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PHOTOCURE SR
PVA-SBQ PATENTED PURE PHOTOPOLYMER DIRECT EMULSION DESIGNED FOR COMMERCIAL AND TEXTILE PRINTING
PHOTOCURE SR is a red colored PVA-SBQ presensitized pure photopolymer direct emulsion for UV, commercial graphics and textile (plastisol) inks:
· Exhibiting superior resolution and definition with wide exposure latitude for one color to 4 color process printing.
· Excellent solvent resistance and easy reclaiming.
Extremely durable and resistant to pinholing and breakdown.
Emulsion is presensitized. No diazo required.
· Faster exposure time over conventional diazo type emulsions.
High solids content (~37%) for Quick stencil buildup.
MESH PREPARATION
It is extremely important to clean and degrease the screen mesh prior to each application of Photocure SR. Oils and grease from transportation or storage, residual contamination from inks and cleaning chemicals and general shop dirt can greatly interfere with consistent, smooth coating and increase the chances of stencil breakdown later on.
Ink stains on the mesh can be removed with Murakami's 701 Haze/Ghost Remover. This non-caustic, water soluble liquid is specially formulated for use with all types of inks. Murakami's 801 Degreaser helps eliminate the problems caused by screen mesh contaminants on all types of fabric. It safely controls water hardness and cleans unwanted residue such as oils, grease, dirt and dust
The screen should be rinsed well with water and allowed to dry completely before proceeding with coating.
COATING
The use of a sharp edged coater is preferred, unless the coating is required to be thick, such as on a 110 mesh or under.
DRYING
Dry the coated screen in a clean, light safe area in a horizontal position print side down. Thorough drying of the coated screen is very important. The following conditions will help facilitate and insure complete drying: 86 to 104 degrees F (30 to 35 degrees C) 30% to 40% Relative Humidity Air ventilation i.e. fan essential
An enclosed screen drying cabinet with heated airflow is very helpful in obtaining and sustaining these conditions, as well as keeping your screens free of contamination.

EXPOSURE
The following exposure table should be regarded as guideline only. The use of the Murakami CSC Exposure Scale is recommended to determine the proper exposure time.
NOTE: If you are currently using a diazo type emulsion, your exposure time will be approximately 1/4 of your current exposures. If you are using a diazo/photopolymer (dual cure) type, your exposure will be approximately 1/2 of your current exposure.
EXPOSURE TABLE
All exposure times listed below are established using a 5000W metal halide lamp at 40", 15.5 mW/cm: output below the vacuum glass, and the emulsion thickness being 5 microns. Nanometers of spectral Deak output: 350-400 nm.
| MESH |
TIME |
HARDNESS (CSC Scale) |
| 250 Yellow |
70 seconds |
3 |
| 300 Yellow |
50 seconds |
3 |
| 350 Yellow |
30 seconds |
3 |
| 420 Yellow |
25 seconds |
3 |
Note: It is very important that your exposure is performed with a light source that was specifically developed for screen printing. Exposure time can vary depending on the nanometer output of the light and distance from the vacuum frame.
Note: Because there is no diazo sensitizer, you will see no color change in the image area when the positive is removed
WASHOUT
The image should be washed out using a cold water spray. Wet the stencil completely on both sides. Let it stand for 30 seconds. Wash the image area from the print side until it is clear of unexposed emulsion. Turn the screen around and rinse the squeegee side to remove any residual unexposed emulsion. Blot the screen and frame with a chamois to remove any excess water. Dry the screen in a horizontal position.
RECLAIMING
Scrape all excess ink from the screen. Remove ink residue with a suitable solvent. Flush the screen with water. Apply Murakami 601 Emulsion Remover, Murakami Super Strip-P or diluted Murakami 605 Concentrated Stencil Remover to both sides of the stencil and allow to sit for about 1 minute. (Do not allow the stencil remover to dry on the screen!). We recommend the use of a high pressure washer to remove all stencil residue from the mesh.
STORAGE AND HANDLING
Photocure SR is a very stable product and can be stored in temperatures from 35 to 104 degrees. Photocure SR should not be allowed to freeze. This emulsion has an extended shelf life of 3+ years.
COATED SCREENS
Coated screens have a shelf life of up to one year when kept under the following conditions (in a light safe area):
59 to 77 degrees F (15 to 25 degrees C)
40% to 50% Relative Humidity
We also recommend that an exposed coated screen that has been stored under the above conditions over 2 hours be placed in a drying cabinet for a few minutes prior to exposure.
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