Problem with colored lenses

[sevalav]

Hello,
My problem started when pair of customers claimed that their grey lenses and G-15 lenses (both were CR-39 n= 1,5, colored lenses with some dioptric power) have red color too. I tried to order a new pair of lenses from the same factory, but they can not coloring lenses without this red color. Also the same thing happened to another two factories. In the end, I bought No Red Gray (#C250-11) color ("Opti-Safe"), and tried to do it myself, but with no good result. The red color was there.
To detect the presence of red color, I am using very simple test. I put one lens over the other (in order to enhance the effect of color) and looked through both lenses so placed in an artificial light source with a hot filament. It must be artificial source of light with a hot filament (incandescent lamp) because this source of light emits the whole spectrum of light. If your light source is white neon light, you will not be able to notice the presence of red color.
I tested the lenses in sunglasses that I have for sale in my optics shops but they do not show the presence of red.
Finally, my question is: what is causing this problem and does anyone know how to avoid the presence of red color in colored lenses?

[harry a saake]

Hello,
My problem started when pair of customers claimed that their grey lenses and G-15 lenses (both were CR-39 n= 1,5, colored lenses with some dioptric power) have red color too. I tried to order a new pair of lenses from the same factory, but they can not coloring lenses without this red color. Also the same thing happened to another two factories. In the end, I bought No Red Gray (#C250-11) color ("Opti-Safe"), and tried to do it myself, but with no good result. The red color was there.
To detect the presence of red color, I am using very simple test. I put one lens over the other (in order to enhance the effect of color) and looked through both lenses so placed in an artificial light source with a hot filament. It must be artificial source of light with a hot filament (incandescent lamp) because this source of light emits the whole spectrum of light. If your light source is white neon light, you will not be able to notice the presence of red color.
I tested the lenses in sunglasses that I have for sale in my optics shops but they do not show the presence of red.
Finally, my question is: what is causing this problem and does anyone know how to avoid the presence of red color in colored lenses?

for the most part you cannot, as red is the base color of all dyes, and it penetrates deeper then the rest, and eventually you get the result you described

[Robert Martellaro]

I seem to remember something about the dyes changing to a more environmentally friendly formula about 15 years ago, making it nearly impossible to dye a lens to a neutral grey. I also remember that dipping the lens in yellow might help to some degree. However, the best solution is to use polarized lenses and avoid dyed lenses completely.

[Chris Ryser]

I seem to remember something about the dyes changing to a more environmentally friendly formula about 15 years ago, making it nearly impossible to dye a lens to a neutral grey. I also remember that dipping the lens in yellow might help to some degree. However, the best solution is to use polarized lenses and avoid dyed lenses completely.

Wrong and based on wrong information ........................................

How come that optical specialists like my friends here on OptiBoard are all up to date on progressive lens technologies and the greatest new type bevel edgers, but have no idea that on the consumables lab side new inventions and new working methods have been made and introduced over the years.

I have developed, made and sold neutral grey and black dyes for about 18 years.

It has been the easiest and cheapest way to make grey and black dyes with a base of red which is the most dominant color and will become more dominant as the blue in the mix starts fading or is used up in the dye bath. Reddish greys and black dyes were made as of the start of tinting optical lenses in the early 1970's and were never changed. It will can take a lot of time to make umpteen times of new dye batches and test and measure them on a spectroscope, in order to produce neutral non reddish greys and blacks. Therefore most dye manufacturers are still using the basic reddish formula from back in the 1970s. Even the Essilor owned lab chain still uses tinting instructions based on it.

Any red in grey/black will become even more dominant on poly and high index materials and adjusted dyes for these materials should be used. The best to tint material is still UN-coated CR39 which means you could provide the best tints on the least expensive lenses.

