Application Stories

Since 1973, Dynacept Corporation, a rapid prototyping and conventional model-making company, has been providing services including stereolithography to a variety of industries.

Human Factors Industrial Design, Inc., a research, design and engineering firm that assists Fortune 1000 companies, uses Dynacept's expertise to produce prototypes for various industries, including consumer product OEMs.

Recently, Human Factors sought Dynacept's assistance in developing a product for a company that distributes cosmetics exclusively to upscale department stores. The company needed a new mascara brush applicator design which would eliminate a common problem "clumping." With traditional mascara brush applicators, liquid mascara tends to dry into clumps on the brush, causing users' eyelashes to look unnatural and cakey after application. To solve this problem, Human Factors designed a non-brush applicator with comb-like qualities. The newly modeled applicator literally combs the lashes while applying the mascara, reducing the chances of clumping.

The Challenge: Finding a Non-Soluble Prototype Material
To produce an accurate prototype applicator, Human Factors used stereolithography (SL). The wall sections of the prototype were four thousandths of an inch thick, and were separated by distances of one hundred and twenty thousandths of an inch. Traditionally, applicator prototypes are tested in water and other solvents for up to a week. Since the walls of the prototype were so thin, the resin often softened and warped when it was left in an aqueous solution. Human Factors had to order two to three times more parts than would have been needed with a more moisture-resistant resin.

The Solution: Somos 7110 Withstands Aqueous Conditions
Dynacept solved its prototype failure problem by using a new epoxy resin, DSM Somos 7110. With good throughput definition, Somos 7110 offers more robust processing parameters than other resins. According to Matt Cantwell, manager of rapid prototyping at Dynacept, Somos 7110 prevented Human Factors' parts from failing during liquid testing. DSM has taken most of the best characteristics of all of the resins on the market and consolidated them into one superior product."

Bert Heinzelman, vice president of Human Factors, agrees that Somos 7110 resin outperforms competing products. DSM Somos 7110 does not soften when immersed in water," says Heinzelman. "In developing a new product that will be exposed to water, we are now able to conduct realistic tests with components produced by stereolithography using Somos 7110."

Dynacept is also using Somos 7110 in other prototyping applications including physical flow testing, rubber molding prototype production, and chrome-plated models. "We are really happy with the high humidity capabilities and scan speed of Somos 7110," says Cantwell. "Somos 7110 scans twice as fast as competing brands of SL resins. We are totally committed to using it."

For more information about Dynacept Corporation, call 914-241-3520; Human Factors, call 212-868-2277

For further information on DSM Somos:
Melisa Lasell < Europe@dsmsomos.info>
DSM Somos® External Affairs Europe
Via della Stazione 7F
00042 Anzio (Roma), Italy
Tel. ++39.06.986.5179
Cell. ++39.339.526.3828