Q: What are conformal coatings?
A: Conformal coatings are barrier materials typically applied in thin layers that provide chemical, mechanical and/or electrical properties and/or protection. Typically thought of in the context of electronics, conformal coatings are also valued components of biological, medical and industrial systems. Advanced Coating applications are in service from the depths of the oceans to the vastness of space.
Q: What conformal coatings do Advanced Coating apply?
A: Parylene (type XY), Urethane (type UR), Acrylic (type AR), some Epoxies (ER) & some Silicones (type SR)
Q: How are conformal coatings applied?
A: Parylene (XY) is applied at ambient temperature, using a vacuum deposition process. Urethane (UR) and Acrylic (AR) are spray applications. Silicone (SR) and Epoxy (ER) are flow applications.
Q: What national/industry standards do conformal coatings meet?
A: Conformal coatings for use on printed wiring assemblies meet IPC-CC-830B and MIL-I-46058C.
Q: Does Advanced Coating's quality management system meet any national/international standard?
A: Yes. Advanced Coating is registered to ISO9001:2008. We also maintain compliance to AS9100.
Q: My application is military and/or aerospace. Does Advanced Coating have experience in these fields?
A: Absolutely. Vast experience. Current and past customers include OEM's and a wide swath of Tier 1 and Tier 2 suppliers. Our applications protect guided munitions, landing gear, throttles, communications devices, spacecraft and deep sea submersibles.
Q: My product is ITAR controlled. Is Advanced Coating ITAR compliant?
A: Advanced Coating is ITAR registered. The registrant code is M26606.
Q: My application is both easily damaged during handling and ESD sensitive. How does Advanced Coating address these issues?
A: The safe handling of parts, the vast majority of which were not intended nor designed to be handled, is at the core of our competence. We illuminate and institutionalize any uniquely fragile conditions during the quote process. Our standard handling methods are designed to successfully process PWB's without damage. Our ESD program complies with MIL-STD-1686 & ANSI/ESD Association Standards.
Q: What sampling plan is used?
A: Typical inspection is 100%. If a sampling plan is necessary, a C=0 sampling plan with an acceptable quality level (ACL) of 0.65 is the standard.
Q: My parts have been cleaned before you receive them. Why would they require cleaning again?
A: The cleanliness of the part can significantly impact both the quality of the coating and the ability of the coating to adhere to the substrate. We must be absolutely certain the parts are clean before we coat the parts.
Q: What cleaning techniques are available?
A: Options include vapor degreasing, ultrasound, aqueous machine washing, plasma, IPA, DI water, various soaps and saponifiers, convection ovens and vacuum ovens in addition to a number of proprietary techniques. We tailor the method to the part.
Q: What masking techniques are available?
A: Standard masking conventions include liquid latex, non-ammoniated liquid latex, water soluble liquid latex, a large array of tapes, tape dots and any number of caps and boots of various sizes and configurations.
Q: What coating thickness do you recommend?
A: Naturally the thickness you require is in direct response to your end use requirements. Urethane (UR) and Acrylic (AR) thicknesses typically tend to be in the .002 - .004" range. Silicone (SR) slightly thicker. Parylene applications run the gamut from .2 microns to .005" plus.
Q: What is the Advanced Coating inspection protocol?
A: Receiving inspection confirms the identity and count of the receipt and will generally identify gross damage. As the parts move through the process they is inspected after each significant process step by the technicians performing the step. As each process is more detailed, so is the subsequent inspection more detailed. Additionally, independent inspectors evaluate the work after cleaning, masking, coating and perform final inspection.
Q: What is UV tracer and why is it a useful inspection tool?
A: Urethane (UR), Acrylic (AR) and Silicone (SR) include a fluorescing agent in their chemistry. Parylene does not. When inspected with UV light, UR, AR and SR coatings fluoresce brightly and clearly indicating where the coating has and has not been applied. Parylene does not fluoresce. UV tracers can be added to Parylene to that add a level of fluorescence.
Q: What is adhesion promotion and why would it be necessary? What types of adhesion promotion are available at Advanced Coating?
A: Adhesion promotion is a mechanical or chemical process that increases the strength of the bond between Parylene and the target substrate. Not unlike the difference between how paint adheres to the window jam but not the window glass, different substrates offer different levels of adhesion. Adhesion promotion levels the playing field. Options include micro-blasting, plasma and chemical promotion. While micro-blasting may be suitable for some metal or composite parts it's clearly unsuitable for PWB and other delicate items. Plasma activation and the vapor and/or liquid application of the industry standard A174 organosilane are available options.
Q: Can conformal coatings be reworked?
A: Yes and no. Each case is unique. In general, Acrylic (AR) can be chemically removed relatively easily and Urethane (UR) and Silicone (SR) less so. Parylene cannot be removed chemically. Parylene removal is mechanical via micro-blasting or plasma ablation. Both methods have significant potential downsides.
Q: It's easy to distinguish an uncoated UR or AR part from a coated part. The film thickness of Parylene makes it hard to tell if a part is coated or not. How does one distinguish between the coated and uncoated part?
A: Because of the way our process is designed and because 10's of thousands of Parylene coated parts pass through our hands annually, it's easy for us to know the difference. For our customers, the easiest way to determine if a part is coated or not is to look for a demarcation line; the point where a masked area and a coated area meet. Use of magnification is helpful.
Q: What are the typical lead times? Does the lead time vary by coating?
A: Once established, the standard lead time is 5 - 7 working days for all coating types. Expedited processing is available.