PRINTING
DOUBLE IMPRESSIONS
LIGHT IMPRESSIONS
IMAGE LIGHT ON ONE SIDE, DARK ON OTHER SIDE
BLEED IN PRINT OR HAZY IMAGE
INK DRIES IN SCREEN
May be due to
May be due to May be due to May be due to
May be due to
Moving screen while printing. Secure screen or have someone hold screen while you print!
Insufficient pressure. Press harder! Hold squeegee on more of an angle!
Unequal pressure on squeegee. Press harder on the light side!
Too much pressure on flood stroke or Too much pressure when printing. Reduce pressure!
1. Too much time between prints. Hurry up!
2. Fine lines in artwork. Add retarder to ink!
3. Incorrect mesh. Change mesh! Print faster!
SCREEN MAKING
IMAGE HARD TO WASH OUT
WHITE SPOTS APPEAR WHEN COATING SCREEN
PHOTO EMULSION WASH AWAY
PHOTO EMULSION PEELING EXCESS PINHOLES
May be due to May be due to May be due to
May be due to
May be due to
1. Overexposure during exposing. Change
Time!
2. Artwork not opaque enough. Darken It!
Oil from skin left on screen. Remove photo emulsion, wash the screen thoroughly and start again!
1. Too little sensitizer. Measure Again!
2. Short exposure time. Change time!
3. Improper distance. Change Distance!
4. Water too warm or pressure too strong.
Use cooler water or change pressure!
Emulsion too thickly applied. Apply less!
Emulsion too sparsely applied. Apply more!
When water-based ink dries in screen – use spray bottle with water and spray directly on the screen. Just a small amount will open it up. Certain inks will not wash out if they dry in the screen, so be careful not to leave the screen inked without printing, or the screen may be ruined. CrownTM Retarder works well to slow down drying time and keep screen open longer while printing.
Spray inside of screen only. If the outside gets smeared you must wash the entire outside or print until the smear disappears.
Oil based inks are more flexible in terms of drying time. Use ink thinner or screen wash on a paper towel and apply directly to inside of the screen where the ink has dried. Do not rub the outside of the screen. If the outside is smeared you must clean the entire outside or keep printing until the smear disappears.
Always test print before production runs.
If you have problems that you cannot solve and your local dealer cannot help you, do not hesitate to call our factory.
POSTSCRIPT: ABOUT FABRICS
Choose it or lose it!
The key to good screen making is the proper choice of screen fabric or mesh. If you choose the wrong fabric, you may lose your image. Choose screen fabrics according to:
The delicacy of lines desired in the artwork. Fine lines and broad lines require different fabrics.
The type of printing ink used. Since inks differ in viscosity, check the ink can label for suggested mesh size.
The substrate or object being printed.
Screen Fabrics consist of woven threads. These threads act as strainers for the ink. Tighter weaves allow les ink to pass through the mesh and on to the substrate. More open weaves allow more ink to pass through the mesh and on to the substrate.
Fabric thickness, however, also affects ink deposit. The thickness of the fabric varies according to:
Mesh count: The number of threads per inch. Thread diameter.
There are two categories of fabric construction or thickness: Multifilament and
Monofilament.
Multifilament Weaves
Multifilament weaves are made up of multiple stranded filaments twisted to form a single thread (See Diagram). The surface is rough, less uniform and the fabric is thicker. Photo emulsion adheres very nicely as do hand cut stencils. Thus multifilaments are suited for heavy ink deposits, offer excellent adherence for both knife cut stencils and photo process stencils. Also, multifilaments are usually readily available.
Most commonly used multifilaments are made of polyester. The polyester fabric offers easy removal of the photo stencil. Although silk is also a multifilament, it is not as commonly used
since the photo emulsion cannot be removed without destroying the silk fabric. The chemicals used to remove the photo stencil will disintegrate silk, but polyester is not attacked by such chemicals making it more suitable for photo stencils.
