Everything About Ceramic Decals
                    General Questions for a General Kind of Guy

 On the Left, 9 burning questions that everyone wants to know the answer to... I guess. These are:

1 – What is a Fired Decal?

2 – What happens when a Ceramic Decal is fired?

3 – What about food safeness?

4 – Do you always have to fire a Ceramic Decal?

5 – What other ways can you use a Ceramic Decal?

6 – Can you make a Ceramic Decal on a computer printer?

7 – What if I want to make a Ceramic Decal?

8 – What if I want to have a Ceramic Decal made for me?

9 – Which company do you recommend for Open Stock Decals?

On the Right, Powers of 10 (or, how quantity affects prices and delivery) and a few terms defined, namely:

    Open Stock Decals                  Glass Decals                       Heat Release Decals
    Custom Decals                        Organic Decals                        Inglaze Decals
    Expedited Decals                    Ceramic Decals

What is a Fired Decal?

A fired decal in made from inorganic components which will not burn away in a firing. They usually consist of powdered ground glass (which promotes melting and fusing)(aka. a “flux”) and metallic oxide pigments and salts (for color) mixed with a liquid, oil like, organic (or plastic) printing media suitable for silk-screen printing. After printing the design, it is covered with a temporary plastic carrier (cover coat). The paper which it is printed on is a porous paper with a water soluble coating on one side. This coating consists usually of dextrin or starch which dissolves when the decal is put in water, thus releasing the decal from the paper so that it may be mounted. Such decals are called “water-slide decals”.

During the firing process the cover coat and media (aka. printing vehicle) burn away while the ground glass melts and encapsulates the oxide, fusing it to the ware that the decal has been applied to.

Prior to firing, the colors are dark or dull or even odd, mere approximations of their post-firing brilliance. Firing in a kiln under extreme heat (up to 1500° Fahrenheit) causes the decals to undergo a dramatic transformation, as the oxides and salts fuse and reveal their rich palette of colors. This brilliant image becomes an integral, permanent part of the ceramic material which will not fade with time nor by exposure to bright sunlight, and can only be removed by mechanical abrasion or by strongly acidic chemicals. Basically, it lasts forever.


What happens when a Ceramic Decal is fired?

Firing Cycle Overview

72-212° F (22-100° C)

Decal becomes soft (thermoplastic), melting and conforming to the micro structure of the glaze.

212° F (100° C)

Any water under the decal turns to steam (1 gram of liquid water will expand to 1.25 Liters of steam).This is the major cause of pinholes or blowouts and why we let decals dry 24 hours before firing them.

212-480° F (100-250° C)

Not much happens. The softened decal begins to “brittle up” in anticipation of the burn-off period.

480-800° F (250-430° C)

Organic covercoat and printing mediums burn off. Ventilation is very important at this time to insure that the organics are removed from within the firing chamber.

750-1063° F (400-573° C)

Nothing much happens Only pigment and flux powders remain (unfused) on the surface of the glaze. This is why an under-fired decal will wipe off after firing.

1063° F +(573° C +)

Quartz Inversion Temperature. Everything with quartz in it (which is pretty much all ceramics), contracts and expands. At around this temperature the firing speed of the kiln should be slowed down.

1063° F to maturity (573° C +)
(maturity depends on the ware, not the decal)(see Firing Fundamentals link)

Vitrification begins. Fluxes begin to transition into a glassy phase as they melt. The glaze softens under the decal sooner due to the influence of the fluxes, and the pigments fuse to the ware. Note: Glass decals are manufactured with lower temperature fluxes that begin this transition much earlier than overglaze and inglaze ceramic decals.


What about food safeness?

This is a really good question. Practically speaking, it’s a non-issue. Most decals from the last 20 years have been using low lead color palettes. Moreover, I have never personally heard of someone becoming ill or dead from eating off a fired decal. They have been eating off of them for centuries.

- Technically, unless a vendor can produce a certified toxicologist’s report indicating what the lead and cadmium levels are, they are unknown, and because they are unknown, one should not use that decal on food bearing surfaces.

- This is why you will often see the following warning:

WARNING: Do not use decals on surfaces that come in direct contact with food or drink. Some colors in decals may contain lead and/or cadmium. Keep decals away from children unless properly supervised.
On cups and mugs leave at least 20mm between the top of the rim and the decal. Conforms to ASTM D-4236. Contact physician for more health information.

