Screen Printing Honor - advanced

Arts & Crafts

Requirements

1. Have the Screen Printing Honor.

   Answer: You first need to master the basic technique of a stretched screen, simple exposure, plastisol ink, and monochromatic printing. — Screen printing was industrialized in the USA in the 1910s with Samuel Simon and popularized by Andy Warhol in the 1960s; the professional level requires methodical technical progression.

2. Stretch and fasten a mesh onto a frame to make a screen-printing screen.

   Answer: You stretch the mesh (polyester or nylon) with uniform tension in all directions, fasten it with industrial epoxy glue or pneumatic staples to the wooden or aluminum frame, and let it dry flat for 24h. Correct tension ensures a crisp reproduction. — The typical tension of professional screens is 18-25 N/cm for nylon and 25-35 N/cm for polyester, ensuring elastic recovery after each pass of the squeegee, according to the standards of Saati and Sefar, currently in global use worldwide.

3. Know which fabrics can be used for screen printing and the advantages of each one. What factors influence the choice of the mesh for the screen?

   Answer: You mainly use polyester (the most used, durable, does not absorb water) and nylon (more elastic, less resistant). — Meshes with mesh count 110 (43 threads/cm²) are the most used for printing on T-shirts with plastisol, while 305 (120 threads/cm²) are used for printing on glass with fine inks, according to Saati Group.

4. Understand each of the following printing techniques in Screen Printing:
   • Stencil film method
   • Photographic method
   • Resist method

   Answer: The main engraving/printing techniques in screen printing are: 1) Direct blocking (film cutting or manual blocking): the areas that should not print are manually covered with a liquid blocker; simple and cheap, suitable for large designs without much detail. 2) Photosensitive emulsion (photomechanical/photolith technique): emulsion is applied to the mesh, dried in the dark, and exposed to UV light through a film positive that blocks the light in the areas of the design; it is washed with water and the unexposed emulsion comes out, leaving the design open on the screen — it is the most used one because it reproduces fine details. 3) Film stencil (cut paper/film): the image is cut out of paper or film and fixed under the screen; quick for small runs. 4) Decal/transfer (transferring): printing onto transfer paper and then applying it to the object with heat. In all of them, the ink is forced through the mesh in the open areas with the aid of the squeegee (puller), while the blocked areas prevent it from passing through. — Diazo photoemulsion, the current standard, was developed in the 1970s and revolutionized screen printing by allowing the reproduction of photographic gradations, including the iconic works of Andy Warhol from the modernist American art period, still in global use today.

5. Use two of the following techniques to fulfill requirement 4 of this Honor:
   • Print a design using two or more colors, according to the color chart
   • Print a design in repeat
   • Print a design in three colors, using only two colors of ink

   Answer: You use the principle of overlaying: print the first color (e.g.: yellow), then the second color (e.g.: red), and where the two overlap a third color (orange) appears. — The theory of subtractive colors (CMY) explains that mixing yellow and cyan generates green, cyan and magenta generates blue, etc., used in offset printing since 1907 and adapted for screen printing on T-shirts.

6. Print at least 10 identical T-shirts for your unit, Club, or Church project, using at least 5 different screens, with at least 3 of them being of the same design (overlaid).

   Answer: You prepare an adhesive platen to fix the T-shirt, align the screens with precise registration guides, maintain uniform squeegee pressure with each pass, let it dry between colors, and keep the screens clean to avoid clogs in the final process. — The ABCDE sequence (from yellow to black) is the standard industry protocol to avoid contamination between colors, according to the Sefar and Saati manual for multicolor printing on T-shirts, currently in global use worldwide.

7. Print on a material that is not paper or fabric, such as, for example, glass, metal, or leather.

   Answer: You use two-component epoxy ink for glass/metal and polyurethane ink for leather. Apply an appropriate primer, use a higher mesh count (180-305 threads/cm²) for fine details, and cure according to the instructions (open air 24-72h or oven 150°C for 30 min). — Industrial screen-printing inks for glass contain vinyl resins and silicates that adhere permanently after thermal curing, being used on beer bottles, cosmetic jars, and industrial packaging, currently in global use worldwide.