The screen-printing process, used today worldwide for printing on garments, was developed in China over 1000 years back and basically, has changed very little. Developments in materials, inks, and chemicals have refined the process but the fundamental approach to passing inks or dyes via a mesh screen to the printable surface remains the same.
It’s possible to get similar quality prints if you are using homemade manual equipment in your garage or operating large automated machines in a manufacturer – a very important factor that will vary greatly though is production times. The following explains the fundamental’spot color’process from somewhere between, ie working together with a small-scale professional set-up using a manual printing carousel:
The first step is to separate your lives the colors in the style using standard software such as for instance Adobe Illustrator or Corel Draw – or to employ the services of any among a number of graphic designers advertising on the internet. For every color, a display must be produced that will be found in turn with all the others to print the image (if printing to dark garments a supplementary screen to make a’flash’undercoat of white ink will be needed to make the colors in the style more vivid). After the colors have been separated they are printed to scale in black to acetate sheets, along with registration marks, using a standard ink-jet printer. The blacked our artwork then must be utilized in the prepared screens.
The conventional screens used have a metal or wooden frame with a tightly woven mesh, usually made from nylon or polyester, stretched across them. Screens with various mesh counts are utilized with respect to the intricacy of detail in the style (generally speaking higher mesh counts are used to reproduce greater detail as less ink can move across the screen). Us Space Force T-Shirts Screens are prepared by coating them with a photo-reactive (light-sensitive) emulsion and then left to dry flat in an area free from UV light. When this solution is dry the screens are ready to really have the artwork’burned’or exposed to them.
A lightbox is now used which can be basically a box containing UV light-emitting tubes, an obvious glass surface above and a material lid. Each acetate is positioned upon the glass area and a prepared screen laid at the top – mesh side down. The material lid is closed and drawn tight within the screen using a vacuum pump – a timer is then set whilst the image is developed to the screen. The emulsion on the screen now reacts and hardens where in fact the UV light hits it and stays soft where in fact the areas of opaque black areas on the acetate block it. When the timer has stopped (anywhere between 1 and 20 minutes with respect to the intensity of UV light) the screen is preparing to be washed off with water using a hose or low powered pressure washer. The water washes away the areas of emulsion that have not developed, creating areas on the mesh for the inks to pass through.
After the developed screens have dried masking tape is applied round the edges to stop ink seeping through areas so it should not. Each screen is then clamped onto an arm of a carousel, mesh side down, and special’plastisol’or water-based ink in each corresponding colour applied on top. To register, or make, the screens a scrap bit of material is positioned within the platens (boards which contain the garments to be printed) and a test print is produced. This is performed by forcing the ink through the clear spaces in the mesh using a hand-held rubber’squeegee ‘, printing the lighter colours first. If printing to dark coloured garments the flash coat of white is printed and then passed under a temperature lamp to touch dry ahead of the colours are applied. The registration marks that are printed onto the scrap material are set up consequently before the finished, registered image is produced. To cure the ink the printed garment is positioned on the conveyor belt of a tunnel dryer and heated to 320 degrees F (160 C). This may prevent the ink from washing away ensure the image will remain for provided that the garment lasts.
If a number of garments are to be printed time is saved by working together with a friend, one T-shirt printing and one loading/unloading. To be certain to getting the best reproduction of your designs and logos always use the very best quality T-shirts and inks that your financial allowance can accommodate.