Screen printing

Basics of screen printing.

3. Screen Screen
PrintingPrinting

4. History - beginningsHistory - beginnings
•Screen-printing first Screen-printing first
appeared in a appeared in a
recognizable form in recognizable form in
China during the Song China during the Song
Dynasty (960–1279 CE). Dynasty (960–1279 CE).
Japan and other Asian Japan and other Asian
countries adopted this countries adopted this
method of printing and method of printing and
advanced the craft using advanced the craft using
it in conjunction with block it in conjunction with block
printing and paints.printing and paints.

5. History – western introductionHistory – western introduction
•Screen-printing was introduced to Western Screen-printing was introduced to Western
Europe from Asia sometime in the late Europe from Asia sometime in the late
1700s, but did not gain large acceptance 1700s, but did not gain large acceptance
or use in Europe until silk mesh was more or use in Europe until silk mesh was more
available for trade from the east and a available for trade from the east and a
profitable outlet for the medium profitable outlet for the medium
discovered.discovered.

6. History – popularity increasesHistory – popularity increases
•Screen-printing was first patented in Screen-printing was first patented in
England by Samuel Simon in 1907. It was England by Samuel Simon in 1907. It was
originally used as a popular method to originally used as a popular method to
print expensive wall paper, printed on print expensive wall paper, printed on
linen, silk, and other fine fabrics. Western linen, silk, and other fine fabrics. Western
screen printers developed business screen printers developed business
policies intended to keep secret their policies intended to keep secret their
workshops' knowledge and techniques.workshops' knowledge and techniques.

7. •Originally a profitable industrial technology, Originally a profitable industrial technology,
screen printing was eventually adopted by artists screen printing was eventually adopted by artists
as an expressive and conveniently repeatable as an expressive and conveniently repeatable
medium for duplication well before the 1900s. It medium for duplication well before the 1900s. It
is currently popular both in fine arts and in is currently popular both in fine arts and in
commercial printing, where it is commonly used commercial printing, where it is commonly used
to print images on T-shirts, hats, CDs, DVDs, to print images on T-shirts, hats, CDs, DVDs,
ceramics, glass, polyethylene, polypropylene, ceramics, glass, polyethylene, polypropylene,
paper, metals, and wood. paper, metals, and wood.

8. The process of forcing ink The process of forcing ink
through a porous fabric through a porous fabric
and the open areas of a and the open areas of a
stencil to produce an stencil to produce an
image.image.

9. Screen Printing ProcessScreen Printing Process

10. 1960’s to present1960’s to present
•Credit is generally given Credit is generally given
to the artist Andy to the artist Andy
Warhol for popularizing Warhol for popularizing
screen printing screen printing
identified as serigraphy, identified as serigraphy,
in the United States. in the United States.
Warhol is particularly Warhol is particularly
identified with his 1962 identified with his 1962
depiction of actress depiction of actress
Marilyn Monroe screen Marilyn Monroe screen
printed in garish colors.printed in garish colors.

11. Two terms commonly used: Two terms commonly used:
Serigraphy (in the field of Serigraphy (in the field of
fine arts) and Screen fine arts) and Screen
Printing used in the graphic Printing used in the graphic
communications industry.communications industry.

12. Applications for Screen Applications for Screen
Printing:Printing:
•PostersPosters
•Plastic bottlesPlastic bottles
•Drinking glassesDrinking glasses
•Soda bottlesSoda bottles
•Mirrors, metal surfacesMirrors, metal surfaces
•WoodWood
•TextilesTextiles
•Printed circuit boardsPrinted circuit boards
•Product displaysProduct displays
•Vinyl bindersVinyl binders

13. Advantages of Screen PrintingAdvantages of Screen Printing
•Images can be printed on a wide variety of Images can be printed on a wide variety of
substrates.substrates.
•The production process is relatively easy.The production process is relatively easy.
•Capital expenditures are low compared to other Capital expenditures are low compared to other
printing processes.printing processes.
•Images can be printed with glitter, flock, and Images can be printed with glitter, flock, and
other decorative finishes.other decorative finishes.
•The ink film is very resilient due to the extreme The ink film is very resilient due to the extreme
thickness of the ink deposit.thickness of the ink deposit.

14. Disadvantages of Screen Disadvantages of Screen
PrintingPrinting
•The process is usually limited to flat, relatively The process is usually limited to flat, relatively
thin substrates, such as paper, metal, or thin substrates, such as paper, metal, or
plastic.plastic.
•Rate of production is slow.Rate of production is slow.
•Ink mileage is poor.Ink mileage is poor.
•Excessive drying times may be necessary.Excessive drying times may be necessary.
•Details and fine line images may be difficult to Details and fine line images may be difficult to
print.print.