The wide thread thickness of multifilament fabrics create a lower open area in finer meshes which make it difficult to print fine detail. However, multifilaments work very well on textiles where a heavier deposit of ink is needed.
Multifilaments range from 6xx to 25xx. The higher the number, the finer the mesh.
Monofilament Weaves
Monofilament weaves are made up of single-strand threads. The surface is smoother because the single strands can be woven closer than multifilament weaves. Monofilaments are much more uniform than multifilaments. For this reason, hand cut stencils do not adhere well to monofilament fabrics. Photo stencils, however, work well with monofilaments. Because the threads can be made with a thin diameter, monofilament fabrics can be woven in very fine meshes and still retain adequate open area for easy ink passage.
Monofilaments also have very good abrasion resistance and are highly stable. This is needed for fine line quality printing. However, considerably less ink will be deposited. When printing halftones this factor is very important. In selecting screen fabrics for halftone printing, multiply the line dot by three to obtain the minimum fabric mesh to be used. Conversely, to determine the minimum dot size that can be printed with a specific fabric mesh, divide the mesh size by three. However, experimentation with this formula should be done when working with higher line dot sizes.
Monofilament weaves can range from 16 to 470 mesh count. Usually, meshes over 355 are used with ultra violet ink. Because these inks do not dry there is no need to worry about clogging up the stencil.
Note: Colored fabrics are recommended when using monofilaments because longer exposure times will still yield high quality stencils. Since light tends to travel quicker along white fabrics, it may creep behind your artwork and affect the photo emulsion. If the artwork lines are thin or if exposure time is long, the photo emulsion may become overexposed.
Polyester: Excellent all-purpose fabric – for multifilament and monofilament weaves.
Nylon: High stretch factor – for printing irregularly shaped substrates.
Wire Mesh: Extremely stable fabric – low stretch factor – heavy deposit of ink –
print circuits, ceramics, and garments.
Silk: Oldest known fabric used in screen printing – rarely used due to lack of availability, expense, and vulnerability to chemicals.
DOUBLE IMPRESSIONS
LIGHT IMPRESSIONS
IMAGE LIGHT ON ONE SIDE, DARK ON OTHER SIDE
BLEED IN PRINT OR HAZY IMAGE
INK DRIES IN SCREEN
May be due to
May be due to May be due to May be due to
May be due to
Moving screen while printing. Secure screen or have someone hold screen while you print!
Insufficient pressure. Press harder! Hold squeegee on more of an angle!
Unequal pressure on squeegee. Press harder on the light side!
Too much pressure on flood stroke or Too much pressure when printing. Reduce pressure!
1. Too much time between prints. Hurry up!
2. Fine lines in artwork. Add retarder to ink!
3. Incorrect mesh. Change mesh! Print faster!
SCREEN MAKING
IMAGE HARD TO WASH OUT
WHITE SPOTS APPEAR WHEN COATING SCREEN
PHOTO EMULSION WASH AWAY
PHOTO EMULSION PEELING EXCESS PINHOLES
May be due to May be due to May be due to
May be due to
May be due to
1. Overexposure during exposing. Change
Time!
2. Artwork not opaque enough. Darken It!
Oil from skin left on screen. Remove photo emulsion, wash the screen thoroughly and start again!
1. Too little sensitizer. Measure Again!
2. Short exposure time. Change time!
3. Improper distance. Change Distance!
4. Water too warm or pressure too strong.
Use cooler water or change pressure!
Emulsion too thickly applied. Apply less!
Emulsion too sparsely applied. Apply more!
When water-based ink dries in screen – use spray bottle with water and spray directly on the screen. Just a small amount will open it up. Certain inks will not wash out if they dry in the screen, so be careful not to leave the screen inked without printing, or the screen may be ruined. CrownTM Retarder works well to slow down drying time and keep screen open longer while printing.
Spray inside of screen only. If the outside gets smeared you must wash the entire outside or print until the smear disappears.
