutions are also used as adhesion binders for non-woven fabrics, screen-printing, ferrites, ceramics and some building materials. In powder form, it is also an effective binder for finely divided powders, such as pigments. Mixtures of low dp polyvinyl alcohol with ethylene glycol, however, have low adhesion to substrates and are used as peelable coatings for metals and plastics for protection during storage and transport. 

Aluminium overcaps may have a perforated metal, plastic fhp-off or peelable foil cover. Figure 6.21 shows typical combination and conventional seals. Vials have also been introduced for unit dose packs using either an aluminium two-piece tear-off closure with a Saran coated pulpboard liner or a peel-type seal. 

Sachets can be fabricated from a single web with a centre fold, using a three or four sided seal or two webs using a four sided seal. The reels may be fed horizontally or vertically and be sealed by a series of heated platens or rollers (cylinders) or a combination of the two. In certain ways they are an enlarged version of a strip pack. The sachet seal can also be made peelable by a non-seal part on the web which may involve a pattern lacquer rather than a full heat seal coating. Difficult to tear plies, like PET, can also be used provided a cut or V-notch is added to initiate the tear. 

An inhibited polymer coating represents a layer of a polymer-based composite material bonded with the substrate via an adhesive layer. The composite material may contain a plasticizer, corrosion inhibitor and technological additives in its composition (see Chap. 3). The coatings are subdivided into peelable and unpeelable by their behavior and the intensity of their adhesive interactions with the article being protected. 

Uses Used in automotive lacquers, lacquers for plastics and paper, wood finishes, nail polishes, coatings for fabrics and leather, peelable plastic coatings, heat-seal adhesives food pkg. adhesives, coatings, paper/ paperboard, cellophane, film... 

Uses Binder, carrier, compounding agent, dispersant, stabilizer, protective colloid in polymerization textiles paper adhesives cement/plas-ter additive peelable caulks ceramics strippable coatings mold release nonwovens Trade Names Airvol 205... 

Paper can be used as lidding material for semirigid and flexible trays, and for peelable pouches. Adhesive coatings are required to allow sealing. 

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