15. Basic tools & Equipment for Screen Basic tools & Equipment for Screen
Printing:Printing:
•FrameFrame
•SqueegeeSqueegee
•Vacuum Printing FrameVacuum Printing Frame
•Printing TablePrinting Table
•Screw DriverScrew Driver
•DividerDivider
•HammerHammer
•Sharp KnifeSharp Knife

16. FramesFrames
Materials
◦Wood– less expensive, warps or rots faster
◦Aluminum– more expensive, durable
 Sizes
◦Labeled according to I.D. (inside dimension)
Recommended sizes for printing: at least 6 inches beyond.
Image size at top and bottom: at least 6 inches on each side.
 Types
◦Wooden with groove: made for attaching fabric with a rope.
◦Wooden or aluminum without a groove: fabric attached with glue.
◦Retensionable aluminum: screen can be tightened repeatedly.

17. FabricsFabrics
•Two main functions
•Provide support for stencil.
•Control ink flow.
• Mesh count: how many opening per inch.
•Fine mesh=100 count (ct) up to 500 ct. mesh
•More detail and uses less ink; feels softer to touch.
•Less likely to smear on non-absorbent substrates.
•Coarse mesh=40 to 100 ct. mesh
•Heavy ink deposit (good for light inks on dark shirts.
•Better opacity

18. FabricsFabrics cont…cont…
Two general types
Multifilament: tiny strands twisted together
Includes: polyester and silk
Good for film stencils (like amber film)—sticks to it better
 Monofilament: (mono= one) single strand of thread
Good for liquid emulsion
Includes polyester; stainless steel
Good for fine detail; easier to clean than multifilament

19. FabricsFabrics cont…cont…
Colored Fabrics: used to reduce unwanted glare during
exposure, called “halation’s.” Halation’s cause distortion
around edge of images.

20. Chemicals Used In Screen
Printing
Autosol.
Photocure Texture.
Sp-1300.
Benzene.
Carbon tetra chloride
Detergent powder
Glue(swan Aica)
Cold and clean water

21. Light Sensitive Film For Screen
Printing
Direct film
Indirect film (Pre-sensitized gelatin film & Pre-sensitized synthetic
polymer coated film. Known as five star film)
Indirect film used for indirect stencil making.

22. StencilsStencils (Two Types) (Two Types)
Non-photographic: hand cut (i.e. amber film, or paper)
Photographic: (light sensitive) photo emulsion (liquid)
◦Exposure process: Some type of light is used to harden emulsion.
Why does the image spray out?- The particles in the emulsion that the
positive was not covering, was hardened by the UV light.

◦Overexposure: results in image NOT spraying out completely.
◦Underexposure: results in scuming (an almost invisible film forms
on stencil from the still soft emulsion running across screen as it
dries)

23. Stencil Making
There are two way of stencil making.
Direct process.
Indirect Process

24. Stencil Making of Direct Process
In a darkened room or in a room with
a yellow safe light, pour the emulsion
into a scoop coater

25. Coat the screen, applying 2 thin coats of
emulsion on each side of the screen.

26. If your scoop coater is
smaller than the width of
your screen, coat as
shown in this slide.
Once you have one coat
on this side, turn the
screen upside down to
apply the second coat.
Then apply two thin
coats onto the back side
of the screen, again
flipping the screen
upside down in between
coats.
Wipe off any excess
emulsion that gathers
around the edges.

27. Store the coated screens
in a dark room or light-tight
box until they are dry.
Screens should dry with
the flat side down (the side
you used the squeegee on
should be facing up). They
need to dry perfectly flat. If
the screen is tilted even
the slightest bit, then the
emulsion might dry
unevenly and run off the
screen.

28. If you are coating
more than one
screen, stack them
using small blocks
in between each
one.

29. Once the screens
are dry they may be
put in black plastic
garbage bags until
you are ready to
expose them

30. Expose the silkscreen with the students’ Film
Positives. There are different types of exposing
units. This one is a light table with clear glass
and florescent light bulbs.

31. This process involves direct contact exposure. There must be
no space between the Film Positive and the screen. Build a flat
that is larger than your image, but small enough to fit inside the
screen to ensure direct contact. Cover the flat in padding and
black fabric to protect the screen.

32. Weigh down the flat with something heavy.

33. After your exposure
time is up, rinse the
screen on both sides.
The emulsion that was
not exposed to light
(because it was
blocked by the opaque
black areas of the Film
Positive) will wash
away. Wash the
screen until there are
very few white bubbles
remaining. Store the
screen on a flat
surface to dry or use a
fan.
When dry, screen is
ready to proof.

