FAQ
ACOMON is a company that has been supplying the Optical Industry with high quality optical monomers for more than 30 years. The company started with Great Lakes Chemical Corporation or GLCC, who acquired the Optical Monomers businesses from Enichem and Akzo Nobel. For more information, please see: About Acomon, page History.
You can use RAV 7AT, RAV 700 or RAV 705 for making lenses below -4.00 power. You can use RAV 7NG or RAV 7AT blended with RAV 7NG to make lenses above - 4.00 power.
For thin & light lenses, we recommend RAVolution®. This monomer is ideally suited for making lenses for rimless application and polarized.
For making tough and scratch resistant mid index lenses, we recommend RAV 755.
By using RAV 7® monomers, you are able to lower costs in production by increasing yields for the whole range of lenses, good tintability, low warehouse yellowing and increased mould life, even with casting sophisticated lenses.
You can use RAV 7NG to make flat top lenses in high yield.
RAV 700, RAV 705, RAV 7AT and RAV 7NG are all very well suited for making sunlenses by a dip dyeing process. If you need to make large numbers of sunlenses with a very consistent colour shade, we advise to use RAV 7MC with in-mass dyes.
Warehouse yellowing is frequently seen with lenses made from ADC monomer when lenses are kept in a lens envelope for more than 6 months. It results in loss of lenses and value, as these lenses need to be discarded late in the value chain.
ACOMON has specially developed the products RAV 7AT and RAV 7NG to prevent warehouse yellowing of lenses, saving you costs and complaints down the line.
If you are suffering from high adhesion during demoulding, resulting in occasional pull-outs, we suggest you to use RAV 713 (for open/shut) or the addition of some RAV 710 (for mould washing). You can also use the pure products RAV 7AT or RAV 7NG. You will see an optimized adhesion, resulting in longer mould life cycles.
You can try RAV 7AT (pure) for low power plus lenses or RAV7NG (pure) or blended with RAV7AT for high power plus lenses. The lower shrinkage during polymerization, combined with a lower exotherm seen with RAV 7NG, increases the casting yields.
This phenomenon is caused by the high shrinkage of the monomer, combined by the type of lens (high minus). Reduction of shrinkage during cure helps. You can use pure RAV 7NG or RAV 7NG blended with RAV 7AT to solve the problem.
At the lens casting step, use the following grades:
- RAV 7NG as a low shrinkage monomer with reduced initiator content. Suitable to cast complex lenses
- RAV 7LC (Low Colour) likely to be used with a low content of a cheap and stable initiator BPO
- RAV 7MC for mass tinting of sunlenses with a one step process with a cheap and stable initiator, cheap soluble dyes, providing a very good colour consistency in the resulting lenses
- RAV 710/RAV 713/RAV 720 to prevent formation of ferns and white arches in high pPlus lenses (so called tinting failures)
At the distributors (warehousing):
- RAV 7AT for 1.50 lenses having best aging stability
Consider the following ACOMON grades:
- RAV 755 for thin and aesthetical lenses with the best mid-index monomer
- RAVolution® as the most affordable material for rimless lenses with an high impact resistance and the best compromise of optical and mechanical properties (thin & light)
If IPP is not available to you, ACOMON offers two alternative options for producing ADC lenses:
- With RAV 7LC you can produce ADC lenses using BPO (benzoyl peroxide) as initiator. BPO is available on all local markets worldwide. Advantage of the use of BPO is the higher safety (ambient temperature stable initiator) and no need for a refrigerated storage
- With RAV 7MC you can produce ADC lenses using a perketal initiator (1,1-bis(t-butylperoxy)-3,3,5,-trimethylcyclohexane). Normally RAV 7MC is used for batch tinting of sunlenses, but blank lenses can also be produced.
