Harder, stronger, clearer.
Presenting new technologies and advancement in spectacle lens materials CET approved C-36183
For Trivex Lens Specialist Practices, UK
A live webinar presented by the ABDO College in Canterbury, UK in association with PPG Optical Materials Course Outline
Kevin Gutsell FBDO (Hons) SLD ABDO • Introduction • Timeline of lens material technology developments • Overview of lens materials technologies • Lens material properties and patient benefits Dora Plisic Trade Manager • Developments in lens design and coating PPG Optical Materials technologies • British consumer trends • Summary and Q&A
Keith Cross (guest speaker) Director, Rx Technologies, R&D PPG Optical Materials
How has technology overall evolved over the last 60 years? Technology Evolution: The Telephone
3G: 1st country to launch - UK
1937 1977 1983 1991 2001 2007
2G: 1st GSM network Technology Evolution: The distribution model
New contract is signed
2 years contract with mobile phone network providers
New mobile phone platform is provided How has technology in the ophthalmic lenses evolved over the last 60 years? Anatomy of an ophthalmic lens
Patient comfort Technology Developments in Lens Materials
1950’s CR-39® lens development begins
1970’s FDA impact test regulation increases use of CR-39® lenses 1980’s Polycarbonate lenses become more popular in U.S.
2000’s Trivex® lenses introduced
Prescription Distribution 85% of Rx’s in Western Countries are in the range of +/-3.00 D Technology Developments in Lens Materials
1980’s Mid Index (1.56, 1.60) lens development begings
1990’s Additional developments in high index lenses (1.60, 1.67)
2000’s Very high index lenses development (1.74)
Prescription Distribution In the Pacific region, prescriptions are higher from +/-3.00 to +/-6.00 D What is a lens material made from? Lens material overview: CR-39®
Chemistry Structure •Organic (Carbon-based) •Thermoset •Properties: •Highly cross-linked • Impact resistance better than glass • High resistance to heat • High Abbe number • Lighter than glass Lens material overview: Polycarbonate
Chemistry: Structure: •Organic (Carbon-based) •Thermoplastic •Properties: •Long independent chains • High Impact resistance •Not cross-linked from 90° angle only • Low resistance to heat • Low Abbe value Lens material overview: High Index
Chemistry: Structure: •Organic (Carbon-based) •Thermoset • Urethane backbone with added sulfur to •Highly cross-linked increase refractive index •1.60: approximately 30% sulphur •1.67: approximately 40% sulphur •1.74: approximately 60% sulphur •Properties: • Thinner lens • Lower optical performance • Higher density Lens material overview: Trivex®
Chemistry: •Organic (Carbon-based) •Urethane backbone enriched with Urea (Nitrogen) •Properties: • High Impact resistance • High Resistance to heat • High Optical performance Structure: • Lightest prescription lens •“Quasi-Thermoset” material •Slightly cross-linked long chain structure How does this translate to the overall performance properties of the lens? Patient comfort Clear Vision: Abbe Number
60 CR-39 (58)
50
Trivex (45)
1.60 40 (40)
1.74 1.67 Polycarbonate (33) (31) 30 (30)
Clearest 17
The Abbe Number (V-value) is a measure of the dispersion exhibited by the material. The higher the Abbe Number the more accurately a lens aligns the spectrum of light waves that pass through it. Lightweight: Density
1.10 Trivex 1.11 g/cm3
Polycarbonate 1.20 1.20 g/cm3
1.60 1.30 CR-39 1.30 g/cm3 1.31 g/cm3
1.67 1.36 g/cm3
1.40
1.74 1.47 g/cm3 1.50
Heaviest Lightest
Density expresses the weight of the material. The lower the density, the lighter and more comfortable the lens will be for the patient. Thin: Refractive Index
1.75 High Index 1.74
1.70
High Index 1.67
1.65
1.60 Mid Index 1.60 Polycarbonate 1.59
1.55
Trivex 1.53
1.50 CR-39 1.50
Refractive index is the ratio of the velocity of light in vacuum to that in the material. It tells us how fast light travels through a material. Eye Health: UV Protection
400 High Index 1.74
Trivex High Index 1.53 1.67
390
Polycarbonate 1.59
380 Mid Index 1.60
CR-39 350 1.50
UV cut- off (nm) Ultra violet (UV) radiation is known to cause skin cancer and protection of the eyes from UVA and UVB is considered essential for every patient. Safety & Protection: Durability
>700 Polycarbonate Trivex >700 in-lbf >700 in-lbf
300
200
100
1.60 1.67 53 in-lb 56 in-lb CR-39 f f
31 in-lbf 0 21
Brittle Resilient How do these features translate into patient benefits? Patient Comfort
•80 percent of what children learn in their first 12 years comes through their eyes
• 64.5% of adults are physically active
• Seniors have aging and thinner skin on their nose
• Rimless frames require durable lens that wont break or crack