If you want to tint natural greys without the red shine that gets purple with age, you can do it with my dyes which are in stock at AmconLabs, one of my distributors.



check it ------------------> http://optochemicals.com/tinting_colorguide.htm

[SharonB]

I found that blue and green are the most fugitive colors when it comes to dyes. Dark brown and neutral gray have those components in the dye, along with red. Red seems to last the longest. When the lenses are exposed to sunlight for a long time, brown and gray will take on a purple or red hue due to the long lasting red, and the fading of the other pigments. Incandescent lighting may initially make the tints seem redder right from the get-go. I used to take patients out to the office entrance during dispensing so they could see the tints under natural light... and they would be true to color. I also explained that they would not be using the tints under incandescent lighting anyway. BPI makes a product called "red out" which helps with this, but I found that tinting my gray lenses green first, and then gray, would eliminate the problem. I did the same with dark brown. For many high-index lenses, I tinted them green first too (some would turn blue instead of gray when I used gray dye alone, and some would turn red-purple if I used brown dye alone). I have not tried Chris' product, but if it eliminates the additional dye steps, well then I'm all for it!

[MikeAurelius]

The ONLY TRUE G-15 color can be found in glass lenses. Anything else is a bad copy and should not be sold as being "G-15".

[Jason H]

It is rare these days to have the problem of red tones in grey dyed sunglasses, but not unheard of. Chris, if you truly have the solution i want to hear it - both for my own curiosity and for a particular case I am dealing with now. Please message me - I am interested. Barring that, I side with Robert in favor of polarized. Done and done. Chris, I'm open - change my mind.......please.

[mdeimler]

Yea...just sell polarized. That is, unless there is some unique situation, like a pilot.

[CCGREEN]

The ONLY TRUE G-15 color can be found in glass lenses. Anything else is a bad copy and should not be sold as being "G-15".

Agreed 100%! Anyone been in the business any length of time knows this and I would hope that they did some research to understand the original intent of G-15 what company came up with it and for what purpose.
Anything other then that is like a Gucci knock off from some asian country.

[CCGREEN]

[QUOTE=Chris Ryser;456063]Wrong and based on wrong information ........................................

How come that optical specialists like my friends here on OptiBoard are all up to date on progressive lens technologies and the greatest new type bevel edgers, but have no idea that on the consumables lab side new inventions and new working methods have been made and introduced over the years.]

Because we have Chris Ryser on here looking out for us in that area of the market sir.
And we thank you very much

[mervinek]

Yea...just sell polarized. That is, unless there is some unique situation, like a pilot.

I agree....polarized polarized polarized (with few exceptions) is the way to go.

[TEdFitz]

Red Out? Is that BPI?

[SharonB]

The ONLY TRUE G-15 color can be found in glass lenses. Anything else is a bad copy and should not be sold as being "G-15".

Amen!!! +1

[Robert Martellaro]

Wrong and based on wrong information ........................................

How come that optical specialists like my friends here on OptiBoard are all up to date on progressive lens technologies and the greatest new type bevel edgers, but have no idea that on the consumables lab side new inventions and new working methods have been made and introduced over the years.

I'll defer to the coating and dye experts, and blame any misinformation on a faulty memory (I'm getting old!), although the lab guru who offered the above explanation has never once BS'd me. Regardless, except for therapeutic effect, I haven't ordered a dyed lens in at least ten years.

[AngeHamm]

When the lenses are exposed to sunlight for a long time, brown and gray will take on a purple or red hue due to the long lasting red, and the fading of the other pigments. Incandescent lighting may initially make the tints seem redder right from the get-go.

Amen.

[Chris Ryser]

for the most part you cannot, as red is the base color of all dyes, and it penetrates deeper then the rest, and eventually you get the result you described

I always asked myself why should it be the red, as in the dye business they call it the workhorse color. Why not one of the other 2 main colors of the three, with which you can make any color under the sun or the rain bow.

As we had not been former employees of the first optical dye maker in Miami, we listened to a few dye chemist's who steered us in the opposite way. We did choose blue as the work horse and main color. Bought the fanciest CECIL spectrometer to able to fully check the results to the nanometer.

Along the way we discovered our MicroTints which dye a CR39 lens in 60 seconds to a dark shade and Poly and High index in 4-8 minutes and we applied for patents which were then granted down the road

To come back to the conventional regular dyes, we soon found out that going the blue way, the red color was only used for small adjustments and did not prevail on blacks, greys and browns. So now I just published one of my trade secrets, but I did not say what other ingredients we use.

Hope this makes sense........................

[sharpstick777]

The ONLY TRUE G-15 color can be found in glass lenses. Anything else is a bad copy and should not be sold as being "G-15".

