Results 1 to 19 of 19

Thread: Do inexpensive sunglasses have "spray on" uv?

  1. #1
    Optician Extraordinaire
    Join Date
    Jun 2005
    Location
    Somewhere warm
    Occupation
    Dispensing Optician
    Posts
    3,130

    Do inexpensive sunglasses have "spray on" uv?

    I know this is a very strange question, but I had a sunglass rep tell everyone in my office this. No one questioned it, but I am very skeptical. She told us that inexpensive sunglasses (she said under $40.00 retail) often have a spray on UV filter that washes away in 5 or so washes. She says the US has the weakest laws in the world concerning UV in sunglasses.

    This seems competely off the wall to me. I didn't want to say anything at the time....but is there any truth to this? Where did she get this from?

  2. #2
    Doh! braheem24's Avatar
    Join Date
    Feb 2001
    Location
    KOCF & 89ft ASL
    Occupation
    Other Eyecare-Related Field
    Posts
    3,843
    plastic lenses block over 85% of UV transmission without a UV filter.

  3. #3
    Optical Chemical Manufacturer
    Join Date
    Jan 2006
    Location
    at Home
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    342

    UV coating Manufacturer

    We manufacturer various UV coatings used by labs and lens manufacturers. I suppose it is possible. But, a proper UV coating is generally applied in a bath process and is just not that expensive per pair when done in a production environment. A bath process is easier and cheaper to do than a spray-on due to issues of viscosity and an even distribution with out pooling on the lens surface. In addition the bath process would offer less waste and a higher performance coating when done properly.

  4. #4
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240

    Redhot Jumper

    Quote Originally Posted by braheem24 View Post
    plastic lenses block over 85% of UV transmission without a UV filter.
    CR39 lenses would yellow in no time in the 1970''s, so lens manufacturers would put a clear UV absorber into the monomer before casting the lens. This would then absorb UV up to 360 nm, and lenses would not get yellow anymore. (This would cover UV B which is the range fro 270 to 360 nm that will give sunburns at NM)

    In the early 1950's it was proven that that the long range UV A from 360 to 400nm would initiate long term damage to the eye as cataract and other problems.

    Therefor CR39 will protect for sunburns, but not for longterm problems which pop up years after having no protection. Polycarbonate lenses will protect up to 400nm.

    Any treated CR39 that protect up to the full 400nm, as it should, has a yellowish tinge. Any treated lens that is clear will protect only half way between the 360nm and the full 400nm.

    Any optician selling clear looking UV absorbing CR39 lenses is protecting the patients eyes only half way to the 400 mark. :finger:

    Many opticians have chosen to sell clear UV lenses , because they look better without caring about the protection the patient gets, while forgetting that they could tint over the yellowish tinge at 400nm so it looks nice,
    Last edited by Chris Ryser; 03-23-2007 at 09:02 AM.

  5. #5
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240

    Get a good UV Meter...................

    Any of you guy's and girls should have a proper UV meter that also measures visible transmission in you store or office, so you can check a new job as well as one you have dispensed a while ago, or a job from LC who uses a 1 minute version UV treatment that is proven not to be permanent.

    Last edited by Chris Ryser; 03-23-2007 at 04:20 AM.

  6. #6
    Banned
    Join Date
    Dec 2006
    Location
    On Top
    Occupation
    Other Eyecare-Related Field
    Posts
    1,662
    Quote Originally Posted by braheem24 View Post
    plastic lenses block over 85% of UV transmission without a UV filter.
    . What Chris said.

  7. #7
    Master OptiBoarder OptiBoard Gold Supporter DragonLensmanWV's Avatar
    Join Date
    Oct 2006
    Location
    The Greatest Nation
    Occupation
    Optical Retail
    Posts
    7,645
    Quote Originally Posted by Happylady View Post
    I know this is a very strange question, but I had a sunglass rep tell everyone in my office this. No one questioned it, but I am very skeptical. She told us that inexpensive sunglasses (she said under $40.00 retail) often have a spray on UV filter that washes away in 5 or so washes. She says the US has the weakest laws in the world concerning UV in sunglasses.

