 |
What are the right eye glasses frame materials for you?There is a wonderful array of eye glasses frame materials. I have summarised the special properties of each below:
PlasticPlastic frames are also known as zyl or acetate. They are made from Cellulose Acetate which is a natural material made from cotton and wood flake. It main advantage is that it is a fantastically versatile material: it comes in a huge variety of colours and patterns. Acetate is easy to adjust with little or no heat and it holds its shape well. For example, your trusty hairdryer could heat up the frame enough to be safely adjusted. Plastic does however get brittle and discolour with age the effects of skin acids. This is why retailers will always shake their heads with a dark look when you ask to re-lens your existing frames with your new prescription. “It’s at your own risk” they say as if daring you to contravene the laws of nature.
A plastic frame will hardly ever break when being re- lensed. Mostly this is just a ploy to encourage you to buy a new eye glasses frame Plastic really does have a good lifespan, it should easily last three to seven years. The frame will go out of fashion before it breaks. There are broadly two qualities of plastic that frames are made from. The world’s leading manufacturer is an Italian company called Mazzucchelli. Every season they produce a dazzling array of new acetate colours which the frame designers choose from to conceive the latest fashion look. Chinese acetate is generally of lesser quality than European. Tell the difference between the two by twisting the front of the frame in your hands to assess the stiffness of the material. Chinese acetate is softer and more pliable which means that the frame will not hold its shape so well. The result is that you may need more frequent adjustments to stop the glasses slipping down your nose.
MetalNickel SilverThe most commonly used metal material in cheaper frames. It holds its shape well and is easy to coat in an array of colours. MonelMost commonly used metal in better quality metal frames. It produces stronger solders and holds its coatings better than Nickel Silver. This results in colour that is less likely to wear and chip off. Most retailers wouldn’t have a clue about the difference between these materials. If asked they could couldn’t tell the difference (unless it said on the front of the dummy lens). They rely on the wholesale price of the frame to give a clue as to quality, and like you they rely on the branding.
TitaniumA beautiful material. It’s very light, strong, easy to adjust, comes in a wide range of colours. It resists corrosion and is great for hot, humid, sweaty environments. It is also nickel free which means that it is hypoallergenic. It comes in a couple of grades: 100% Titanium and Beta Titanium (which is about 95% pure Titanium). From the wearers perspective there is no difference between the grades.
Stainless SteelMade from iron and chrome it is a particularly springy material. It works well for the temples of glasses because it can easily spring back into shape after an accidental bump. It resists corrosion, is relatively light weight and is a cheaper alternative to Titanium. Many Stainless steel frames are also nickel free and are considered hypoallergenic. Memory metalA special Titanium and Nickel alloy. It has the unique ability to remember its original shape after an accidental bending. This means that memory metal frames hold their shape better than the other metals. Sit on the frame and it springs back into shape. Memory frames are lightweight, hypoallergenic and corrosion-resistant.
Are you allergic to your frame?If frame manufacturers are to be believed, then nickel allergy ranks up there with haemorrhoids and pimples as major curses of the human condition. Many frames are sold on their hypoallergenic properties. In reality, hardly anybody has a significant nickel allergy. I might see one patient a year. What is slightly more common is allergy to silicon nose pads. These are the little plastic pads that rest on your nose when you wear a metal frame. Silicon is soft, comfortable and resistant to slipping, but some react to it. If that’s the case then you need to get them swapped over to conventional nose pads that are made out of acetate or PVC.
|