• UV levels are three times greater in summer than winter • 20% of cataract cases are due to UV rays • The most of UV damages to eye happen prior to the age of 12 as the eye is not mature and fully protected against UV
Lens is not one feature it is the combination of the features to insure patient comfort Potential benefits to ECPs Lens materials positioning
1.74 High-Index Trivex® tribrid™ HIGH END Europe & US
1.67 High-Index
1.60 High-Index Europe Europe & US MID-RANGE
Polycarbonate US
BASE / ENTRY 1.56 Mid-Index ADC / CR-39® Global Asia
DIOPTRES 0.00 +/-3.0 +/-7.00 Knowledge is power
• Understanding the patient – Understanding patients needs – Understanding patients lifestyle – Understanding patients expectations
• Educating patients about lenses
• Repeating the benefits of recommended lens
• Using regular mailings to keep in touch with the patient. Lens materials - market share UK
HIGH END 0,58%
20,12%
MID-RANGE 3,6%
1,80%
ENTRY 73%
Source: Strategy with Vision, market data for Y2011 Lens design - market share UK
21,32%
11,27%
67,41%
40%
60%
Source: Strategy with Vision, market data for Y2011 Lens coatings - market share UK
HIGH END 18,80%
20,30% MID-END
17,40%
ENTRY 43,40%
Source: Strategy with Vision, market data for Y2011 Have our dispensing trends evolved with the technology? To summarize - market share UK
18,80% HIGH END 40%
0,58% 20,30% MID-END 60%
23,72% 60,80%
ENTRY 11,27% 73%
Source: Strategy with Vision, market data for Y2011 Consumer trends
UK is becoming one of the worlds most web and gadget obsessed countries according to the latest survey results from Ofcom's annual communications market report.
• Britain has become a gadget-obsessed nation, watching more television online, spending more on internet shopping and using smartphones and tablets to access the web more heavily than any of the world's leading economies, according to new research. • The British love of the latest devices has even seen the UK overtake Japan in mobile internet use, according to the report from media regulator Ofcom, which compares data across 17 countries, including the US, China, India, Russia, Brazil, Ireland, Sweden, France and Germany.
• Mark Sweney • The Guardian, Thursday 13 December 2012 • Britons are biggest online shoppers in developed world • Britain is the biggest online shopping nation in the developed world, with almost two-thirds of adults using the internet to buy goods or services. • By James Hall, Consumer Affairs Editor • 2:17PM GMT 01 Feb 2012 PATIENT COMFORT Questions and Answers from live Webinar ABDO College, 30th April 2014
Q: With regards to Tinting Trivex lenses I understand there can be concerns with A/R consistency, pinholes and bubbling. Has this now been resolved in 2014? Does tinting affect impact resistance?
A: Trivex lenses tint best when combined with a tintable hard coating as the tint is more readily absorbed into the coating. Trivex material itself can be difficult to tint but again if combined with the proper tintable hard coating it may be able to be tinted. As far as compatibility with AR coating – Trivex is compatible with all AR coatings and no manufacturers have reported any issues or problems. Any “bubbling” or “pinhole” defect is most likely related to the tinting process and the lens not being tinted properly. When tinting Trivex and then applying an AR coating – labs generally have to over tint the lens as some of the color is removed during the AR process so in order to match the requested color labs often times have to add more color than needed and gauge the amount the will be released during the additional processing and sometimes because of this the lens may be tinted more than once and this could affect the tintable hard coating so any defects seen would be a result of the tinting process and note specifically related to the Trivex material. Tinting does not affect impact resistance. Q: I was surprised to hear that the UV blocker wears off. How would I explain to my patient that it wears off and cannot be replaced if lenses are still in good condition and prescription has not changed, and it cannot be replaced. Therefore not protecting the eye from UV.
A: Whether or not the UV protection can be replaced is dependent on what other coatings are on the lens – if it is a lens with no other coatings than it may be able to be re-applied. I would mainly be concerned with CR-39 or plastic lenses with no other coatings except the UV absorber – In other lenses and coatings the UV protection is part of the lens and should not wear down. With CR-39 or plastic lenses in which a UV dye was used – this is the case where as it may wear off over time or reduce its efficiency. In these cases I would simply ask the customer to come back every 6 months to have their glasses re-checked for proper absorption efficiency Q: How long does it take for the UV coating to decrease to a level that it becomes ineffective?
