Ingemar: To determine if Marianne's suggestions are correct, in my experience, the best way would be to perform thermodynamics analysis on the materials. A thermomechanical analysis (TMA) will tell you Tg, as well as give a feel if the material is properly cured if the correct techniques are employed during the analysis. Residual stresses can also be found using DMA; TGA analysis might be helpful if you have a hydroscopicity problem causing registration losses... Regards, > Bill Davis, Ph.D. > Diamond Multimedia Systems > Senior Scientist > Tel. 408.325.7868 > Cell. 408.888.5650 > e-mail: [log in to unmask] > > > > > -----Original Message----- > From: [log in to unmask] > [SMTP:[log in to unmask]] > Sent: Thursday, November 19, 1998 11:43 PM > To: [log in to unmask] > Subject: Re: [TN] THERMOPLASTIC RELIABILITY > > >Thanks for answer, Marianne, > I will ask the manufacturer as you indicate. Werner Engelmaier is of > different opinion. He thinks we exaggerate the problem. Huge and heavy > and complex structures are being built with thermoplastics, and they > keep adhesion despite hot ambient conditions. Thanks again.//Ingemar > > -------------------------------------------------------------------- > No optimism here. > > > > If the maximum Tg is 75 C, it is quite possible that the beginning > of > the > > glass transition zone is in the 60 C range. Softening and loss of > > positional registration can therefore occur. > > > > To verify whether this particular product is useable in your > operating > > environment, you may want to have the material analyzed to determine > where > > the onset of softening occurs, and to ask the supplier for their > > manufacturing process tolerances on the thermoplastic. Or run your > product > > through reliability testing. > > ____________________________________________________________ > > Marianne Romansky > > Process Development Scientist > > Celestica (Toronto) Inc. > > Phone: (416) 448-6284 > > Email: [log in to unmask] > > > > ################################################################ > TechNet E-Mail Forum provided as a free service by IPC using LISTSERV > 1.8c > ################################################################ > To subscribe/unsubscribe, send a message to [log in to unmask] with > following text in the body: > To subscribe: SUBSCRIBE TechNet <your full name> > To unsubscribe: SIGNOFF TechNet > ################################################################ > Please visit IPC's web site (http://www.ipc.org) "On-Line Services" > section for additional information. > For technical support contact Hugo Scaramuzza at [log in to unmask] or > 847-509-9700 ext.312 > ################################################################ > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################