34. InksInks
Consist of…Consist of…
◦Pigment--- provides the Pigment--- provides the colorcolor
◦Vehicle--- gives it “bulk”Vehicle--- gives it “bulk”
◦Solvent--- makes it flow, then evaporates, leaving the rest of the Solvent--- makes it flow, then evaporates, leaving the rest of the
ink behindink behind
◦Modifiers--- examples: thinners; phoshluorescents; puff agents; Modifiers--- examples: thinners; phoshluorescents; puff agents;
etc.etc.

35. Types of InkTypes of Ink
Conventional– dry by air
Water based
Solvent based
 Non-conventional– cured by “polymerization”
Plastisol– cured with heat (325 degrees); used for absorbent
materials only (textiles); won’t work on paper, except for heat
transfers.
 UV (ultraviolet) inks– cured with UV light; for
non-absorbent substrates such as vinyl, and
coated papers. Quick, clean method.

36. Inks cont…Inks cont…
Process inks vs. spot colors
Process inks- ________, ________, _______,________
combined to produce full color prints. Process inks have less
“opacity.”
Spot color– one or more colors to improve appearance without
expense of process printing (or could be a special color added to
a process print)

37. Squeegees
Three main purposes
Force ink through mesh
“Flood” stroke: purpose
Control ink deposit

38. Squeegees cont…Squeegees cont…
Recommended size: Recommended size: two inches wider than image width two inches wider than image width
(maximum)(maximum)
Storage:Storage: Blade up Blade up
Blades vary in:Blades vary in:
◦Material: vinyl or rubberMaterial: vinyl or rubber
◦Hardness: durometer rating (the higher the rating, the stiffer the Hardness: durometer rating (the higher the rating, the stiffer the
blade)blade)
◦Shape: Shape:

39. Squeegee cont…Squeegee cont…
Clean-up
Water based ink- cleans up with Water!!
Plastisols require __________ (paint thinner) or other specially
made ink cleaning solutions.
Liquid (direct) emulsion– remove by degreasing first to get rid of
ink solvents left behind, then apply reclaimer.

40. Potential for Further Development
The main focus of further development lies principally in the plate
making sector:
•The direct imaging of screens (computer to screen) will become more
and more prevalent, especially in conjunction with rotary screen
printing units for large print runs.
•The already available but still little used filmless stencil production
with ink jet printing technology is of particular interest for large format
applications. At approximately 600dpi, the resolution guarantees
sufficiently good print quality even with color gradations.

41. Computer to
screen for
screen
printing
•Computer to screen printing is the digital
production of image carriers for screen printing
in which the print image data, controlled
directly via the computer, are output onto the
stencil or screen. Most computer to screen
systems work using the ink jet technology, in
which either heated wax or ink is applied to the
screen.
•First the screen must be lined with a closed
layer/ emulsion (stencil material). The print
image is applied to this coating using ink jet ink
(as a film substitute). This is then followed by
the usual exposure to cure the stencil material.
The uncured ink-covered areas of the coating
are then washed off with water. After drying, the
stencil/ screen plate is ready for printing.

42. Different type of screen printing process

43. Modern
screen
printing
proces
s

44. Terms to Know!Terms to Know!
Scum:
Unexpected image which comes from stencil or plate.
Haze:
Generalized faint staining of screen mesh caused photo
stencils, screen filters, printing mixtures and varnishes: cf. ghost.
Fisheye:
Unwanted open area in a photo stencil which prints with
the appearance of the eye of a fish.
Margin:
Perimeter of mesh adjacent to the frame of the screen: this non
printing area is closed during printing, either temporarily or
permanently, to protect the mesh and to be used as a printing mix
reservoir.
Digital positive:
Positive created and output using a computer.

45. Artwork:
A general term for photographs, drawings, and others materials
prepared to illustrate printed matter.
Heat transfer paper:
The substrate used in thermal transfer printing. The design
is first printed on it with inks containing sublimely
dispersed.
Flood stroke:
The squeegee motion that deposits a thick layer of ink on
top of the screen printing screen under light pressure. The
excessive ink prevents the image areas from drying
between printing strokes.
Mesh aperture:
The space between the woven threads of screen printing
fabric, through which the ink passes during printing.

46. Screen opener:
A chemical, usually in aerosol spray from, used to
clear dried-in areas of a screen printing stencil.
Dark reaction:
In an unexposed light-sensitive emulsion or
coating, the sloe chemical change that occurs when
the material is stored in an unlighted area.
Mesh?
Stencil?