I love your passion about glass Mike, but I would disagree. I have some older Raybans, the G-15 they once sold is not the same as they do today, more green in the older pair, even though they are both Glass and labelled G-15. I know that in the old days Rayban would color match lens pairs to make sure they had the same color tone. So if Rayban cannot maintain perfect consistency how can anyone else? The only thing G-15 makes a claim for is light transmittance, The term "G" could be gray or green, and any combination in between.

[Speed]

Kbco's polarized was a G-15. Last I heard they had started to include a true gray in their product line because people (opticians, not customers) did not like the "greenish" tint. Looking at the website, they have a lens call grey green. That's probably it. It was exactly as a B&L g-15. You could not tell the color difference side by side.

[sevalav]

First, thanks for all information from you . A few questions for you Chris. Where I can buy yours products in Europe? Have you product for grey color, or I must mix several products to get grey color? If there exist, please tell me exactly name of product for these colors: grey (without red), black (wthout red), and G-15 (without red, if this option exist). Also, do you know some books or useful manual about this area about coloring and related problems?
Thanks in advance

[Chris Ryser]

First, thanks for all information from you . A few questions for you Chris. Where I can buy yours products in Europe? Have you product for grey color, or I must mix several products to get grey color? If there exist, please tell me exactly name of product for these colors: grey (without red), black (wthout red), and G-15 (without red, if this option exist). Also, do you know some books or useful manual about this area about coloring and related problems?
Thanks in advance

sevalav....................what you are asking is all on my website which contains over 350 pages of solutions and answers to your questions.
Just scroll down the main page and you will find dozens of links to these subjects. The link to my websites is below my signature of this post.

Tinting lenses is still one of the most profitable parts of an optical lab, either wholesale or retail and we see that all the ones who do not understand this, are promoting pre-tinted sunglasses and polarized ones at much higher prices. You also can give a much better service to your
customers.

[MikeAurelius]

I love your passion about glass Mike, but I would disagree. I have some older Raybans, the G-15 they once sold is not the same as they do today, more green in the older pair, even though they are both Glass and labelled G-15. I know that in the old days Rayban would color match lens pairs to make sure they had the same color tone. So if Rayban cannot maintain perfect consistency how can anyone else? The only thing G-15 makes a claim for is light transmittance, The term "G" could be gray or green, and any combination in between.

When Bausch & Lomb shut down their glass manufacturing facility in Southbridge MA, they sold the formula to Schott in Duryea PA. Because of EPA requirements and a change in the way glass was formulated in the 1970's, Schott *DID* change the formula somewhat, however, the spectral transmission was not changed except in the deep blue portion of the spectrum. This change did result in a slight visible difference, however the bulk of the visible light transmission did not change. Additionally, terms of the sale of the formula were such that Schott could only sell the G-15 and G-30 colors to B & L. This exclusivity lasted until about 1990 or so.

[MikeAurelius]

Unfortunately, G-15 has become a "common" term, however, the "true" G-15 was and still is a glass product. Since Schott sold their ophthalmic glass production to the Italians, I'm not sure if G-15/G-30 will ever be made again, it will depend on demand, mostly foreign demand in Europe and the "far" East.

[Chris Ryser]

Whatever happened with the glass G15 is history, today it is a dye that tints uncoated CR39 the same original color, or at least it should, while many do not.

[uncut]

I love your passion about glass Mike, but I would disagree. I have some older Raybans, the G-15 they once sold is not the same as they do today, more green in the older pair, even though they are both Glass and labelled G-15. I know that in the old days Rayban would color match lens pairs to make sure they had the same color tone. So if Rayban cannot maintain perfect consistency how can anyone else? The only thing G-15 makes a claim for is light transmittance, The term "G" could be gray or green, and any combination in between.

I believe that the lighter G-15 (measurable) is attributed to a change from heat tempering minimum thickness to chem-temp minimum thickness. This is only my observation and conclusion.

[MikeAurelius]

Whatever happened with the glass G15 is history, today it is a dye that tints uncoated CR39 the same original color, or at least it should, while many do not.

Those who ignore or write off the past are usually guilty of re-writing it to suit there own needs. That's been my observations over the years.

It isn't about the COLOR, its about the actual spectral transmission, and no dye could ever match that.