The screen-printing process, used today worldwide for printing on garments, was initially 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 basic method of passing inks or dyes by way of a mesh screen onto the printable surface remains the same.
It is possible to get similar quality prints if you are using homemade manual equipment in your garage or operating large automated machines in a factory – something that will vary greatly though is production times. The following explains the basic’spot color’process from somewhere between, ie working together with a small-scale professional set-up using a manual printing carousel:
The first faltering step is to separate the colors in the design using standard software such as for instance Adobe Illustrator or Corel Draw – or even to employ the services of any one of several graphic designers advertising on the internet. For each color, a screen needs to be produced which will be found in turn with all the current others to print the image (if printing onto dark garments a supplementary screen to generate a’flash’undercoat of white ink will undoubtedly be needed to really make the colors in the design more vivid). When the colors have been separated they’re printed to scale in black onto acetate sheets, as well as registration marks, utilizing a standard ink-jet printer. The blacked our artwork then needs to be used in the prepared screens.
The standard screens used have a metal or wooden frame with a tightly woven mesh, usually made from nylon or polyester, stretched across them. Screens with different mesh counts are utilized with regards to the intricacy of detail in the design (generally speaking higher mesh counts are used to reproduce greater detail as less ink can go through the screen). Screens are prepared by coating them with a photo-reactive (light-sensitive) emulsion and then left to dry flat in a location clear of UV light. Us Space Force T-Shirts When this solution is dry the screens are ready to truly have the artwork’burned’or exposed onto them.
A lightbox is now used that is basically a box containing UV light-emitting tubes, an obvious glass surface above and a material lid. Each acetate is placed upon the glass area and a prepared screen laid on the top – mesh side down. The material lid is closed and drawn tight over the screen utilizing a vacuum pump – a timer is then set while the image is developed onto the screen. The emulsion on the screen now reacts and hardens where in actuality the UV light hits it and stays soft where in actuality the aspects of opaque black areas on the acetate block it. When the timer has stopped (anywhere between 1 and 20 minutes with regards to the intensity of UV light) the screen is ready to be washed off with water utilizing a hose or low powered pressure washer. The water washes away the aspects of emulsion that have not developed, creating areas on the mesh for the inks to pass through.
Following the developed screens have dried masking tape is applied round the edges to prevent ink seeping through areas so it should not. Each screen is then clamped onto a supply of a carousel, mesh side down, and special’plastisol’or water-based ink in each corresponding colour applied on top. To join up, or line up, the screens a scrap bit of material is placed over the platens (boards which support the garments to be printed) and an examination print is produced. This is performed by forcing the ink through the clear spaces in the mesh utilizing a hand-held rubber’squeegee ‘, printing the lighter colours first. If printing onto 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 which can be printed onto the scrap material are set up subsequently until the finished, registered image is produced. To cure the ink the printed garment is placed on the conveyor belt of a tunnel dryer and heated to 320 degrees F (160 C). This will stop the ink from washing away ensure the image will remain for so long as the garment lasts.
If several garments can be printed time is saved by working together with a friend, one T-shirt printing and one loading/unloading. To be sure of getting the most effective reproduction of one’s designs and logos always use the best quality T-shirts and inks that your financial allowance can accommodate.