My last couple of glasses from them, however, gives me reason for
concern. After about a year, the coating starts PEELING off. It starts
right at the very edge. When it starts, you can see a very tiny row of
"ripples" right on the edge of the lens - we're talking very tiny, less
than .5mm wide - running for about an inch or so along the edge of the
surface.
Over time, it spreads around the circumference of the lens, and you can
see a line gradually moving inwards, where the coating is literally
peeling or flaking off. It's pretty hard to see, you have to hold it up
to the light and look real close. My current glasses are a year and a
half old, and the line has moved inward about 1/8" from about half the
circumference.
Note: these are NOT scratches. It is peeling or flaking. My last pair
did this, and after a couple of years, about half the surface of the
lens was peeled off. I bought a new pair about a year ago, and now THEY
are doing it, and I have been super-careful to clean them with a lens
cleaner and soft cloth, only occasionally using a tissue.
The new manager at the LC where I bought them is an idiot: long, greasy
hair over his shoulders, dirty tennis shoes, baggy pants... where do
they HIRE these people????!!! He just said well, if you clean them with
water and a soft tissue or cloth, "that coating'll come right offa
there." He wouldn't discuss it further.
These are Featherwates, WITHOUT the AR coating, which is too soft. I
always tell them I want maximum scratch-resistance, which includes some
kind of anti-scratch coating. I need the Featherwates because my
prescription is pretty thick: -5.75/-5.50 w/astigmatism.
Now my wife needs to replace hers. She bought hers at LC *8* years ago,
and has abused them horribly. She does medical work, and constantly
wipes them with her scrubs or lab coat, yet they STILL look like she
bought them yesterday! Not a scratch on them! Given my experiences the
last 3 or 4 years, I'm worried that now she's going to have the same
problem I've had.
Her prescription is unremarkable: OD -2.0 sphere, OS -1.5 -.5
cylinder, add +1.5.
Can anybody give us a tip here? For reasons I won't go into, we'd like
to stay with LC, but this "peeling coating" problem really bothers me.
What the heck is going on?
Thanks,
Ron M.
email:
ronN...@peacefulhills.net
("reply to:" above won't work)
> Can anybody give us a tip here? For reasons I won't go into, we'd like
> to stay with LC, but this "peeling coating" problem really bothers me.
> What the heck is going on?
>
Vote with your feet. You have a customer service issue, which is that your
lenses didn't last their expected lifetime, and you weren't offered any
satisfaction. Why would you go to a provider you're unhappy with?
--
Scott
Reverse name to reply
The only way to get truly durable coatings is to use real glass lenses and
deposit the coating by evaporation with the lenses heated to high
temperature.
I do mean durable. Good coatings deposited that way just will not come off
unless you really work at it. Poor technique, of course, can change a good
process into garbage. By hot, I also mean very hot, 250°C minimum for single
layers of magnesium fluoride on glass. It is very difficult to find a place
that will do that these days. If you find one, let me know.
There are coating laboratories charging high prices that will make hard
coatings but it is not economically feasible for spectacle lenses.
Bill
-- Fermez le Bush
> The only way to get truly durable coatings is to use real glass lenses
> and deposit the coating by evaporation with the lenses heated to high
> temperature.
>
That said, put a number on the expected lifetime of a lens. As a consumer,
my number is two years. If a coating fails before that time through no
fault of my own before two years, I would expect the optical shop to do
more than say "that's life".
I don't know where you have been living, but the newer A/R coatings
like Crizal are incredibly durable, and come with a minimum of a two
year warranty. It all had to do with finding the right coating for the
particular polymer substrate.
DrG
>We've bought glasses from Lenscrafters for over 25 years now, and
>they've always been very sharp and durable, lasting 4-8 years before
>replacement, and even then, we just replace them because the
>prescription changed.
>
>My last couple of glasses from them, however, gives me reason for
>concern. After about a year, the coating starts PEELING off. It starts
>right at the very edge. When it starts, you can see a very tiny row of
>"ripples" right on the edge of the lens - we're talking very tiny, less
>than .5mm wide - running for about an inch or so along the edge of the
>surface.
>
>Over time, it spreads around the circumference of the lens, and you can
>see a line gradually moving inwards, where the coating is literally
>peeling or flaking off. It's pretty hard to see, you have to hold it up
>to the light and look real close. My current glasses are a year and a
>half old, and the line has moved inward about 1/8" from about half the
>circumference.
>
>Note: these are NOT scratches. It is peeling or flaking. My last pair
>did this, and after a couple of years, about half the surface
Front or back surface? If it's the front it's potentially a defect in the lens
blank- that's the lens manufacturers coating. If it's the back surface, the
coating is applied by Lenscrafters, assuming the lenses were not finished blanks
(Rx pre-ground off the shelve).
>of the
>lens was peeled off. I bought a new pair about a year ago, and now THEY
>are doing it, and I have been super-careful to clean them with a lens
>cleaner and soft cloth, only occasionally using a tissue.
