Ecologia

Screen printing

Screen printing is a printing technique that uses a woven mesh to support an ink-blocking stencil.

History

Screen printing first appeared in a recognizable form in Chinaduring the Song Dynasty (960–1279 AD). Japan and other Asian

Impression technique

A screen is made of a piece of porous, finely woven fabric called mes The screen is placed over a material such aspaper or cloth. Ink is placed on top of the screen, and a fill bar (also known as floodbar) is used to fill the mesh openings with ink. The operator begins with the fill bar at the rear of the screenand behind a reservoir of ink. The operator lifts the screen to avoid contact with the substrate and then a small amount of downward force pulls the fill bar to the front of the screen. Thiseffectively fills the mesh openings with ink and moves the ink tank in the front of the screen. The operator then uses a squeegee (rubber blade) to move the mesh down to the substrate and pushes the squeegee atthe rear of the screen. The ink is in the mesh opening is pumped or squeezed by capillary action in the substrate in a controlled and prescribed amount, ie the wet ink deposit is proportional to thethickness of the mesh template or y. As the squeegee moves toward the back of the screen the tension of the mesh pulls the mesh above the substrate (called snap-off), leaving the ink on the substratesurface.h stretched over a frame of aluminum or wood. Originally we used human hair, and then woven silk to make a grid, currently most mesh woven man-made materials such as steel, nylon andpolyester. Areas of the screen is blocked with a non-permeable material to form a template, which is a negative image printed, ie, open space is where the ink will appear.

Printed materials

DischargeInks

is used to print colors on dark background fabrics, which work by removing the ink on the garment - this means that leave a much softer texture. They are less graphic in nature than plastisol...