Capillary Film
Capillary Film is a pre-sensitized film used for screen printing stencils. It’s normally only applied to a screen when its wet to help the screen fabric before applying emulsion and before exposing the screen. The Capillary film is direct emulsion coated onto clear polyester film. Film recoats until the desire thickness is achieved during the manufacturing. No screen maker can make a stencil as smooth as capillary film. The Capillary films are dense, pinhole-free photopolymer emulsion on a temporary mylar backing.
SHEBRO® THICK FILM SBQ Pure Photopolymer
Shebro® Thick Film (SBQ Pure Photopolymer – Manufactured First in India) is the best choice for the production of thick stencils required for heavy ink deposit in a variety of applications including textile, electronics, and other industrial printing.
Benefits
Clean : You only need your hand for placement of film you can avoid using scoop coater and messy cleanup after.
Consistent : Capillary films are same as emulsion, except it’s coated on sheet of plastic and it has uniform thickness. If you are problem with Coating a screen or multiple hands in project then capillary film makes it very easy and consistence.
FEATURES
- Fast exposure with UV lamps and fluorescent tubes
- Excellent image quality
- Fast screen production
- Red color for easy visual inspection of images
- Fast and easy screen washout
- 100% photopolymer film ensuring long shelf-life
- Available in 100 and 150 micron
HANDLING THE FILM
The film should be handled under low wattage tungsten or yellow fluorescent lighting. The film should be returned to the container after cutting off the required length. Do not kink the film as this could affect adhesion to the mesh. The film should be handled wearing light cotton or lint-free gloves to avoid contact with the emulsion surface. Do not allow the film surface to come in contact with water
MESH PREPARATRION
All new mesh should be abraded vigorously on the printing side with Shebro® Mesh Prep before use. Shebro® Mesh Prep should be used to provide an even water break and to improve adhesion
Film | Thread per cm | Thread per inch |
100mic | 43 to 62 | 110 to 158 |
150mic | 34 to 55 | 86 to 141 |
ADHERING TO MESH
Several methods can be employed to adhere Shebro® Thick Film.
CAPILLARY FILM METHOD
Remove all dust from the emulsion side of the film. Spray the mesh with water and wipe the excess water from the perimeter of the frame to avoid water drops running into the adhered film. Contact the leading edge of the film onto the top of the wet vertical screen and allow the wet screen’s capillary action to adhere the film to the mesh. Remove excess moisture from the inside of the screen with a lightweight window squeegee. Wipe excess water from the perimeter of the frame with an absorbent cloth then proceed to drying.
DIRECT / INDIRECT METHOD
Place the film emulsion side up on a raised surface. Place substrate side of screen onto film. Apply a Shebro® DP TEX to the top edge of the film. Squeegee the emulsion several times until film is completely adhered to mesh.
BACKING WITH EMULSION
Method Mount the Thick Film to the mesh using the Capillary Film Method, allow screen to dry and remove backing. Apply two coats of Shebro® DP TEX to the squeegee side of the screen and proceed to the screen-drying step.
For all above methods, the screen can be further reinforced by applying two coats of emulsion to squeegee side of screen after initial drying.
DRYING THE SCREEN
The screen can be dried with cold or warm air, maximum 43*C. Thorough drying is essential for optimum results. When the support has been peeled off, continue drying for a few minutes to ensure the film is completely dry. Drying should be in either dark or yellow light conditions.
EXPOSURE
It is always recommended to perform a stepped exposure test to determine optimum exposure. As a guideline, refer to times listed in exposure time chart. The preferred test method is with a blue backing emulsion coated onto squeegee side of screen. Optimum exposure is indicated as the shortest time that fully cures through the red film and leaves a hardened layer of blue emulsion on the squeegee side of screen after developing.
Light Source | Shebro® Thick 100 | Shebro® Thick 150 |
1000 Watts/1KW | 100 Seconds | 150 Seconds |
6 Fluorescent Tube light | 12 Mins | 14 Mins |
WASHOUT / DEVELOPMENT
Wet both sides of screen with a strong, finely divided spray of water and continue washing out from print side until all image areas are fully open. Rinse both sides of screen and dry thoroughly before use. A properly exposed and developed screen should not exhibit scrumming or feel slimy on the squeegee side. The use of warm water will decrease washout time.
RECLAIMING
After printing, scrape excess ink from screen and then clean stencil with Shebro® Screen Wash 126. Rinse screen, then strip stencil with ready to use Shebro® Decoater Gel. For stubborn stains it is necessary to apply a Shebro® Haze Remover 3.
PACKING
Shebro® Thick Film is available in thicknesses ranging from 100 to 200 microns. Available in sheet sizes – 50cm X 60cm as well as 50cm X 2mtr rolls.
Why Is My Stencil Wrinkling or Shrinking After Using Capillary Film?
If you use capillary films to create your stencils, and you’re running into problems after you’ve washed out the stencil, it’s possible you’re underexposing your screen or the screen has not been degreased before you applied the film. It could also be from poor mesh prep, or a long duration in water, either before applying the film or during cleanup.
Why Do I Need to Use a Degreaser on Capillary Film?
There are plently of special degreasers or mesh pretreatments that were created for capillary films, and it’s because of the ability to raise the surface energy of mesh, and hold an even amount of water on the surface of the film. If you’re using a dry capillary film and applying it to a wet screen, you’ll need to also consider using an abrader when you degrease your screen. This abrader will help rough up your screen, giving your capillary film a better surface for your film to adhere to.
The information and our technical advice – whether verbal, in writing or by way of trials – are given in good faith but without warranty, and are based on our current knowledge and experience. In view of the many factors that may affect processing/printing and application of our product, these data do not relieve processors/printers from carrying out their own investigations and tests; neither do these data imply any guarantee of certain properties, nor the suitability of the product for a specific purpose. Any descriptions, drawings, photographs, data, proportions, weights etc. given herein may change without prior information and do not constitute the agreed contractual quality of the product.
Our advice does not release you from the obligation to check its validity and to test our products as to their suitability for the intended processes and uses. The application, use and processing of our products and the products manufactured by you on the basis of our technical advice are beyond our control and, therefore, entirely your own responsibility.
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