How can I determine how much board coverage I can achieve using HumiSeal's coatings?
This is a rough formula for estimating conformal coating coverage, based entirely upon a bare, unpopulated board and does not compensate for any transfer inefficiencies, components or wastage.
Metric Calculation:
In one Litre there are 1,000 cubic centimetres (1ml = 1cm3).
1cm = 10,000μm, therefore 25μm (approx 1 mil) = 0.0025cm.
To obtain the coverage, if the coating is 100% solids, you would divide the 1,000 cubic centimetres (1 litre) by 0.0025 - thereby obtaining coverage of 400,000 square centimetres at 25μm (~1 mil) thick.
If you are seeking a thickness of 50μm or 75 μm ( approx 2 or 3 mils) you would simply divide the 1,000 cubic centimetres by the desired thickness; i.e. 0.005 (50μm / 2 mils) = 200,000 square centimetres of coverage and 0.0075 (75μm /3 mils) = 133,333 square centimetres of coverage.
THE ABOVE ASSUMES 100% SOLIDS - TO COMPENSATE FOR THE SOLVENT LOSS YOU NEED TO MULTIPLY ANY OF THE ABOVE COVERAGE NUMBERS BY THE PERCENT OF SOLIDS CONTAINED IN THE COATING - AS FOLLOWS:
As an example; 1B31 is 35% solids therefore coverage at 25μm (1 mil) would be 140,000 square centimetres (400,000 x 35%), coverage at 75μm (3 mils) would be 46,667 square centimetres (133,333 x 35%).
This method will work for all of HumiSeal's coatings. The only variable is the percent of solids within the different coatings.
Does HumiSeal offer any conformal coatings that will enable our company to meet the new VOC requirements?
Yes! HumiSeal offers a full range of environmentally friendly Coatings. These Coatings have been specially formulated to retain their full reliability while addressing today's more stringent environmental regulations. HumiSeal offers Conformal Coatings and Thinners that are low in VOC's as well as a full complement of VOC free products.
Please contact SCH directly so that we may recommend the product which best fits your particular requirement
We are required to use a Conformal Coating that is UL recognized. Does HumiSeal have any UL recognized Conformal Coatings?
Yes. Many of HumiSeal's Conformal coatings are recognized under the Component Program of Underwriters Laboratories, Inc., File Number E 105698. The product tables contained on this web site clearly state which of our products meet these requirements.
You may also view a complete listing of HumiSeal's UL recognized Coatings on the UL web site. Once there simply insert HumiSeal's name into the company name space, hit search and Humiseal’s file will come up.
Our customer requires that we coat their boards with a Conformal Coating that is military qualified. Does HumiSeal have any coatings that meet the military specification?
Yes, in fact HumiSeal has more products qualified to the Military's MIL-I-46058C specification than any other Conformal Coating Manufacturer. The product tables contained on this web site clearly state which of Humiseal's conformal coatings meet these rigid requirements. You may also view the Military's Qualified Products List (QPL) for this specification on their web site
We have reviewed your web site and can find no mention of a Parylene coating. What is it and do you provide it?
Parylene, also known as Polyparaxylelene, is a very good Conformal Coating that applies by a vapour deposition process.
However Parylene is also a very expensive coating. Not only is the material itself expensive, the equipment required to apply Parylene is also expensive. Parylene is vacuum deposited onto the assembly, and one application cycle can require many hours to complete. Due to its cost and application issues, Parylene does not readily lend itself to large volume application and subsequently HumiSeal has chosen not to include it in our range of product offerings.
If you have an application where you feel that Parylene may be required, there is a strong possibility that another Coating may suffice at far less expense. Please contact SCH directly and allow us to assist you with a potential offset recommendation.
We are in the design phase of a new project and were wondering if you could provide us with the estimated cost of conformal coating a PCB assembly?
The cost of actually applying the conformal coating to the assembly will vary greatly by application method and projected volumes. The material costs for the Conformal Coating itself are very low and will normally be less than £0.001 per square inch of board surface for a 25um dry film thickness! This may vary slightly dependent upon the Conformal Coating used and can be further reduced dependent upon your purchasing volumes!
Overall, the application of a quality Conformal Coating is the cheapest way to insure the long term reliability of your printed Circuit assemblies!
Please contact SCH directly for further assistance in determining your actual Conformal Coating costs.
Are samples of your products available and how do I obtain one?
Yes! Samples of our products are readily available. Please contact SCH so that we may recommend the product which best fits your particular requirement
Are HumiSeal conformal coatings compatible with selective conformal coating robot equipment?
SCH and Humiseal work very closely with all the major manufacturers of selective robotic application equipment. As a result all of HumiSeal's coatings are compatible with the majority of automated application systems on the market.
For further information please contact SCH directly.
I want to apply a conformal coating to a PCB between 0.5mm and 1mm thick but I don't know what coating I need. Would there be a problem of trying to put conformal coating on that thick?What coating would you recommend and what is preferred application method?
Generally conformal coating are designed to be applied at 30-130 microns. If more then Humiseal will not guarantee the performance of the conformal coating on the end assembly. The reason for this is that all Military and IPC qualification are specifying this thickness and it is the thickness under which they have been tested.
The main problems you could see by applying so thick a conformal coating is solvent entrapment, bubbles and coating cracking. Further information on defects can be found in the technical library.
The conformal coating materials that are more likely to work at such thickness are Humiseal 2A64, a two part polyurethane or Humiseal 1C49 and 1C51, moisture & thermal cure silicone conformal coatings. Further information can be found under Humiseal conformal coatings.