    This seems competely off the wall to me. I didn't want to say anything at the time....but is there any truth to this? Where did she get this from?
    That sounds like a rep to not do business with.
    DragonlensmanWV N.A.O.L.
    "There is nothing patriotic about hating your government or pretending you can hate your government but love your country."

  8. #8
    Bad address email on file
    Join Date
    Feb 2005
    Location
    Wisconsin for now
    Occupation
    Dispensing Optician
    Posts
    78
    Hi everybody!, I'm still around.
    Questioning the UV proprties of sunglasses brings many myths.
    First of all, I do not know of many SUNGLASSES that do not meet the required 98% absorption of UV to 400nm- please correct me if wrong.
    The US does require this as minimum protection on all sunglasses- even the cheap stuff: must follow ANSI Z80.5 sunglass standard.
    The suggestion of having some method of measuring UV transmission is best followed, but beware not all such equipment provides accuate measurement to 400nm.
    Denny

  9. #9
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240

    Redhot Jumper Not all meters are the same...................

    Quote Originally Posted by DoubleD View Post
    .......................but beware not all such equipment provides accuate measurement to 400nm.
    Denny
    This is totally correct...............there are several UV meters on the market that are adjusted to read 100% UV absorbtion at 382nm. This is due to their sales of 1 minute and clear UV solutions which do not go higher.
    .....As I said before a proper UV absobtion on a clear lens has to have a yellowish tinge..........and if you dont like the appearance of it tint over with a light brown.

  10. #10
    One of the worst people here
    Join Date
    Jan 2004
    Location
    Canada
    Occupation
    Other Eyecare-Related Field
    Posts
    8,331
    The cheap stuff use cheap acyrlyic that blocks UV

  11. #11
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240

    Redhot Jumper Funny..................

    Quote Originally Posted by Happylady View Post
    ......................She says the US has the weakest laws in the world concerning UV in sunglasses.
    Actually if you wear no sunglasses or clear Rx Glasses outside you get full exposure of at least UV A...................so its not only sunglasses it's all Rx glasses too.

    I could actually go and sue the optician if I would develop a cataract, because when I purchased the glasses he never mentioned or suggested or pushed to have the lenses treated for UV protection.

    On the contrary the optician pushed to sell AR coatings which transmit UV at an even higher rate..

  12. #12
    Banned
    Join Date
    Jun 2000
    Location
    Only City in the World built over a Volcano
    Occupation
    Dispensing Optician
    Posts
    12,996
    Could you sue the prescriber who found no need for correction but did not prescribe plano UV glasses? Of course not. If one did sue anyone for this it would be in court forever (if both sides had money) as there are a good many "experts" who claim cataracts are no higher as percent of the population in areas that have holes in the Ozone and high UV exposure.

    It's a good product but don't claim it's the word of God that you have to have it. I see that practioners that fill thier own Rx's always specify U.V. and those few left that don't do not seem to care. Could it be that our concern is at least partially ecconomicly motivated?

    Chip

  13. #13
    Bad address email on file
    Join Date
    Feb 2005
    Location
    Wisconsin for now
    Occupation
    Dispensing Optician
    Posts
    78
    Chip,
    I agree with you somewhat.
    There is no real proven evidence of cataract formation due directly to UV exposure, but there is leading evidence that it may be likely.
    As far as SUNGLASSES (original post), any dark lens limiting light transmission will also produce dilation, dramatically increasing UV eposure/ effect. I would always assure UV absorption in sunglasses.
    Are we liable, maybe not, but we are not really sure, are we.
    Denny

