Florida Finishing 2.8 VOC Chromate Epoxy Polyamide Primer Specification
E90-G203 is a two component 2.8 lb./gal VOC compliant, epoxy polyamide Primer.
Type I Yellow ... E90G203 / Catalyst (Component B) ... V93V230
Aluminum: Clean with acidic cleaner or other appropriate cleaner depending on contamination. Pretreat with chromate conversion coating MIL-DTL-5541, wash primer DOD-P-15328, E90G4, or anodize per MIL-A-8625.
Testing: Due to the wide variety of substrates, surface preparation methods, application methods, and environments, the customer should test the complete system for adhesion, compatibility and performance prior to full scale application.
• This product must be properly mixed(catalyzed) before using. ( See mixing instruction for details.)
• Surface preparation is important for performance.
• For good adhesion, parts primed need to air dry a minimum of 2 hours before top coating. If parts have been primed for longer than three days, they must be sanded or re coated with a mist coat before top coating for good adhesion.
• These primers contain strontium chromate. Performance Properties: Meets all the performance properties of MIL-PRF-23377K, Type I, Class C2.
The gloss meter provides a quantifiable way of measuring gloss intensity ensuring consistency of measurement by defining the precise illumination and viewing conditions. The configuration of both illumination source and observation reception angles allows measurement over a small range of the overall reflection angle. The measurement results of a gloss meter are related to the amount of reflected light from a black glass standard with a defined refractive index. The ratio of reflected to incident light for the specimen, compared to the ratio for the gloss standard, is recorded as gloss units (GU).
Measurement angle refers to the angle between the incident and reflected light. Three measurement angles (20°, 60°, and 85°) are specified to cover the majority of industrial coatings applications. The angle is selected based on the anticipated gloss range, as shown in the following table.
Medium Gloss: 10 - 70 GU
Viscosity: (Catalyzed Only)
Note: Viscosity measurements include Base and Catalyst ONLY.
The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal notion of "thickness". For example, honey has a higher viscosity than water.
Viscosity is due to friction between neighboring parcels of the fluid that are moving at different velocities. When fluid is forced through a tube, the fluid generally moves faster near the axis and very slowly near the walls, therefore some stress (such as a pressure difference between the two ends of the tube) is needed to overcome the friction between layers and keep the fluid moving. For the same velocity pattern, the stress required is proportional to the fluid's viscosity. A liquid's viscosity depends on the size and shape of its particles and the attractions between the particles.
A fluid that has no resistance to shear stress is known as an ideal fluid or inviscid fluid. Zero viscosity is observed only at very low temperatures, in superfluids. Otherwise all fluids have positive viscosity. If the viscosity is very high, for instance in pitch, the fluid will appear to be a solid in the short term. A liquid whose viscosity is less than that of water is sometimes known as a mobile liquid, while a substance with a viscosity substantially greater than water is called a viscous liquid.
In paint industries, viscosity is commonly measured with a Zahn cup, in which the efflux time is determined and given to customers. The efflux time can also be converted to kinematic viscosities (centistoke, cSt) through the conversion equations. A Ford viscosity cup measures the rate of flow of a liquid. This, under ideal conditions, is proportional to the kinematic viscosity.
Theoretical Coverage: (no application loss)
Also known as the "Spreading Rate". Theoretical Coverage uses the total contents of an AD-MIXED coating. (Part A, plus Part B, plus Part C) Including all catalyst and reducer necessary to meet the Manufacturer Mixing Recommendations as specified on the Product Data Sheet.
802-1203 Sq Ft/gal @ 0.6-0.9 mils DFT
Per AD-MIXED KIT. Base and Catalyst and Reducer.
Recommended Dry Film Thickness: (DFT)
Coating material when dry (after curing) should typically have a thickness of 30–130 µm (0.0012–0.0051 in) when using acrylic resin, epoxy resin, or urethane resin. For silicone resin, the coating thickness recommended by the IPC standards is 50–210 µm (0.0020–0.0083 in).
There are several methods for measurement of conformal coating thickness and they fall into two categories. These categories are wet film and dry film conformal coating measurements
An alternative method to wet film measurement is using a non contact technique using eddy currents. The system works by placing the test head on the surface of the conformal coating, the measurement is almost instantaneous and provides an immediate repeatable result for thickness measurement of conformal coating.
Test coupons are the ideal method for measuring the coating thickness, whether is it spraying or dipping, and can be kept as a physical record of the performance. Apply the coating to the test coupons at the same time as the circuit boards provides a permanent measurement and an accurate guide to the coating thickness.
MILS Dry: 0.6 - 0.9
Drying Time measurements are based on a 0.8 MIL DFT coating with an ambient temperature of 77°F, and a Relative Humidity of 50%. Note: Top Coat MUST be applied with-in 24 hours of Primer application.
Air Quality Data:
Non-photochemically reactive Volatile Organic Compounds (VOC) Part A as packaged, maximum 2.85 lb./gal, 342 g/L V93V230 as packaged, maximum 2.63 lb./gal, 316 g/L catalyzed as above, maximum 2.8 lb./gal, 340g/L
Tack, Dry Hard, Re-Coat, Force.
To Tack Free: 5 Hours
To Dry Hard: 8 Hours
To Top Coat: 2 Hours
To Force Dry: 45-60 Minutes at 140°F
Use ONLY MIL-T-81772B, Type II Thinner, R91K210.
Always use clean mixing containers.
3 parts E90G203
1 part V93V230
MIL-T-81772B, Type II Thinner, R91K210.
All two-part coatings have a "pot-life" or "working time" during which the coating can be used. Usually the pot-life is a matter of a few hours but is also highly temperature dependent. Both water-borne and solvent based coatings have a Pot-Life.
Based on Environmental Conditions of an ambient temperature of 77°F, and a Relative Humidity of 45%. Higher temperature will shorten pot life.
The total period of time beginning with the date of manufacture, or date of pack, and terminated by the date by which an item must be used (expiration date) or subjected to inspection, test, or disposal action.
Shelf-life is not to be confused with service-life (defined as, A general term used to quantify the average or standard life expectancy of an item while in use.)
From MFG. Date. Based on Unopened container.
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