- This warning is NOT because there is a specific danger present, but because the particular decal in question has not been tested by a toxicologist.

- This is more than a technicality. There is no other way around it!! Lead Testing Kits are not a legal substitution for a toxicologist’s report. Nor will firing hotter work. Firing hotter will in fact sink the colors deeper into the glaze, but the resulting lead and cadmium levels are still unknown. Nor will the assurances of a decal vendor that “their designs use unleaded colors” work. Without documentation from the color manufacturer, it is a worthless affirmation. Moreover, if any of the colors on the palette are low lead, printing them with unleaded colors voids the warranty (much like using unleaded glaze with low lead glaze).

- The CPSC (Consumer Product Safety Commission) does allow several exceptions for untested decals.

            - Exterior decoration is typically A.O.K. (note the above 20mm mug requirement).

            - Interior decoration is O.K. if the piece is not a food use item (like a vase).

            - Decorating the rim area of a plate is O.K. (because the food use area is primarily in the center).

            - Drilling a hole in the center of the ware so that it cannot hold liquid allows the use of untested decals (which, of course, everybody wants to drill a hole in their ware).

            - A permanent marking on the bottom of the ware indicating “Not for Food Use. Colors may poison food” allows the use of untested decals. This is what the Collector Plate companies do.

- I am aware of conflicting statements from various companies. You will have to decide for yourself. I say, “don’t do it”, but not because I am fearful for your life. As said above, really it’s a non-issue. But because I know of NO ONE who is certifying their patterns via a toxicologist, I must say, “don’t do it”.

Do you always have to fire a Ceramic Decal?

Another excellent question! This is where many people are surprised to find out that Fired Decals make wonderful non-fired decorations.

- The gum underneath the decal that helps it stick to the ware before it is fired also will make that decal stick very tenaciously to any smooth surface. How long? Indefinitely, if there is no abrasion or moisture applied to it.

- You can apply fired decals over candles, soap, plastic, metals, furniture, computer parts, wood, glass, vinyl, acrylic, Plexiglas, ceramics, polished stone, laminated papers, high gloss wall paint, mirrors, etc.

- You can also Decoupage with any fired decal using any of the store-bought sealers (like Modge Podge), or other sealers like polyurethane, clear brushing lacquer, or clear acrylic (brush on or spray on). Always let things dry thoroughly between coats.

- Furthermore, fired decals never fade in non-fired applications (altho the covercoat might discolor or pick up dust over the years). This is where a polyurethane sealer can make them VERY durable.


What other ways can you use a Ceramic Decal?

                            With Gold
             - as a accent near the decal (and in the same firing as when the decal is being fired)
             - as a accent  on top of decal (as a 2nd firing, after the decal has been fired on first)

        On top of a pre-fired background
            - air brushed background
            - sponged background
            - spatter brush background
            - speckle-tone glaze
            - other pastel gloss or satin glazes

                     With China Paints
  (fire decal, add china paints, fire again)
            - fill out background
            - connect decals
            - add accents
            - correct mistakes and blemishes

                 On Porcelain Bisque
            (polish bisque thoroughly
                   before mounting)

    On glass that is going to be sagged

            - Opaque decals look best
            - Non-Opaque decals do not look good on colored glass
            (note: we are talking about using a regular ceramic decal on sagged glass, not a glass decal. Glass decals MUST be fired at 022, whereas sagging is done at hotter temperatures.)

                 APT - II Techniques
            (see instructions below)

            - On greenware
            - On ceramic bisque
            - On texture glazes
            - Silk screen decals on glass fired at Cone 022
            - Reversing



1) - Clean greenware as normal.
2) - Prepare a solution of ½ water and ½ white hobby glue (e.g. Elmer's glue or equal). Or, use APT-Il Ceramic Enhancer straight out of the bottle (an excellent product).
3) - Sponge or brush on two thin, even coats of either solution onto the area where the decal is to be applied. Allow to dry between each coat.
4) - Apply a third coat and put decal in water so that it will be ready to apply (see "APPLICATION" Section).
5) - Before the third coat is dry (i.e., while it is still a little tacky), apply decal to prepared area.
6) - Carefully blot decal with a paper towel or cloth to remove bubbles and smooth out decal. Do not squeegee.
7) - Allow to dry for 24 hours.
8) - Fire with your next greenware firing (cone 04-06).
9) - Spray a matte or gloss sealer to protect from being soiled.

