Glass Screen Printing Process, Inks, Applications and Advantages

What is Glass Screen Printing?

Glass screen printing, also known as glass printing or glass decal application, is a printing technique used to apply designs, patterns, logos, text or images onto glass surfaces. It involves transferring ink through a mesh screen onto the glass substrate. The printed design becomes fused with the glass surface after going through a high temperature kiln firing process. Glass screen printing allows for beautiful, vibrant and durable prints on glass.

How Does Glass Screen Printing Work?

The glass screen printing process involves several steps:

1. The artwork is first created and separated into different color layers if multicolor prints are required.
2. Each color layer is burned onto a separate screen mesh using a photosensitive emulsion.
3. The areas blocked out on the screen become solid when exposed to UV light. The open mesh areas remain open.
4. Screens are then aligned and mounted onto the printing press.
5. Ink is applied to the screen and a squeegee is used to push it through the open areas of the mesh onto the glass below.
6. The ink is cured and bonded to the glass through firing in a high temperature kiln or glass furnace.
7. For multicolor designs, each subsequent color is printed in alignment to the first down to the finished design.

Types of Glass That Can Be Screen Printed

Many types of glass can be screen printed including:

• Soda-lime glass - Common transparent glass used for windows, glassware etc.
• Borosilicate glass - Heat and chemical resistant glass used for cookware and lab equipment.
• Lead crystal glass - High quality leaded glass used for decorative ware.
• Opaque colored glass - Used for stained glass, colored glassware and other decorative items.
• Low iron glass - Extra clear glass used when high visible light transmittance is needed.
• Quartz glass - Extremely heat resistant glass made from silica.

The glass surface needs to be compatible with the screen printing ink used in order to achieve a durable print. Pre-treatment such as flame polishing or acid etching may be required on some glass types.

Advantages of Screen Printing on Glass

There are several benefits that make glass screen printing a popular choice for glass decoration:

• High print quality - Screen printing allows for fine details and crisp edges even on intricate designs.
• Vibrant colors - A wide range of opaque glass colors are available for bright and vivid prints.
• Durability - Prints are fused into the glass so they don't scratch, fade or peel off easily.
• Versatility - Almost any design can be printed including complex multicolor graphics or effects.
• Resists high temperatures - Printed glass maintains its decorations even when subjected to high heat.
• Cost effective - Glass screen printing provides beautiful prints at a competitive cost.

Types of Glass Print Designs

Glass screen printing allows for many decorative design options including:

• Logos and graphics - Vector art, company logos, illustrations and more can be printed.
• Text and messages - Printing custom names, monograms, inspirational quotes or text.
• Patterns and motifs - Repeating prints of geometric shapes, floral designs, lines or custom motifs.
• Silhouette prints - Solid color opaque prints of people, animals, objects or scenes.
• Photos and imitation stain glass - Digitally printed full color photos or faux stained glass window designs.
• Artsy prints - Modern art, custom drawings, abstract designs or artistic graphic prints.

With glass screen printing, if you can dream it, you can print it! Almost any design can be reproduced on glass.

Types of Glassware That Can Be Printed

Some examples of glassware that are commonly screen printed include:

• Drinkware - Beer mugs, cups, shot glasses, wine glasses, cocktail glasses, tumblers.
• Barware - Decanters, flasks, pitchers, shakers, martini glasses.
• Kitchenware - Ovenware, bakeware, food storage containers, measuring cups.
• Tabletop items - Serving platters, bowls, vases, candle holders, coasters.
• Bathroom items - Soap dishes, toothbrush holders, lotion dispensers, mirrors.
• Home decor - Vases, bowls, trays, lamps, tiles, doorknobs, wall art.
• Outdoor items - Garden stones, ornaments, sun catchers, hanging prisms.

The smooth, non-porous surface of glassware makes an ideal printing substrate for screen printing. Decorated glassware also makes for great personalized gifts.

Common Glass Screen Printing Inks

The ink used for glass screen printing needs to bond chemically with the glass surface when fired. Common ink types include:

• Ceramic glass colors - Opaque inorganic pigments mixed with low melting point glass frit.
• Transparent glass stains - Organic dyes mixed with solvents and glass frit.
• Silver glass inks - Silver particles in a carrier base that fire reflective silver.
• Enamel colors - Pigments formulated to bond with glass at high temperatures.
• Precious metals - Gold, platinum and other costly metal flakes for luxury prints.

The ink must be compatible with the type of glass being printed on. Firing temperatures are also based on the ink used.

Firing Process for Glass Screen Printing

Once printed, the glass goes through a firing process to permanently fuse the inks. Firing can be done in:

• Small kilns - For firing glassware, decals and small items.
• Large glass furnaces - For firing large glass panels and sheets.
• Laser engraving machines - For some ink types that don't require high temperature firing.

Firing temperatures vary based on the glass and ink type but typically range from 250°F to 1500°F. The ink chemically reacts with the glass surface during firing to create a durable print.

Applications of Screen Printed Glass

Some popular uses of screen printed glass include:

• Custom glassware - Printed beer mugs, cups, bowls, glasses, barware.
• Award plaques and plates - Add logos and custom messages.
• Architectural and decorative glass - Doors, dividers, lighting, wall art.
• Appliances - Printed oven doors, refrigerator panels, range tops.
• Display cases - Silkscreened cabinets, trophies, display boxes.
• Signage and advertising - Point of purchase displays, glass company signs.
• Automotive glass - Printed windshields, mirrors, dash panels, lights.

Screen printing provides a versatile solution for decorating and customizing glass items of almost any size and shape.

Summary

Glass screen printing allows for stunning custom prints and decorations to be added to all types of glass materials and items. Using specialty inks and high temperature firing, the prints are fused into the glass for a durable, permanent finish. With the ability to print razor sharp details and vibrant graphics, glass screen printing opens up many creative possibilities for glass decoration and personalization.

FAQs

What types of glass can be screen printed?

Many glass types can be printed including soda-lime glass, borosilicate glass, lead crystal, colored opaque glass, low iron glass, and quartz glass. The surface must be compatible with the inks.

Does the print scratch off the glass?

No, the printed ink is fused into the surface during firing. This makes the prints very durable and permanent.

Can you print full color images?

Yes, full color photos and designs can be printed with halftone screening and CMYK color separation techniques.

What temperature does glass need to be fired at?

Firing temperatures typically range from 250°F to 1500°F depending on the glass and ink type used.

Can you print on glass bottles or curved surfaces?

Yes, the screen can be made to conform to curved glass surfaces. Special jigs help hold round bottles for printing.