How Dye Sublimation Printing Works

Screen Printing

One upon a time, the only reasonable way to added a design to a t shirt was screen printing.  Screen printing is what it sounds like, a process of applying a design to fabric using a screen.  Part of the holes of the screen are filled or blocked, and the printing ink goes through those that are open.  By this process, you can only print one color at a time.  Each different color on a design requires a separate screen.  The cost of making these screens is high enough that it only pays to buy printed garments in batches of at least six per color printed.  One color – 6.  Two colors – 12.  Etc.

Direct to Garment Printing

A newer process is direct-to-garment printing.  Once again, this process is what it sounds like.  A garment is placed in a printer, and ink is applied directly from an ink-jet type print head.  We’ll talk about direct to garment printing another time, but it has the limitation that it works best to apply designs to flat pieces of cotton, and requires a costly printer.  Designs of many colors can be printed.  Single garments can be economically printed.

Dye Sublimation Printing

Enter dye-sublimation printing, or transfer printing.  This  technique can be used to apply designs to polyester fabric, and to a wide range of substrates which have been treated with a dye-absorbing polymer.  The key to dye-sublimation printing is a special paper treated with a surface on which an ink can be printed, but which doesn’t absorb ink.  Regular paper is porous, and absorbs inks.  The surface of transfer paper is easy to print on, but doesn’t absorb ink.  Instead, the ink dries on the surface.  Later, the ink can be transferred by heat and pressure (or heat and vacuum) to a polymer surface, such as polyester fabric, that absorbs the ink.

Like direct to garment printing, dye sublimation printing can be used to print multicolor designs economically on as little as one garment.  It can also be used to transfer designs to hats, coffee cups, ceramic tile, etc.  Since the ink dissolves deeply into the polymer, the design is wash-proof, and durable.  All that is required is a printed paper, a polyester fabric or polymer-treated surface, and a gizmo to press the paper against the surface and heat it for ten seconds or so.

See the sublimationprocess

How Perforated Window Vinyl Works

Perforated window vinyl, or “see-through” vinyl is used to make signs that are solid, bright, and opaque when viewed from the outside, but are transparent from the inside.  When I hear about something like this, I have to know how it works to believe it.  So–how does it work?

Perforated vinyl is exactly what the name says, a sheet of vinyl material with a pattern of tiny holes cut through it. There are so many of these holes that a significant amount of the material is removed. The amount of vinyl removed usually ranges from 30 to 50%.  For example, 60/40 vinyl, is 60% vinyl and 40% holes.

Light-colored perforated vinyl signs are opaque when seen from outside a window because our eyes naturally focus on a bright, well-lit surface rather than on the holes and the relative darkness of whatever is behind the surface.  The inner side of perforated vinyl, however, is dark colored.  Here the eye naturally focuses through the dark vinyl to the light and motion outside the window.  Because of this, people inside a store, home or automobile see through the back of the sign to the world outside.

Designing for Perforated Signs

A good understanding of how perforated vinyl works will help you design better one-way vinyl signs.  Because the printed surface of the perforated vinyl must be brighter than the space behind the sign, it is best to avoid large areas of black, blue, purple or dark brown in the design. Lettering and small areas of a design can be dark, but use light or bright colors–whites,  pastels, red, yellow, orange, light blues and greens– for the large areas of your design.

As you design, remember also that a large fraction of the sign surface is missing. Avoid intricate detail and small fonts. Design instead with broad brush-strokes and fonts of 30-point or larger.

Like filmy curtains, perforated vinyl signs are opaque when seen from the outside during daylight, but transparent from the inside.  Like filmy curtains, however, these sign becomes transparent at night when viewed from the outside into a lighted space.  When you plan to use the perforated vinyl inside, pay attention to the lighting on both sides of the sign.

One-way vinyl signs offer a lot of intriguing advantages.  Next time you’re thinking about a sign for your car, store or home, make it big, make it bright, and perforate it.

Owen Decker