A: UV coatings or dyes can wear off over time but it is dependent on many conditions such as amount of exposure to UV, environmental issues, types of cleaners or solvents used etc…Unfortunately there is no specific answer to this so I would recommend asking customers to bring back their glasses to have the UV absorption re-tested and validated periodically – perhaps every 6 months. Q: With relation to Trivex lenses, is there any drop off in UV protection over time as there is with UV coatings?
A: Trivex lenses have UV protection build in the material/monomer. That means lenses are produced/cast with the UV protection and therefore it won’t change over time. Trivex lenses will maintain the UV protection over the intended life of prescription spectacles. UV protection decreases over time only if it is added to the lens through a coating, which is not case with Trivex lenses.. Any lens material with UV protection built in should be fine over the life of the prescription – approximately 2 years or so. As with anything, there are so many factors that could contribute to a reduction in the efficiency of the protection but again there shouldn’t be any issue with the effectiveness over the life of the prescription and I would say this is the case with all lens materials with UV protection built in.
. Q: Can you clarify the best materials for rimless glazing - given that many manufacturers will recommend Polycarbonate as the material of choice even though it has poor optical performance, Is Trivex material more suitable for rimless glazing than 1.6, 1.67 or 1.74?
A: Trivex material is considered one of the best materials for rimless glazing given the exceptional impact- and chemical-resistant features of the material as well as its outstanding optical performance. Trivex lenses are extremely durable and tough enough to withstand the stress associated with rimless spectacles, resisting cracks and fractures to which other lenses are sometimes susceptible. For patients with stronger prescriptions, lens materials such as 1.60 and 1.67 can be used for thinner lenses in rimless spectacles, but they may not be as resilient as Trivex lenses.
. Q: Safety Specs: Forgive me if I am out of date on Safety specs! Not an everyday dispense but, given that Trivex material comes via Apache Helicopters (reasonably safe then!) should we as a profession, be suggesting to safety labs that Trivex lenses be dispensed in preference over Polycarbonate insofar as impact- resistancy?
A: Trivex lenses should definitely be considered for safety applications. Trivex
lenses and polycarbonate lenses feature similar impact resistant performance properties and may be considered equivalent with regard to impact protection. However, polycarbonate lenses are not as chemically resistant as Trivex lenses and can also be susceptible to stress-cracking.
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. Q: Dispensing children and sports goggles. Are you confident that the material is as good as safe polycarbonate?
A: Trivex lenses should definitely be considered for children and sport goggles. Trivex lenses and polycarbonate lenses feature similar impact resistant performance properties and may be considered equivalent with regard to impact protection. However, polycarbonate lenses are not as chemically resistant as Trivex lenses and can also be susceptible to stress-cracking. In addition to the durability, Trivex lenses offer optical clarity close to CR-39 lenses, while polycarbonate lenses have the lowest Abbe value of all lenses.
. Q: What thickness should the material be to consider it safe?
A: Trivex lenses can pass the most stringent spectacle impact performance tests at . (Note that coatings may alter the impact resistance of any lens material.) . Q: It's a great alternative to CR39 but how about thickness? Lots of patients even as low as -3.00 want their lenses as thin as possible.
A: While patients say they want their lenses as thin as possible, opticians should recommend a lens with the best overall performance. A combination of optical performance, lightweight comfort, durability, UV protection AND thinness should be the preferred recommendation for every patient. For example, consider a -3.00 D prescription – lenses made from Trivex material will be relatively equivalent in thickness to a 1.60 lens and less than a bank card thicker than a 1.67 lens. Your patients may not notice the difference in thickness but they would benefit from improved optical performance, comfort and safety. If they could notice the difference, they may be willing to accept a slightly thicker lens for the improved all- around performance.
. Q: Do you feel that as UK Opticians (DO's & Optoms), we can get blinkered in our thinking and openness to new products and technologies?
A: Understandably there are a plethora of new lens products being launched on to the market almost weekly (it seems). When you break this down into specifics of design, material and coatings we see that very few new materials or concept in materials has been launched for some years now. And in the past newer materials have almost entirely been aimed towards lenses being thinner and to some degree lighter. Much of this happening though at a time when frame shapes and sizes have not necessarily required higher and higher index! Fortunately the growth in rimless has meant tensile strength and brittleness has been 'front of mind'. Polycarbonate and Trivex allow those whose prescription demands a lower index yet the rimless requirement is different. The 'issue' as I see it is that generally we recommend lens index simply on the basis of prescription and frame size. We need to break this habit. This webinar has succeeded in getting people talking about new technologies and it is this education and training which allows the optician to comfortably detail and discuss with patients the benefits
. Q: What are 1.76 lenses? Are they plastic? What is double aspheric?
