Celanese Corporation is an American chemicals manufacturer. Celanese plastics are known to have been used by two keyboard manufacturers.
Celanex is Celanese’s PBT (polybutylene terephthalate) resin family.
As the Celanese Plastics and Specialties Company (trading as Celanese Engineering Resins), Celanese supplied Celanex 2012 to ITW Cortron for their SS3 solid state keyswitches. The advertisment describing this was used to identify SS3. The advertisement notes, “need dieletrics – use Celanex 2012”, with the suggestion that Celanex 2012 was used for the body of the switch, as there is no separate lead carrier in SS3 as there was in the previous Series 54. The advertisement explained:
CELANEX 2012 – recognised as meeting U.L. 94V-0 and as a Class 130 material on the U.L. electrical temperature index – provided excellent mechanical properties and flexibility, superb dielectrics and exceptional consistency in both performance and processing. It also offered the necessary chemical resistance to the powerful solvents used in degreasing.
As Celanese Engineering Resins, they advertised Celanex 2000-2 unreinforced thermoplastic polymer in the 15th of June 1984 issue of Computer Design magazine. Celanex 2000-2 is described as a hard-wearing heat-resistant plastic particularly well suited to computer keycaps, and ideal for dye sublimation legend printing. The advertisement states:
Printed Celanex® keytops eliminate costly, time consuming two-shot molding processing, providing wear resistant, multi-colored lettering capability. These features, combined with outstanding processing characteristics, are why Hewlett-Packard selected Celanex® 2000-2 for the terminal keytops of their HP 150 Touchscreen Personal Computers. Quality demands quality. Celanex® 2000 series thermoplastics offer a unique combination of printability, chemical and wear resistance, dimensional stability, strength, stiffness and surface gloss to withstand the tests of time. In fact, the molding experts at Hewlett-Packard report Celanex® 2000-2’s internal lubricant system facilitates mold release without mold plate-out–maximizing productivity.
The keyboard depicted in the advertisement is identical to keyboard models 46010A and 46011A, except for the lack of moulded HP logo.
Celcon is an acetal copolymer. Celcon was advertised at the same time as Celanex 2012, also being used in ITW’s SS3 keyswitch. Two parts are marked as being made of Celcon, suggested to be the lid and the plunger shaft. However, the plunger shaft is the same moulding as the base, although the lid does enclose the plunger shaft. However, there is no way to be certain as there is no available copy of the advertisement in good condition and the finished switch differs somewhat from the depiction in the advertisement.
With regard to the material, the advertisement writes:
CELCON acetal copolymer provided the inherent lubricity and remarkable long-term stability demanded by a snap-fit application in a moving part. Both resins were dimensionally stable in extreme environments including high temperatures and humidity and both were simple and economical to process.
- Celanese Plastics Co. Celanex advertisement, Electronics, Vol. 46 No. 20, September 27 1973 (scanned by or for WorldRadioHistory.com)
- Celanese Celanex 2012 and Celcon advertisement (featuring ITW Cortron SS3), Plastics Design and Processing, Vol. 19 No. 11, October/November 1979 (obtained via the Internet Archive, and converted to PDF)
- Celanese Engineering Resins Celanex advertisement, Computer Design, June 15 1984, p. 68 (scanned by Bitsavers)