1. ABSTRACT

 

This is a set of instructions on how to generate silk-screened T-shirts from either an image on your computer or a hardcopy image on paper.
          The image itself must be only black and white, no intermediate shades of gray or color. You can use colored ink with the screen when it’s done. To print more than one color on a shirt, a screen must be made for each color, unless the colors are in separate regions of the T-shirt. If this is case, you can use more than one color of ink on the same screen.
          Please read all of the instructions before starting the process. Some substitutions can be made, and not all things must be done in this order; use your common sense.

 

2. PREPARING THE POSITIVE STENCIL

 

The first thing you need to do is get an image. Any black and white drawing on a computer or a piece of paper will do. If you are using a computer, print the image on the transparency. Otherwise, if it’s a drawing, use a photocopier to copy the image onto a transparency. Make sure that the black areas are fully blacked out, if they aren’t use a permanent marker to fix the errors.

 

3. PREPARING THE SCREEN

 

3.1. Mixing the photo emulsion

Mix 4 parts Emulsion to 1 part Sensitizer. Mixing is best done in an opaque, wide-mouth container with a screw-on cap or lid because the left-over sensitized Emulsion can be stored up to four months when refrigerated away from light.

 

3.2. Coating the screen

Start with a clean screen. Coat the screen by first pouring a bead of the sensitized Emulsion on one end of the bottom side of the screen. Spread it evenly and thinly with the squeegee. Use more Emulsion where necessary. Next, pour a bead of Emulsion on one end of the top side of the screen and spread it evenly with the squeegee. Work to achieve an even continuous coating on both sides of the screen fabric. Always perform the final spreading on the inside of the screen. Try to remove any heavy deposits of Emulsion. Scrape off any excess and return it to the mixing container.

 

3.3. Drying the coated screen

Use the masking tape to tape the 20 pennies into four stacks of five pennies, then tape one stack to each of the four bottom corners of the screen. (Fig. 1)

 

 

Place the screen horizontally inside the cardboard box, and then tape the box shut with the masking tape. Next, place the box somewhere away from light and heat (e.g. basement or closet).

 

4. SETTING UP THE EXPOSURE STATION

 

Before you remove the sensitized screen from the dark drying area, make sure everything you need to print with is on hand. Set up the exposure lamp according to the following table:

 

Screen Size		Bulb Height		Exposure Time
8x10 inches		12 inches		45 minutes
10x14 inches		12 inches		45 minutes
12x18 inches		15 inches		1 hour 14 minutes
16x20 inches		17 inches		1 hour 32 minutes
18x20 inches		17 inches		1 hour 32 minutes

 

A kitchen chair can act as a good base for mounting the lamp. Once the lamp is set at the appropriate height, place the black paper sheet directly under it. (Fig. 2)

 

 

5. EXPOSING THE SCREEN

 

Take the screen, now completely dry, out of the cardboard box and remove the stacks of pennies from the corners. Place the screen centered face-up directly under the 150-Watt light bulb equipped with reflector. Next, place the transparency face up on the screen, and then lay the piece of glass on top of the transparency. Now allow the screen to be exposed for the amount of time recommended above. (Fig. 3)

 

 

6. DEVELOPING THE GRAPHIC

 

Once the exposure time has been reached, place the screen in a bathtub, shower, or large sink. Apply a forceful stream of body-temperature water to both sides of the screen. (Fig. 4) Rub the surface of the screen with the palm of your hand until the unexposed areas become open. Once all unwanted Emulsion has been removed, place the screen in a level horizontal position, and allow it to dry completely.

 

 

7. INKING THE SHIRTS

 

It is always best to make a test run of the screen on a large piece of newsprint before screening any shirts. This helps give you a feel for how much ink is necessary for your design. Place a sheet of newspaper flat inside all of the shirts to be screened, try to keep wrinkles to a minimum.

 

 

Lay the T-shirt flat on a hard even surface. (Fig. 5) Place the screen on top of the shirt, aligning the design with the position you desire it to print in. At the top of the screen, spanning completely from the left side of the screen to the right side spread a generous bead of ink with a spoon. (Fig. 6)

 

Place the palm of one of your hands in the center of the top piece of framing wood that makes up the screen. (Fig. 7) Use this position to hold the screen in place. With the other hand, hold the squeegee at a 45° angle towards you, placing it at the topmost area of the screen. Applying moderate pressure, drag the squeegee towards the bottom of the screen. (Fig. 8) Repeat this until the ink is completely spread over all areas of the design.

 

 

Next, remove your hand from the top of the screen; use it to life the bottom edge of the screen slowly up. (Fig. 9) Allow the inked shirt to completely dry before ironing, if it is necessary to move it before then, lift and carry the shirt from the shoulders’ outer seams. Once the shirt is completely dry, place a piece of newspaper above the inked area and iron (with heat level set to cotton) until the ink is completely set into the fabric (it will have a satin sheen when this occurs).

 

 

8. REMOVING THE PHOTO EMULSION

 

Photo Emulsion should not be left in the screen unless a permanent stencil is desired. It should be removed as soon as the run of shirts is completed. Speedball Photo Emulsion Remover or mixtures of two parts cold water to one part household bleach can be use to remove the Emulsion from the screen. Apply the solution to both surfaces of the screen and store horizontally for five minutes. Spray with hot water to begin removing the Emulsion, then reapply the solution and scrub with a nylon bristle brush. Rinse with a spray of hot water. Once the screen dries, use isopropyl alcohol with a rag to remove any residual Emulsion.

 

9. REFERENCES

 

1. Speedball (1989). Diazo Photo Emulsion Kit: Instruction Booklet. Statesville, NC: Hunt Manufacturing.
2. Speedball (1990). Photo Emulsion Method. Statesville, NC: Hunt Manufacturing.

 

APPENDIX A: List of supplies and where to acquire them

 

Household Items:
20 pennies
Teaspoon
Iron
 
A Screen-Printer (look one up in the yellow pages):
Blank Heavyweight T-shirts - high percentage of cotton is best
 
Art Store (such as Dick Blick or ArtMart):
Diazo Photo Emulsion - Opaque blue liquid in a clear bottle
Diazo Photo Emulsion Sensitizer - Clear yellow liquid in a white bottle
A Large Piece of Black Construction Paper - Larger than your screen
A Squeegee - One with a rubber blade and plastic handle is good
Acrylic Fabric Ink - The kind that is heat set with an iron
A silk-screen - 10in. X 14in. is a good size
 
Framing Store (or any store that cuts glass):
Framing Glass - Have it cut to fit just inside the silk screen’s interior
 
Hardware Store (such as Home Depot or Builder’s Square):
A 150 Watt Light Bulb - Unfrosted glass only
A Clip-on Light with Reflector - Simple portable light with aluminum reflector dish
A Large Cardboard Box - large enough to fit your screen inside
Masking Tape - any other semi-sticky tape will do ok
Duct Tape - any other waterproof tape will do ok
 
Office Supply Store (such as Staples or Office Max):
A Laser printer / photocopier transparency - sized to match design
 
If your design is on a computer
Access to a computer with a laser printer
 
          or
 
If your design is from a black and white image
Access to a photocopier that you can load paper into