A: 1.76 lenses are plastic lenses with high sulfur content (approx. 60%) to increase the refractive index. “Double aspheric” refers to the geometry of a lens in which the surface has been flattened in two axes (or meridians).
Q: Surely the overriding issue for use of new materials like Trivex will be cost - recent. Hi-index lens market growth will be due to huge cost reductions in recent years.
A: Yes, it is true that cost certainly plays a significant role in the acceptance and use of any new lens technology – including materials, designs, coatings and treatments. However, the price of Trivex lenses today is more competitive with other premium materials. In fact, Trivex lenses are less expensive than 1.67 and 1.74 lenses but offer a more complete set of benefits for patients with low to moderate prescriptions (+/- 3.00 D).
. Q: Is there any likelihood of Trivex pricing coming more into line with Polycarbonate?
A: The raw materials and casting equipment used to manufacture Trivex lenses are different from polycarbonate lenses. Trivex material is used almost exclusively to manufacture ophthalmic lenses. Polycarbonate chemistry is used in many other applications – such as plastic bottles, DVDs, and other injection molded products. Therefore, polycarbonate chemistry benefits from economies of scale that Trivex material may never achieve. That said, the price of Trivex lenses today is more competitive with other premium materials. In fact, Trivex lenses are less expensive than 1.67 and 1.74 lenses but offer a more complete set of benefits for patients with low to moderate prescriptions (+/- 3.00 D).
Q: Is Trivex material more expensive to produce than CR39? .
A: Yes, Trivex material is a more expensive than CR-39 material. The raw materials and casting equipment used to manufacture Trivex lenses are more expensive than CR-39 lenses.
. Q: Did your figures for conventional PAL's include non-individualised Freeform lenses?
A: Yes, our figures classified progressive lenses surfaced using digital surfacing equipment (freeform) where only the sphere and cylinder are applied as
“Conventional PAL”. At least one additional “individualized” measurement is required to be classified as “Individual PAL”.
Q:. Is there a budget for manufacturers to market Trivex lenses directly to the consumer, such as the approach taken by Transitions?
A: PPG will continue to work through our lens manufacturer, laboratory and ECP partners to market the features and benefits of Trivex lenses to consumers. We believe that the value of the ECP’s recommendation is ultimately greater than the investment that we could make in an expensive consumer media buy. We are looking to support our Trivex Lens Specialists with the recall letters they could send to the patients, point-of-sale materials to make recommendation process easier from the ECP to the patient and additional optician education opportunities like our recent webinar with ABDO.
. Q: Is there a simple non destructive test for identifying Trivex lenses when dealing new patients wearing lenses of unknown material?
A: No, unfortunately there is not a simple, non-destructive test to identify Trivex lenses.
Q: When referring to high-end entry, coatings and gadgets (upgrading mobile phones etc.) you are considering the patients under the age of say 55 (I’m guessing here). What with our huge over 60's population - most of whom claiming their NHS sight. test, there is an reduced inclination to invest in coatings etc. they are old school patients who see specs as a necessity not an accessory. I do agree that we should better promote new technology but 'selling' the extras is very tricky for a substantial size patient sector. It would be interesting to see the age range of patients used to collate data.
A: Yes, we agree that there is a type of patient who is not interested in a value- added, higher performing product. We believe, however, that we should challenge ourselves to allow the patient to make the decision with the best product offered to them. If an optician declines to offer a value-added product to the patient, there is no way of knowing whether or not that patient is interested. Research shows that 90% of consumers will defer to the recommendation of the eye care professional. We should offer the best products for the patient and allow them to make the decision.
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Q: Does the panel feel that the seed can be sown in the test room by Optometrists regarding new materials/coatings? The DO's can then advise more fully
A: Yes, it can be beneficial for the optometrist to discuss lens options and recommendations with the patient in the exam room. However, a professional optician who is knowledgeable about lens technologies and provides their expert opinion can have as much influence on the patient’s decision. In fact, research shows that 9 out of 10 patients will choose their eye care professional’s spectacle lens recommendation
Q: Phone salespersons always give a hard sell to get consumers to upgrade. Do you think ECP's are afraid of coming across as hard sellers and therefore alienating our. patients? How would you handle to cost aspect of new technology, as many of the new lenses are much more expensive? .A: Many patients are looking for an optician’s professional opinion. Instead of “selling products”, opticians should consider that they are “recommending visual solutions.” Provide the patient with the best recommendation possible supported by a solid understanding of lens technologies and features and allow the patient to make the decision.
