It was developed in the United States, but now technology to extrude sheet for plastic eyeglass frames is leaving the country.
Tectonic Industries Inc. has shut the doors of its plant in Berlin, Conn.
Charles Merritt, who founded Tectonic in 1964, sold the company in early 1996 to an Italian competitor, Mazzucchelli 1849 SpA.
A year later, he began winding down production. Tectonic extruded its final eyeglass sheet July 31.
Tectonic extruded sheets of cellulose acetate, like colorful works of art for the eyeglass industry, which in turn were sold to frame manufacturers.
Even when wire-rims became the frame of choice for prescription eyeglasses, there was the plastics oriented, high-end sunglass industry — but it wasn't enough. Foreign competition, Merritt said, marched on as sheet extrusion technology followed more labor-intensive frame assembly to Hong Kong and China.
Merritt, 68, said Tectonic did not have the resources to open its own plant in the Far East. That meant the end was almost inevitable, he said. Mazzucchelli is moving the machinery from Connecticut to its headquarters in Castiglione Olona, Italy, and its own plant in China.
``We had seven lines for optical. You can't imagine. To watch a business you built disappear and not be able to do anything about it, is just devastating,'' Merritt said.
Meanwhile, a designer at Ray-Ban sunglass maker Bausch & Lomb said losing the last U.S. source for frame stock will make it more difficult — and expensive — to get samples to create new frame designs in the United States.
``What it means now is any product that's going to be manufactured in the U.S., we have to import the material now instead of getting it directly,'' said Mark Flanagan, Ray-Ban design manager. ``So now you're paying more for shipping and freight.'' Also, lead times are longer because it takes longer to ship the sheet.
Tectonic's name is now the U.S. Division of Mazzucchelli, doing business as Tectonic Industries Inc. Merritt will remain as president of the U.S. Division. He also will keep running a second plastics business, Merritt Technologies Inc., which employs 40 in Berlin. The firm extrudes and laminates for the signage and engraving markets, such as nameplates for desks and office doors. The company also extrudes sheet for safety goggles and shields.
At its peak, Tectonics employed 145 and ran seven days a week. When Merritt sold to the Italians, about 50 people worked there — then the slow shutdown began.
Early plastic frames were fashioned from cellulose nitrate.
``That was a highly flammable material and was made through what was commonly called the block process,'' he said.
Under the block process, also called a ``wet process,'' cellulose nitrate was softened by mixing it with solvents and a plasticizer, camphor. Then it was extruded and run through roll mills. The resulting stock went into a compression molding press.
``A block was formed that measured approximately 24 by 54 by 8 inches thick,'' Merritt said.
The big block was fused to a steel plate, which was bolted onto a machine that cut off thin sheets, like a razor blade. The sheets were put in special drying areas to remove the solvents.Blanks for early plastic combs also were made by the block method.
A development in 1955 made block slicing obsolete. That year, Merritt said, Rowland, Eastman Kodak Chemical Co. and American Optical Corp. jointly developed multicolor extrusion of cellulose acetate sheet for eyeglass frames.
Extrusion ``brought extremely short delivery times as opposed to waiting six months. We also eliminated the flammability problem and we got much longer color life. The old nitrate frames would turn yellow in six months.''
Extrusion, like block process before it, turned out patterns in cellulose acetate plastic frames, like tortoiseshell and mother-of-pearl. Tectonic extruded the sheet in strips as wide as 8 inches, of any length. The company also did laminating and compression molding.
To cut frames, frame makers used a pantograph, a machine that has a stylus on one arm and a cutter on another arm. The cutter follows a shape traced by the stylus. Computer-controlled machines do the work today.
Flanagan described how to make sunglass frames from the plastic sheet: The part that holds the lenses, called the head curve, is heat formed into its curved shape.
``The temple's heated up and the wire's just shot in there'' in a machine, he said.
Hinges are inserted by a machine, and the frame is finally assembled by hand.
Merritt said the U.S. companies that pioneered multicolor extrusion sold the process to firms in Germany, Japan, India, Britain and other countries.
Merritt founded Tectonic with three partners.
``In 1964, when we started in business, we had 55 frame manufacturers in the United States. By March of 1996, we were down to seven customers in the U.S.''
But Merritt said the future was obvious by 1978 — the year Tectonic started selling sheet overseas.
Hong Kong competitors, with their low labor costs, could sell frames for one-third the price of a U.S.-made frame.
``We could see the handwriting on the wall. The frame manufacturing business was a very labor-intensive business. From '78 to '81, we had more business than you could imagine. We really were sold out. Most of our volume was heading for Hong Kong at that point. The growth in the Hong Kong area was just absolutely unbelievable.''
German makers also fell to the Asians. In the late 1970s, Germany had about 30 frame manufacturers. ``Today they're all gone,'' he said.
Italy, a leading country for frame design, remains the only major force in Europe in sheet extrusion and eyeglass frame production, according to Merritt.
Plastics also got hit by a resurgence in metal frames, starting in 1988. From experience, Merritt knew that the pendulum would swing back and forth from plastic to metal, but this was different.
``This time, the metal frame manufacturers developed a way to add color to the metal,'' which took away a big advantage for plastics.
That left the high-end sunglass market, which still has some U.S. manufacturing.
Bausch and Lomb makes sunglasses at company-owned factories in Hong Kong; Waterford, Ireland and San Antonio. The company is shutting down its frame operation in its headquarters in Rochester, N.Y., and moving it to San Antonio.
Flanagan, the Ray-Ban designer, said the company will continue buying sheet from Tectonic/ Mazzucchelli.