Note: Because of the higher temperature, some colors will fade significantly (usually Yellows, Oranges, and Flesh Tones). Earthtones will stand-up the best (Blues, Browns, and Blacks). Reds, Greens, Pinks and Purples will alter depending on the manufacturer; sometimes staying true, sometimes darkening, sometimes fading.

 Note: You can also fire decals on Ceramic Bisque, and on "Satellite", "Astro Gem", "Sand Star", "Galaxy", and "Gem Stone" glazes. Just use the above procedure plus put an additional coating of solution on top of the decal after it has been mounted. Also, fire at normal decal temperatures (cone 017 - 018).

 On Porcelain Bisque you do not have to use a surface prep. Just polish the bisque very thoroughly before you go to mount the ceramic decal. It should mount and fire just fine (cone 015-16).

 Note: You can also fire ceramic decals on pieces that have been glaze-fired and re-fire at cone 06 (as a third firing).You do not have to use a surface prep as described above. Just mount and fire as normal (except at the hotter cone). You will still get the same color variations as described above, and also, the edges of the design will mute (become less sharp & defined), as the color pigments tend to migrate out into the glaze at high temperatures. This is often a desirable effect as it makes the piece look antique.


Can you make a Ceramic Decal on a computer printer?

Yes and No.

- Inkjet printer decals will fire away, nevertheless, some people use them for non-fired applications or for “comping” (decorating a sample to see how it will look). Also, because they are printed with organic colors, they will fade with time and exposure to direct sunlight.

- Laser Jet decals can be fired at glaze temperatures because some of the pigments have a small amount of an inorganic component which can withstand the heat. However, because the colors are unfluxed (they have no powdered glass to help the glaze melt), they will rub off if fired to overglaze temperatures. Note: the resulting glaze-fired decal isusually gray or sepia in color with muted edges.

- There IS a specialty copier made in Germany that uses overglaze colors to print with, but these machines are expensive ($50,000), and the fleshtones are seldom satisfactory. (So much for portraits.)(But half-tone grays can look pretty good!)

- In all cases, a specialty paper must be used, and in all cases, a method of covercoating the decal must be used (like silk-screening or spraying on acrylic sealer).


what if I want to make a Ceramic Decal?

You will need 2 things: An understanding of how to do silk-screen printing, and, access to decal paper, printing media, overglaze colors, and a covercoat media. Frankly, unless you want to go into the business or if you are already a silk-screener who wants to experiment, put it out of your mind. It’s more trouble than it’s worth.

- A good beginner’s book for silk-screen printing is “Elementary Silk Screen Printing” by ALBERT KOSLOFF.

- Suppliers for decal components may be found on the internet. Do searches under “overglaze, ceramic, decals, covercoat, colors, printing” in various combinations.


What if I want to have a Ceramic Decal made for me?

3 things will determine your price:

1) Size of the design

2) The number of colors required to duplicate your artwork

3) The quantity to be printed (see Powers of Ten to the right)

These 3 factors make up what is called the “Price Matrix”. All printers have their own Price Matrix, sometimes published, sometimes unpublished.

- You will typically need to send them the original art, or, a computer scan on CD (300 dpi; TIFF format or as otherwise requested) to get a precise price. Often you will get hit with art charges or proofing charges (So camera ready art saves you money).

- There are at least a dozen domestic printers out there who specialize in fired decals. Find them on the internet, or look for their ads in Fired Arts and Crafts magazine.

Which company do you recommend for Open Stock Decals?

INSTAR, of course. They do all things well. Go to instardecals.com and enjoy. PS – They are also pretty price competitive on Custom Decals if you need more than 1000 pieces (for under 200 pieces, stay with the above mentioned domestic printers). And because they import from mostly European Manufacturers, their quality is best of the best as well.

Powers of 10

Rule #1 - Pricing and Delivery are a function of Quantity

Translated: How much you order in a single order will affect how much you will pay and how long it will take to get your decals. Interestingly, this may be broken into 6 groups based on powers of 10.

