Adhesion silk screen coating

The application and adhesion of silk screen coatings is very similar to that of the silk screen ink transfer (printing) process. However, precautions must be taken when applying protective floodcoats, the most common spot and full coverage silk-screen coating process. 

Fiber dmms can be produced to meet a wide variety of requirements. They can be constmcted with adhesives for water resistance, their interiors can be coated, their walls and ends can incorporate metal foil or asphalt-impregnated pHes, and their exteriors can be decorated by painting, varnishing, and silk screening for both ornamental and functional purposes. 

The coating apparafus consisfs of a silk screen mesh fixed to a frame with sufficient tension to squeeze the ink through the screen and onto the blank substrate (e.g., polyimide). The substrate is fixed on an XY fable wifh adhesion fape, and fhe silken screen mesh is masked, wifh an open window in the center for screen printing. The silicon rubber squeeze is a fixed support and can be moved in both X and Y directions. A hot-air or IR ramp is used to dry the coating for solvenf removal. 

Silk screen application is often used when the adhesive has to be applied to specific controlled areas. The liquid adhesive is forced through pores in a cloth or screen. It is possible to coat only selected areas by masking parts of the screen so that adhesive does not pass through in the unwanted areas. Adhesives generally must be specifically formulated for silk screen processing. Very low-viscosity adhesives, with flow characteristics similar to those of coatings, are best for silk screening operations. 

Chem. Descrip. Acrylic oligomer diluted 43% with monomer blend Uses Acrylic in silk-screen inks and plastic coatings, laminating adhesives, additive for improved intercoat adhesion Properties Gardner 1 color vise. 8500 cps (60 C)... 

Uses Intercoat adhesion promoter in silk-screen inks and plastic coatings... 

Uses Urethane-actylic in silk-screen inks tor plastics, laminating adhesives, clear coating for paper, plastics, and wood Features Good exterior durability, flexibility, toughness and adhesion,... 

Chem. Descrip. N-Vinyl-2-caprolactam, stabilized with 10 ppm N,N -di-s-butyl p-phenylenediamine CAS 2235-00-9 EINECS/ELINCS 218-787-6 Uses Reactive diluent for radical initiated UV radiation-cured inks (esp. silk screening), vinyl flooring, wood coatings, release coatings reactive diluent in polymerizations (generates polymers with more hydrophobic char, as well as adhesiveness, strength, and complexing capability) Properties Pale yel. cryst. solid vise. 3.5 cps (40 C) vapor pressure < 0.1 mm Hg (20 C) m.p. 35 C b.p. 117 C (10 mm) flash pt. 110 C V-Cap /RC [ISP]... 

This is a clever modification of flat silk screen printing. The paste adhesive is fed in the center of a rotary perforated drum, it is pumped through a hollow doctor blade into the rotating screen stencil and then through the holes in the drum and applied onto a web or fabric (Fig. 64). The web or fabric is running over a counter roller coated with rubber. 

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