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General Description of UV-cure
Prism Powder Coatings V-series is designed for application of temperature sensitive substrates like medium density fiber board, various metal substrates including castings and to a limited degree over plastics. The V-series of powders can be handled like conventional powder coatings for spray application, but will require special UV-curing lamps for cure. The availability of colours, gloss ranges and textures is limited, but steadily expanding.
Typical uses for UV-cure powders
UV-cure powder is used on office desks (MDF), store displays (MDF), aluminum castings, shelving (MDF / Metal), TV / Stereo stand (MDF / Plastic) pre-assembled parts (MDF / Metal / Plastic) and other temperature and process sensitive parts.
Limitations
Some UV-curable powder coatings are developed for application over MDF and a conductive treatment or preheating of the substrate is required.
Specific formulations exhibit good adhesion to metal, others are specific to MDF-"wood" substrates. Adhesion to plastic is often problematic, as well as the heat-distortion of lower softening plastic material.
Infra-red and UV-light cures only what is "sees" and parts hidden from the UV-light exposure do not cure. The choice of UV-lights like wattage and H-bulb (Hg) or V-bulb (Ga) will influence cure. Not all colour pigments, especially in opaque finishes, can be used for this application. UV-light penetration / cure at opaque finishes with high film thickness (5 mils +) is reduced.
Coating performance
| Over MDF |
| Hardness (pencil): |
H-4H range |
| Adhesion: |
3 – 4B (95-100%) |
| Impact Resistance: |
up to 80 inch/lbs (direct) |
| 60° Gloss: |
40 - 90 and lower gloss available in fine Sandtex finish |
| Stain Resistance: |
generally resistant for short exposures to a wide variety
of household items, but formulation dependant. |
| Outdoor Durability: |
Formula Specific |
| Abrasion: |
50 - 100 MG loss (Taber CS 17 / 1000 cycles, 1000 gram) |
| Over Metal (chemically pretreated) |
| Hardness: |
H-4H range |
| Adhesion: |
Formula Specific |
| Humidity Resistance: |
up to 1000 hrs |
| Salt Spray Resistance: |
up to 500 hrs on B-1000 treated substrate |
| Outdoor Durability: |
generally resistant for short exposures to a wide variety
of household items, but formulation dependant. |
| Outdoor Durability: |
standard and super durable versions available
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Curing Cycles
For MDF (Medium Density Fibre) board and selected plastic:
- Preheat 60 - 100°C (140°F - 210°F) surface temperature (typically via 'IR' + convection)
- Apply powder
- Melt powder 80 - 150°C (175°F - 300°F) surface temperatures (typically via 'IR" + convection)
- Cure UV-lamps (seconds)
- Type "H"-bulb for transparent colours semi/transparent finishes
- Type "V" bulb (or combinations of H&V) for opaque finishes
For metal:
- Apply powder
- Melt powder 80 - 150°C (175°F - 300°F) metal temperature
- Cure UV-Lamps (seconds)
- Type 'H' for transparent finishes
- Type 'V' (or combinations of H&V) for opaque finishes
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| MDF Coating |
MDF Coating |
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| MDF Coating |
MDF Coating |
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