                   Hobbyist Level

Keyword: Flexibility

Typical Quantity: 1 to 9 decals
           (Open Stock designs only)

Uses: Special project; experimentation; fun; personal use; (sample piece for test marketing)

Pricing: Normal retail prices

Delivery: 1 to 2 days upon receipt of order

              Small Business Level

Keyword: Business Account

Typical Quantity: 10 to 99 decals
            (Open Stock designs only)

Uses: Regular repeat customer wanting to maintain inventory control by frequent ordering

Pricing: Normal retail prices less Trade Discount (one must usually provide a tax # and other business identification in order to qualify for a Trade Discount)

Delivery: 1 to 2 days upon receipt of order

           Small Manufacturer Level

Keyword: Discount

Typical Quantity: 100 to 999 decals
        (Open Stock or Custom designs)

Uses: Allows a manufacturer to order smaller quantities in order to keep finished ware inventory at optimum efficiency; extra discounts may be  available if decal vendor is allowed a longer lead time to deliver a decal order (this depends on the decal manufacturer of a particular design AND the size of the order); partial shipping of negotiated purchase orders.

Pricing: Normal retail prices less Trade Discount less negotiated or delivery discounts

Delivery: 1 to 2 days upon receipt of order, or, 2 to 3 weeks upon receipt of order

               Custom Decal Level

Keyword: Exclusivity

Quantity: 1000 or more pieces of a
              particular size of a pattern

Uses: Allows a manufacturer to have copyrighted exclusivity for a new design, or, allows a manufacturer exclusivity to a specially designed size of an existing pattern; substantially reduced prices on any size of an existing patterns if the order is placed prior to next printing of that pattern.

Pricing: Negotiated

Delivery: 4 to 6 weeks

          Large Manufacturer Level

Keyword: Quantity

Quantity: 10,000 or more pieces of a
              particular size of a pattern

Uses: To obtain best prices on an Open Stock design; to obtain better prices on Custom Printed designs; partial shipping of negotiated purchase orders.

Pricing: Negotiated

Delivery: Call for verification of inventory on hand vs. inventory set for next printing

              Mass Producer Level

Keyword: Expedited

Quantity: 100,000 or more pieces of a
               particular size of a pattern

Uses: Custom order of an exclusive design for large scale production

Pricing: Negotiated

Delivery: “Best Way” - Typically drop-shipped from factory, or, landed at the manufacturers agent and re-sent by common carrier.


(see also the Kinds of Decals link)

                 Open Stock Decals

"Open Stock" is a term used to describe decals that are already printed from which you buy as many or as few as needed.

                    Custom Decals

This is a decal that has been printed just for you.

                  Expedited Decals

This more indicates the supply chain status of a pattern than it does the kind of decal. Expedited Decals are always Custom and in large quantities.

                     Glass Decals

A decal that is meant to fuse and mature at Cone 022. Aka. Low Fire Decals

        Fired decoration of glassware
            - Fire at Cone 022 on soda-lime glass (most glassware)
            - Fire at Cone 021 on borosilicate glass (cooking ware, e.g. Pyrex)

        Fired decoration of ceramics,
       porcelain, and enameled metal
            - Fire at Cone 022 on any surface that can withstand 1040°F        

      Non-Fired decoration of any hard
                   or firm surface
            - Can be sealed with a clear finish such a lacquer or acrylic.
            - Doesn’t need to be sealed if surface is especially smooth.
            - Also can be used on candles and soap.

                  Organic Decals

A newer type of decal that is not meant to be fired. It is made from organic, lead- free colors. Similar to Dye-Sublimation Decals except it is water-mounted and is air cured. Aka. Kitchen Oven Decals; Low Temperature Decals

      Non-Fired decoration of any hard
                    or firm surface
            - May be left intact on decorated surface
            - May have cover-coat peeled off after drying 24 hours
            - May be fused at low temperatures (300°F for 20 minutes)
- Dishwasher Safe, but will scratch and fade over time

                  Ceramic Decals

Decals made from overglaze colors (China Paints) Aka. Water-mount overglaze transfers, Fired Decals

      Fired decoration of ceramics and
            - Fire at Cone 017 to 018 on Hobby Ceramics and Terra Cotta.
            - Fire at Cone 015 to 016 on Stoneware and Decorative

      Non-Fired decoration of any hard
                   or firm surface
            - Can be sealed with a clear finish such a lacquer or acrylic.
            - Doesn’t need to be sealed if surface is especially smooth.
            - Also included are candles and soap.
            - “One Fire” decorating of glass that is being slumped at Cone 016 or 015 (Just apply decal onto ware to be slumped, let dry for 24 hours, and slump)

              Heat Release Decals

Specially made ceramic decals that are meant to be machine mounted.

For production manufacturing using specialized equipment / Custom designs only

                  Inglaze Decals

Decals printed using Underglaze Colors.

       For decorating ware at glaze

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