>
>The new manager at the LC where I bought them is an idiot: long, greasy
>hair over his shoulders, dirty tennis shoes, baggy pants... where do
>they HIRE these people????!!! He just said well, if you clean them with
>water and a soft tissue or cloth, "that coating'll come right offa
>there." He wouldn't discuss it further.
They should be cleaned with water, and soap. A clean cloth without fabric
softener or tissues without or with very little lotion is ok too.
>These are Featherwates, WITHOUT the AR coating, which is too soft. I
>always tell them I want maximum scratch-resistance,
That would be glass- try and get that at Lenscrafters!
>which includes some
>kind of anti-scratch coating. I need the Featherwates because my
>prescription is pretty thick: -5.75/-5.50 w/astigmatism.
Try Hoya's 1.70 index lenses. Thinner than poly (not lighter in weight though)
with better optics, and is also unavailable a LC.
Lenscrafters pushes poly because they own Gentex, one of the two poly
manufacturers.
>Now my wife needs to replace hers. She bought hers at LC *8* years ago,
>and has abused them horribly. She does medical work, and constantly
>wipes them with her scrubs or lab coat, yet they STILL look like she
>bought them yesterday! Not a scratch on them!
Hold them up to a light source. You'll find plenty of scratches.
>Given my experiences the
>last 3 or 4 years, I'm worried that now she's going to have the same
>problem I've had.
Maybe. Are her lenses cr39 or poly?
>Her prescription is unremarkable: OD -2.0 sphere, OS -1.5 -.5
>cylinder, add +1.5.
>
>Can anybody give us a tip here? For reasons I won't go into, we'd like
>to stay with LC, but this "peeling coating" problem really bothers me.
>What the heck is going on?
Some of the problem may be environmental, poly is extremely sensitive to
chemicals.
>Thanks,
>Ron M.
>
>email:
>ronN...@peacefulhills.net
>("reply to:" above won't work)
Robert Martellaro
~~~~~~~~~~~~~~~~~~
Optician/Owner
Roberts Optical
Wauwatosa, Wi.
~~~~~~~~~~~~~~~~~~
"Science is a way of trying not to fool yourself."
- Richard Feynman
The "peeling" I've described is on the front, and starts about 12
months after buying them.
One person said poly is sensitive to chemicals. Would this include
chemicals like the standard blue Windex glass cleaner? I've used that a
number of times to clean them; could that be a factor? What about
dishwashing liquid?
Thanks again,
Ron M.
>Thanks for all the comments, not that they really change anything.
>Obviously, LC has changed its processes. My whole family has bought
>glasses there, always the Featherwates Plus, and until the last 3 or 4
>years, they've lasted as long as 8 years. Sure, they might get
>virtually invisible scratches on them from normal wear after a few
>years, but in general they stay looking perfectly new.
>
>The "peeling" I've described is on the front, and starts about 12
>months after buying them.
Ok, I've seen this with Vision Ease lenses, mostly from two to five years ago. I
don't know if it's a flaw in the product or if the labs are processing them
incorrectly. For me, it was one more nail in the coffin for poly. Ask for
Trivex, and no surprise, that's not available at LC also.
>One person said poly is sensitive to chemicals. Would this include
>chemicals like the standard blue Windex glass cleaner? I've used that a
>number of times to clean them; could that be a factor? What about
>dishwashing liquid?
Hot water and soap. Dish liquid, Ivory, most any soap that is free of lotion and
abrasives. Do not use household cleansers on the frame or lens.
>Thanks again,
>Ron M.
Your welcome.
I once got a Crizal coating. I was surprised that it lasted two years. But
after two years, it deteriorated rapidly.
Have you had any experience with modern hot coatings such as used on high
quality camera lenses or laser rods? Typical materials used are magnesium
fluoride, silica, titanium dioxide (not always very durable), silicon
monoxide, thorium fluoride and various other metal oxides. These are tested
with rubber erasers and Scotch tape. Will Crizal pass such tests?
With the trend toward plastic lenses, hot coatings are not feasible.
>
> Have you had any experience with modern hot coatings such as used on high
> quality camera lenses or laser rods? Typical materials used are magnesium
> fluoride, silica, titanium dioxide (not always very durable), silicon
> monoxide, thorium fluoride and various other metal oxides. These are tested
> with rubber erasers and Scotch tape. Will Crizal pass such tests?
Without a doubt. I clean my glasses with paper towels just to convince
myself. The coating is still intact.
DrG
[snip]
>Lenscrafters pushes poly because they own Gentex, one of the two poly
>manufacturers.
Does GENTEX still manufacture/sell their "Profile" aspheric poly
lenses? I remember they sent out something like a +4.00 blank in a CD
case just to show how thin it was. I just haven't seen our local lab
use them in ages (if I order aspheric poly, I usually let the lab
choose and they've been using Tegra's lately).
>One person said poly is sensitive to chemicals. Would this include
>chemicals like the standard blue Windex glass cleaner? I've used that a
>number of times to clean them; could that be a factor? What about
>dishwashing liquid?
Poly is mildly sensitive to (91% isopropyl) alcohol and quite
sensitive to acetone.