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Q: Are Trivex lenses available with Transitions?
A: Yes, Trivex lenses are available in the latest Transitions lens technologies, including Transitions Signature 7, Transitions XTRActive and Transitions Vantage lenses. In addition, Trivex lenses are also available with photochromic technologies from other lens manufacturers.
Q: As technology improves will there be a Trivex 2 which for instance will be thinner, have a higher Abbe value? but still offer its basic advantages. Is there any prospect. of higher index in urethane Trivex type materials?
A: While not a replacement for Trivex lenses, PPG developed Tribrid lenses as an extension of its performance lens material family. Trivex lenses provide the best performance for patients with low to moderate prescriptions. Tribrid lenses feature a higher refractive index (1.60) and similar optical performance and lightweight properties
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Q: What is Tribrid?
A: Tribrid material extends the range of PPG’s premium, performance lens material family. Tribrid lenses were developed using a hybrid approach merging elements of the chemistry for Trivex lens material with traditional higher-index lens chemistry. The result is a thinner lens that provides the patient with a superior combination of performance benefits suited to patients with stronger prescriptions within the range of +/-3.00 to +/-7.00 diopters. Tribrid material features optical clarity (Abbe number 41), lightweight comfort (density 1.23 g/cm3), thinness (refractive index 1.60), impact resistance (up to 5 times stronger than other 1.60 and 1.67 lenses) and 100% UV protection.
Q: Am I correct in thinking that Tribrid lenses have a RI of 1.6 and if so, how does this differ chemically to Trivex lenses. Do they have superior optical properties compared to their 1.6 counterparts as Trivex lenses does compared to CR39?
. A:. Yes, Tribrid lenses have a refractive index of 1.60. Chemically, Tribrid lenses are similar to Trivex lenses; however, there are some key differences in the chemistry that affect the overall properties of the lenses. Tribrid lenses have a 42 Abbe number; Trivex lenses have a 45 Abbe number and CR-39 lenses have a 58 Abbe number.
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Q: Which lens manufacturers offer Trivex lenses in the UK?
A: Trivex lenses in the UK from the following manufacturers/laboratories:
BBGR Berkshire Caledonian Eye Index
Jai Kudo Horizon Hoya LensTec
Norville Quincey Rawdon Riviera Rimless Glazing
Rodenstock Seiko Shamir Sinclair
Tant Younger Optics Waterside WLC
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Q: How large a base curve can Trivex lenses be made in? and will this material eventually replace polycarbonate
A: Trivex lenses are available up to at least a +8 base curve but it always best to check with your preferred lens supplier to get the most up to date availabilities and offerings. As to whether or not Trivex will replace polycarbonate – I don’t think so. I think both materials have a market segment. With polycarbonate you get an impact resistant lens with poor optical quality and with Trivex you get not only an impact resistant lens, you get the lightest weight lens available and much improved optical performance over polycarbonate.
Q: Can coatings be added to Trivex easily? . A: Yes, Trivex lenses are compatible with most coatings – including hardcoat, anti- reflective, anti-fog, mirror, etc., coatings.
. Q: Is Trivex purely 1.53 index?
.A: Yes, Trivex lenses have a 1.53 refractive index.
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Q: Hi, sometimes you will get the odd patient who will not settle in a high index aspheric lens. Would they still have the same issues with Trivex lenses as the Abbe no. is nearer basic 1.5 CR39 and the optical quality is retained.
A: Trivex material may possibly resolve the optical performance issues that some patient experience with high index lenses, particularly if the patient is wearing 1.67 or higher index lenses. The Abbe number for 1.67 lenses is 31 while Abbe
Number of Trivex lenses is 45.
. Q: Is there any provision for this webinar to be made available as a video that could be used as info/training for other staff members? Or even the powerpoint presentation?
A: The video from the webinar and the PowerPoint presentation are available at www.trivexspecialist.co.uk. . .
Q: What happens next to get the CET points ?
.A: The list of opticians who registered their GOC number and watched the entire webinar has been submitted to the ABDO who will then forward the info to GOC. . Once the CET point has been uploaded, GOC will email you notification that your CET point is uploaded.
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. Thank you
For Trivex Lens Specialist Practices, UK
Dora Plisic Trade Manager PPG Optical Materials www.trivexspecialist.co.uk [email protected]