Flammability Rating
The following statement defines Optical Filters position with regards to flammability rating of its laminated products.
No flammability tests have been carried out by Optical Filters on any of the large variety of plastic and glass laminates produced by the Company. The following guide-lines are issued to assist Customers in assessing the suitability of our laminates for their particular application.
The adhesive used in our dry film optical lamination is based on extruded polyurethane. The lamination is achieved though pressure and temperature. Typical total lamination adhesive thickness is 0.25 - 0.76mm. The softening point and maximum operational temperature of this adhesive system is
75șC. No solvents, cold pour adhesive or self-adhesive substrates are involved.
The outer material layers of the laminates are either glass, polycarbonate or, acrylic. The following guidelines may be of assistance;
1.
Glass - Being incombustible it has an excellent flammability rating.
2. Polycarbonate - All polycarbonates used in laminates manufactured from February 2002 have a UL94 HB classification. Registration File No. E165805.
3. Acrylic - Very poor and not suitable for applications requiring a flammability rating. |
The UL94-Vx is a Vertical Burn test in which the sample is ignited from the bottom. The highest rating V0 is obtained when there is no dripping from the sample. V1 allows dripping but no burning droplets. Class V2 allows burning droplets but the fire has to stop before all the material is gone (auto-extinguishing).
If all the material has burnt away in the Vertical Burn test, a similar Horizontal Burn test is performed. The HB rating is issued if material auto-extinguishes. If not, the material is 'not classified'.
In October 1997, all polycarbonate extrusion grades were reclassified by Underwriters Laboratories as UL94-HB. Since then, certain polycarbonate extrusion grades have been retested. Current and valid V-ratings are those which have a date after October 1997 at the top of the UL file yellow
card.
Where a flammability rating is available on a component in the laminate we do not claim or infer that this rating can be extended to the complete laminate. In an application where flammability is an issue, we recommend either a glass or polycarbonate laminate.
Disclaimer: Under no circumstances, including notes on customer drawings, discussion with our staff or extrapolation from substrate supplier's data, does Optical Filters claim any flammability certification or registration from Underwriters Laboratories or other certification body for the flammability of its laminated products.
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