I've had no problems using glass cleaner on poly.
> Hot water and soap. Dish liquid, Ivory, most any soap that is free of lotion and
> abrasives. Do not use household cleansers on the frame or lens.
It looks like this may have been the culprit. In all 3 of the glasses
this "peeling" has happened with, I have frequently cleaned them using
a small bottle of Windex I keep in my office. A guy at LC said to avoid
any chemicals containing alcohol or ammonia; they will definitely get
the coating started coming loose, starting at the edges as mine did.
Dishwashing soap MIGHT be OK, but it's hard to say, because so many of
them contain perfumes, antiseptics, and a bunch of other chemicals.
Ron M.
> These are Featherwates, WITHOUT the AR coating, which is too soft. I
> always tell them I want maximum scratch-resistance, which includes some
> kind of anti-scratch coating. I need the Featherwates because my
> prescription is pretty thick: -5.75/-5.50 w/astigmatism.
>
> Her prescription is unremarkable: OD -2.0 sphere, OS -1.5 -.5
> cylinder, add +1.5.
I think it's rather obvious that your wife's coating is factory
applied. Your lenses, because of the prescription, are surfaced, and
the coating is applied in the lab.
DrG
Ron
You evidently misunderstood. "LC" purchases their lens blanks. Stock
lenses can be purchased from the manufacturer with the coating already
applied to both sides. But, in higher prescriptions, the lenses are
ground, or "finished" on the back surface by the lab, with the SC
applied afterwards. Fewer problems generally arise with
factory-applied coatings as opposed to coatings applied by finishing
lab.
Why does your wife use 91%?
The next time around, make sure not to order polycarb, and make sure
that your lenses have a finish such as Alize, Crizal, or Zeiss Carat.
You'll pay more, of course.
DrG
Paper towels should be a snap. Erasers test durability and Scotch tape tests
adherence.
> Paper towels should be a snap. Erasers test durability and Scotch tape tests
> adherence.
Ya, well we generally try to discourage using erasers and scotch tape
on lenses. 3M used to provide a kit with a piece of steel wool to
demonstrate the toughness of their anti-scratch coating. Maybe we need
to revisit that little gimmick.
It's unlikely they'll use Gentex if they're not an "Essilor lab". My lens book
shows that the Profile is available in 14 BCs from +.25 to +8.00.
To be sure, a +4.00D looks better on a 5 base than a 8 base, the use of
asphericity does not improve the vision- it just allows the use of flatter
curves without compromising the off-axis optics.
Regards,
Robert Martellaro
~~~~~~~~~~~~~~~~~~
Optician/Owner
Roberts Optical
Wauwatosa Wi.
~~~~~~~~~~~~~~~~~~
"An expert is a person who has made all the mistakes that can be made in a very narrow field."
- Niels Bohr
With hard hot coatings on glass, discouragement would not be necessary.
> With hard hot coatings on glass, discouragement would not be necessary.
I hate to say this, but I think you might be a bit out of step with the
times. Polymers are much lighter than glass, and are also safer.
DrG
I will admit to be a stick-in-the-mud. I still like old fashioned hardware
stores. Book stores where you can handle weird books. I liked fly fishing
before it was yuppified.
Besides, there still are coating houses that make superbly durable coatings.
They just do not find their way onto ophthalmic lenses.
> I will admit to be a stick-in-the-mud. I still like old fashioned hardware
> stores. Book stores where you can handle weird books. I liked fly fishing
> before it was yuppified.
I can relate. I still don't use a food processor. I remember a great
bookstore in Evanston, Illinois called Great Expectations. There used
to be another good one here in Dallas, called Major's Scientific
Books.....Ah, well.
> Besides, there still are coating houses that make superbly durable coatings.
> They just do not find their way onto ophthalmic lenses.
No doubt, but the cost for ophthalmic goods would probably be too high.
Judging from the tone of this NG, most people want cheaper, not
better.
DrG
> No doubt, but the cost for ophthalmic goods would probably be too high.
> Judging from the tone of this NG, most people want cheaper, not
> better.
>
My bad. I should have said cheaper AND better, but sometimes the two
are mutually exclusive.
DrG
>> Besides, there still are coating houses that make superbly durable coatings.
>> They just do not find their way onto ophthalmic lenses.
>
> No doubt, but the cost for ophthalmic goods would probably be too high.
> Judging from the tone of this NG, most people want cheaper, not
> better.
I am sure that the real problem is that dispensing opticians do not want a
hot vacuum coating station around. In the old days, almost anyone could do
the hot magnesium fluoride coatings. The true key to success was to clean
the glass well. When the coating was the correct thickness, it had a
distinctive bluish purple color so that the need for a thickness monitor was
eliminated. My guess is that conversion to plastic eliminated all hot
coating.
Dennis
Much, much diluted) Dawn soap -- does that have either
alcohol or ammonia in it? (Has no smell, at least no
ammonia-smell). Is what I use for my *glass* lenses.
So, what about Dawn on plastic/whatever?
David