Oil based inks are more flexible in terms of drying time. Use ink thinner or screen wash on a paper towel and apply directly to inside of the screen where the ink has dried. Do not rub the outside of the screen. If the outside is smeared you must clean the entire outside or keep printing until the smear disappears.
Always test print before production runs.
If you have problems that you cannot solve and your local dealer cannot help you, do not hesitate to call our factory.
POSTSCRIPT: ABOUT FABRICS
Choose it or lose it!
The key to good screen making is the proper choice of screen fabric or mesh. If you choose the wrong fabric, you may lose your image. Choose screen fabrics according to:
The delicacy of lines desired in the artwork. Fine lines and broad lines require different fabrics.
The type of printing ink used. Since inks differ in viscosity, check the ink can label for suggested mesh size.
The substrate or object being printed.
Screen Fabrics consist of woven threads. These threads act as strainers for the ink. Tighter weaves allow les ink to pass through the mesh and on to the substrate. More open weaves allow more ink to pass through the mesh and on to the substrate.
Fabric thickness, however, also affects ink deposit. The thickness of the fabric varies according to:
Mesh count: The number of threads per inch. Thread diameter.
There are two categories of fabric construction or thickness: Multifilament and
Monofilament.
Multifilament Weaves
Multifilament weaves are made up of multiple stranded filaments twisted to form a single thread (See Diagram). The surface is rough, less uniform and the fabric is thicker. Photo emulsion adheres very nicely as do hand cut stencils. Thus multifilaments are suited for heavy ink deposits, offer excellent adherence for both knife cut stencils and photo process stencils. Also, multifilaments are usually readily available.
Most commonly used multifilaments are made of polyester. The polyester fabric offers easy removal of the photo stencil. Although silk is also a multifilament, it is not as commonly used
since the photo emulsion cannot be removed without destroying the silk fabric. The chemicals used to remove the photo stencil will disintegrate silk, but polyester is not attacked by such chemicals making it more suitable for photo stencils.
The wide thread thickness of multifilament fabrics create a lower open area in finer meshes which make it difficult to print fine detail. However, multifilaments work very well on textiles where a heavier deposit of ink is needed.
Multifilaments range from 6xx to 25xx. The higher the number, the finer the mesh.
Monofilament Weaves
Monofilament weaves are made up of single-strand threads. The surface is smoother because the single strands can be woven closer than multifilament weaves. Monofilaments are much more uniform than multifilaments. For this reason, hand cut stencils do not adhere well to monofilament fabrics. Photo stencils, however, work well with monofilaments. Because the threads can be made with a thin diameter, monofilament fabrics can be woven in very fine meshes and still retain adequate open area for easy ink passage.
Monofilaments also have very good abrasion resistance and are highly stable. This is needed for fine line quality printing. However, considerably less ink will be deposited. When printing halftones this factor is very important. In selecting screen fabrics for halftone printing, multiply the line dot by three to obtain the minimum fabric mesh to be used. Conversely, to determine the minimum dot size that can be printed with a specific fabric mesh, divide the mesh size by three. However, experimentation with this formula should be done when working with higher line dot sizes.
Monofilament weaves can range from 16 to 470 mesh count. Usually, meshes over 355 are used with ultra violet ink. Because these inks do not dry there is no need to worry about clogging up the stencil.
Note: Colored fabrics are recommended when using monofilaments because longer exposure times will still yield high quality stencils. Since light tends to travel quicker along white fabrics, it may creep behind your artwork and affect the photo emulsion. If the artwork lines are thin or if exposure time is long, the photo emulsion may become overexposed.
Polyester: Excellent all-purpose fabric – for multifilament and monofilament weaves.
Nylon: High stretch factor – for printing irregularly shaped substrates.
Wire Mesh: Extremely stable fabric – low stretch factor – heavy deposit of ink –
print circuits, ceramics, and garments.
Silk: Oldest known fabric used in screen printing – rarely used due to lack of availability, expense, and vulnerability to chemicals.
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