Solomon Colors

With its computer-based liquid coloring system, Solomon Colors assumed a lead role in using technology to make life better for the concrete industry. Even the concrete truck drivers like it!

by Susan Brimo-Cox

Solomon Colors is the largest U.S.-owned producer of iron oxide pigments. Based in Springfield, Ill., the company got its start in the 1920s. Robert C. Solomon, the operator of the Panther Creek Coal Mine Co., decided that the black, carboniferous slate that lies above the coal seams would make a good color by-product. Solomon Grinding Service got its start grinding the slate from the mines, as well as red iron ores from Michigan and yellow ochres from Georgia.

For some 50 years, SGS operated as a toll or contract manufacturer, its products sold by others. But in 1970, Solomon Colors began marketing its own name brand products. Then in 2000, the firm sold its pulverizing mill division to focus on color. Rich Solomon, vice president and grandson of the founder, explains that when the company was started it used 100 percent natural iron oxides. Today, 90 percent of the color pigments Solomon Colors manufactures are synthetic iron oxides. And its colors come from around the world — from countries such as China, Brazil and Poland — in addition to various locations in the United States. From a basic combination of four iron oxide colors — yellow, two reds and black — Solomon Colors has expanded its color catalog to more than “500 standard pigment shades and over twice that number have been made for architects and contractors wanting a special color,” Solomon says.

Good techniques are key to success with integrally colored concrete
The minute you add integral color to concrete, people look at it differently than they do gray concrete — their expectations are higher. Educating your client about integral color is important. Be sure to explain its limitations. But, also, be sure to use good techniques. These contractor-recommended tips can help ensure excellent results:

— Make sure the sub-grade is evenly saturated, otherwise discoloration may occur.
— Find a reliable ready mix producer and work as a team.
— Make sure the design mix is duplicated exactly for consistency in multiple pours (i.e. stick with one brand of cement, one source of sand and aggregate, the same amount of water and admixes, etc.).
— Be aware that weather plays a role in the results. Don't pour if rain is expected within 24 hours. Pay attention to temperature and humidity conditions.
— Use a wood bull float instead of a magnesium bull float. A wood bull float lets bleed water evaporate. A magnesium float can seal up water, which can cause discoloration.
— Integral color is good as is, but you also can achieve aesthetically pleasing finishes by exposing the sand and aggregate in the mix.
— When applying a broom finish, be sure to change your broom — instead of rinsing it — when material buildup occurs. Extra water deposited by a rinsed broom can cause discoloration.
— Never spray water on the surface during the finishing stage.
— Proper curing is important in ensuring consistent color.
— Don't use plastic to cover integrally colored concrete. Condensation on the underside of the plastic can discolor the concrete.

Finding success with liquid color
Integral color has always offered ready mix producers and contractors a good mark-up opportunity. But while dry pigment can give you very uniform color, it has its disadvantages and liability can be high. So, in the late 1990s, a team at Solomon Colors set out to use technology to make integral color easier and reliable. Bill Dube, general manager of Solomon Color’s Pacific Division, was part of the team, which also included systems analyst Mark Gray, company chemist Steve Brown and Vice President of Production Charles Kreutzer. Dube says the idea of liquid color pigments was not new — a system developed a decade earlier by another company failed. What made Solomon Color’s ColorSelect System different was that it was specifically designed with the ready mix producer in mind.

In 1998, the first two ColorSelect systems were installed in southern California. “We started with a programmable logic controller, which evolved into a PC-based system,” Solomon explains. “In the beginning it was a hard sell — there were skeptics. [But] the system has also made converts to integral colored concrete.” Both systems are still out in the marketplace, but the PC system has additional advantages, including the ability for a Solomon Color technician to access a ready mix producer’s ColorSelect computer via modem to deliver a custom formula. Today there are nearly 90 of the systems in use. “Liquid is not a miracle pigment. What the liquid system has done is give ready mix producers verification. The system does all the calculations, and the operator can see from the printout exactly what went into the truck,” Solomon adds.

Since its debut, Solomon Color’s ColorSelect product has been used in many residential and commercial projects — in flatwork, cast-in-place and tilt-up applications — including high-profile projects like the Stardust Casino, Caesar’s Palace and the MGM Grand Hotel in Las Vegas, as well as Autopia at Disneyland, reports Dube. “We’ve done thousands of cubic yards with this system with very little trouble. We’ve taken as much human error out of [the process] as possible,” he observes. “The design mix is documented. It makes everyone accountable — the ready mix producer, the contractor and the homeowner.”