Ceramic Industry

PPP - Decorating For Success

May 11, 2000
The need to meet customer requirements and exceed their expectations compels the development of new products and the improvement of existing ones.

One tool that a manufacturer can use to differentiate its products in this challenging and competitive marketplace is decoration. Glazes, pigments, underglazes, overglazes, decals and “ceramic ice” can all contribute to a product’s uniqueness, and combinations of these products allow decorators to further expand their palette.



As the new millennium approaches, small ceramic manufacturers in the U.S. are facing challenges that threaten their very existence. An ever-increasing number of regulations tax the limited resources of many manufacturers. One such regulation is the new PBT (Persistent Bioaccumulative Toxins) regulation proposed by the Environmental Protection Agency (EPA), which could cost affected businesses over $7,000 annually if they use just 10 pounds of lead. Additionally, the challenge of lower-cost overseas manufacturers, unburdened by environmental and labor regulations, makes increasing productivity and minimizing waste a priority for today’s domestic manufacturers. The need to meet customer requirements and exceed their expectations compels the development of new products and the improvement of existing ones.

One tool that a manufacturer can use to differentiate its products in this challenging and competitive marketplace is decoration. Glazes, pigments, underglazes, overglazes, decals and “ceramic ice” can all contribute to a product’s uniqueness, and combinations of these products allow decorators to further expand their palette.

Glazes and Decorating Techniques

The glaze is the thin coating on a ceramic body. It consists of a silicate-based material with fluxes and modifiers. A successful glaze fits the body well, with a coefficient of thermal expansion approximately 10% lower than that of the body.* Glazes are usually classified as gloss, semi-gloss, semi-matte and matte. Formulations for some lead-free gloss base glazes at different firing temperatures are shown.

Careful preparation and testing are necessary when establishing a new base glaze. Several laboratory batches of the more popular colors should be prepared, applied and fired to verify that the proper glaze/body relationship has been developed.

After a base glaze has been established, it should serve as the workhorse for most applications. Larger batches of the base glaze should be produced and tested for suitability. The manufacturer should then use dispersible ceramic colors to produce colored base glazes. The use of dispersible glaze pigments reduces final cost since it requires fewer mill changeovers, and therefore reduced waste.

These base glazes can then be blended in biaxial and triaxial combinations to produce intermediate colors. By controlling the number of colors used in the facility, the manufacturer can control its inventory and ultimately, its costs.

The base glaze, base colors and ceramic body can be successfully blended to produce a compatible series of underglazes. Substituting 325 mesh flint or an opacifier for a portion of the ceramic color can control the color intensity of the underglaze. Several underglaze formulas are shown to illustrate this effect.

Overglazes are a blend of lower temperature fluxes, pigments and an application vehicle. They require an additional firing cycle, which, while it does add cost, allows decorators to add bright reds, oranges and purples to their palette.

Commercially prepared overglazes offer the manufacturer a ready-to-use system of colors that are intermixable to produce a wide range of colors. The main advantage of this type of system is that off-the-shelf color matches can be obtained from the system manufacturer.

Decals are another way to add color and decoration to ceramic products. While they require an additional firing cycle, they offer the ability to produce and reproduce intricate patterns, corporate logos and other unique special effects. The main drawbacks to decals are the inventory cost and storage requirements. However, decal suppliers and decal component manufacturers can advise you on the decal system or systems that will work best for your company.

Ceramic ice, another decorative technique, allows a decorator to achieve a three-dimensional effect on the product. The “ice” is a sized frit product that is commercially available in a number of particle size ranges and firing temperatures. Usually applied over a fired surface, the “ice” fuses with the glaze but does not melt entirely into the surface. This raised effect can be used alone or in conjunction with other decorating techniques, further expanding the manufacturers’ ability to offer unique products.

Improving Your Bottom Line

By using some or all of the previously mentioned decorating tools, a manufacturer can expand its offerings to the marketplace. However, to improve your bottom line, other areas must be addressed. These include reduction of glaze defects, consistent product quality and regulatory compliance.

Glaze defects can be caused by a number of factors. Many books and papers detail common glaze problems and their solutions.* Additionally, a cadre of ceramic engineers with extensive experience in problem identification, root cause analysis and systematic solutions are available on a consulting basis. With the continuing reduction of the number of in-house engineers, consulting with one of these professionals may be the ideal solution for some companies. Besides analyzing glaze defects, these consultants can identify a number of ways in which a manufacturer can reduce waste, and can also help train existing staff how on to identify and document key operating parameters and how to correct minor situations before they become major problems. Consultants can also impart new technologies to your staff and create new opportunities for growth and learning.

Regulatory compliance can be obtained in two ways. The more desirable method is being proactive, working with agencies such as the Bureau of Worker’s Compensation Industrial Hygiene Division in Ohio. This type of agency seeks to assist the manufacturer in setting up programs to reduce worker exposure to on-the-job hazards. It also can help in demystifying compliance with regulations. Private compliance firms are also available to help manufacturers.

The other form of compliance results from working with enforcement agencies, and usually comes with a higher price tag in terms of fines and penalties for being out of compliance. Enforcement agencies sometimes have consulting branches that do not fine a manufacturer but do have defined timetables for coming into compliance. Some individual regulators, especially those with some state agencies such as the EPA, can offer constructive suggestions on ways to become and remain compliant. Regardless of who you work with, all regulatory personnel should be treated with courtesy and respect.

The challenges of the future can be rewarding to those manufacturers that investigate new technology, offer new or improved products, and improve internal systems. Manufacturers that invest in themselves and their employees will benefit from the opportunities available in the years to come.

Footnote

*W.G. Lawrence and R.R. West, Ceramic Science for the Potter Chilton Books, Radnor, PA, 1982, pp. 179-183.

For More Information

Contact Earl Breese, General Color & Chemical Co., P.O. Box 7, 604 Valley St., Minerva, OH 44657; (330) 868-4161; fax (330) 868-5880.

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