  14. #14
    Master OptiBoarder OptiBoard Gold Supporter DragonLensmanWV's Avatar
    Join Date
    Oct 2006
    Location
    The Greatest Nation
    Occupation
    Optical Retail
    Posts
    7,645
    Quote Originally Posted by DoubleD View Post
    Chip,
    I agree with you somewhat.
    There is no real proven evidence of cataract formation due directly to UV exposure, but there is leading evidence that it may be likely.
    As far as SUNGLASSES (original post), any dark lens limiting light transmission will also produce dilation, dramatically increasing UV eposure/ effect. I would always assure UV absorption in sunglasses.
    Are we liable, maybe not, but we are not really sure, are we.
    Denny
    I've always wondered about the dilation effect. I see where it could be a problem with wrap frames, but in regular frames is there not enough light leakage around the lens to minimize the effect?
    DragonlensmanWV N.A.O.L.
    "There is nothing patriotic about hating your government or pretending you can hate your government but love your country."

  15. #15
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240

    Thumbs up Lawyers.......................

    Quote Originally Posted by DoubleD View Post
    Are we liable, maybe not, but we are not really sure, are we.
    Denny
    Liable or not...........is'nt the good old USA the heaven for lawyers, ambulance chasers and crazy litigations of all sorts?

    Actually in reference to the word "surface" one of the ultimate surface destruction test's is the so called Florida test. Expose the object to the Florida sun and wait how long it takes until the surface is destroyed by the UV rays emitted by the sun.

  16. #16
    Master OptiBoarder Snitgirl's Avatar
    Join Date
    May 2005
    Location
    North Vancouver, British Columbia, Canada
    Occupation
    Dispensing Optician
    Posts
    1,764
    Quote Originally Posted by DragonLensmanWV View Post
    I've always wondered about the dilation effect. I see where it could be a problem with wrap frames, but in regular frames is there not enough light leakage around the lens to minimize the effect?
    Speaking of the dilation effect, I've noticed parents purchasing the absolute "darkest" sunglass they can find for their toddlers.:finger:

    Was wondering if our fellow Optiboarders can give their opinion on how dark sunglasses should be on a toddler?

  17. #17
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240

    Redhot Jumper Dark.........................

    Quote Originally Posted by Snitgirl View Post
    Was wondering if our fellow Optiboarders can give their opinion on how dark sunglasses should be on a toddler?
    When I learned the practical side of selling in the optical, still in the glass age (which absorbs UV), we were taught to always if possible, sell sunglasses in the 50% absorbtion range because of the dilation effect with darker sunglasses.

    The darker they are the more the pupil opens and if you don't have the full UV protection you'll catch the rays with the included damage effect.

  18. #18
    Banned
    Join Date
    Jun 2000
    Location
    Only City in the World built over a Volcano
    Occupation
    Dispensing Optician
    Posts
    12,996
    Denny:
    The point was that as an absolute has not been defined all the courts could do is listen to a lot of theory and BS and since there is an infinite supply for both sides with no definitive answer the issue could not be decided. Something like man's effect on Global Warning. Al Gore's people are absoutely convinced one way, some people are in doubt and some people are absolutely convinced that man has no or negligable effect.

    Why look for trouble where it doesn't exist?

    Chip

  19. #19
    Optician Extraordinaire
    Join Date
    Jun 2005
    Location
    Somewhere warm
    Occupation
    Dispensing Optician
    Posts
    3,130
    The sunglasses the rep was talking about are the kind you find in Wallmart and places like that, not prescription ones.

    So no one else has ever heard this? I wonder where she got it from.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Dispensing via "drop-shipping" vs. "from the board"
    By ilanh in forum General Optics and Eyecare Discussion Forum
    Replies: 15
    Last Post: 12-07-2007, 11:14 AM
  2. Replies: 0
    Last Post: 10-24-2006, 01:12 PM
  3. I need "Sport Sunglasses" help
    By hip chic in forum General Optics and Eyecare Discussion Forum
    Replies: 11
    Last Post: 07-26-2003, 11:09 PM
  4. Define the terms "Optician" and "Opticianry"
    By Pete Hanlin in forum General Optics and Eyecare Discussion Forum
    Replies: 12
    Last Post: 03-27-2001, 11:26 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •