Frame Materials

Two frames of the same shape can behave completely differently on your face. The reason is usually the material: what it weighs, whether it can be adjusted, and how it ages. Here is what you will meet, and who each one suits.

Acetate

Cellulose acetate is a plastic made from cotton and wood fibre. It arrives as a coloured sheet and the frame is cut from it, which is why the colour runs right through the material instead of sitting on the surface — a scratch does not reveal a different colour underneath. It is the reason tortoiseshell, layered and translucent frames look the way they do.

Suits: anyone who wants a frame with presence, and anyone with a strong prescription — a full acetate rim hides the thickness at the lens edge. It warms and adjusts well in the shop, so the fit can be tuned to your face.

Worth knowing: it is heavier than metal or titanium, it relaxes slightly over time and needs an occasional re-tighten, and it dislikes heat. Leaving a frame on a car dashboard is how good acetate goes out of shape.

Injection-moulded plastic and TR-90

Moulded rather than cut, these are light, springy and inexpensive. TR-90 is a nylon-based material that bends a long way and returns to shape.

Suits: sport, children, anyone hard on their glasses, and anyone who wants to forget they are wearing them.

Worth knowing: the flexibility that makes it tough also makes it difficult to adjust — it springs back to the shape it was moulded in, so there is less we can do to tailor the fit.

Metal

Most metal frames are a nickel alloy, usually monel, then plated. They are light, thin, and take an adjustment well, which is why they remain the quiet workhorse of eyewear.

Suits: anyone wanting a discreet frame, adjustable nose pads, or a minimal look.

Worth knowing: plating wears through eventually, usually at the bridge or where the temples touch the skin. If metal jewellery irritates your skin, the nickel is normally the cause — say so and we will show you something else.

Stainless steel

Stronger and thinner than monel, corrosion resistant, and often left unplated. It contains some nickel but releases very little of it, so it suits most people who react mildly.

Titanium and beta-titanium

Very light, very strong, completely corrosion resistant, and hypoallergenic — the best answer for skin that reacts to metal. Titanium holds an adjustment without needing to be reset every few weeks. Beta-titanium is an alloy with far more flex, which makes it the usual choice for thin temples and for rimless frames, where the metal has to take the strain of the lens mounting.

Worth knowing: it costs more than monel, and for good reason. If you have ever bent or corroded a metal frame, this is the material to move to.

Aluminium

Light, stiff and anodised in colours you cannot get any other way. Less adjustable than steel or titanium, so the fit has to be right off the shelf.

How the frame is built

Full rim — the rim surrounds the lens. The strongest construction, the best at disguising thick lenses, and the most forgiving to repair.
Semi-rimless — a rim across the top and a fine nylon cord holding the lens below. Lighter to look at; the cord is a consumable and can be replaced.
Rimless — the lenses are drilled and the frame mounts to them. The lightest and most discreet, but the lens shape has to be cut for the mount, the lens material has to tolerate drilling, and very strong prescriptions are not a good match.

Hinges, pads and bridges

Sprung hinges flex outwards past their stop. They are comfortable, forgiving of heads slightly wider than the frame, and have more moving parts to go wrong.
Barrel hinges are the plain kind: fewer parts, easily tightened, and easy to service for years.
Adjustable nose pads let us set the height and angle of the frame precisely, and lift the lenses off your cheeks. Silicone pads grip; they perish over time and are replaced cheaply.
Fixed bridges on acetate frames have no adjustment at all, so the bridge must match your nose as made. If your bridge sits low, look for a frame with adjustable pads or one designed with a raised bridge — it is the single most common reason glasses slide down.

A short answer to the usual questions

My skin reacts to metal. Titanium, or acetate.
My prescription is strong. A smaller full-rim frame, acetate for preference.
They feel heavy by the afternoon. Titanium or TR-90, and a bridge that carries the weight properly.
They keep sliding down. Usually the bridge or the adjustment rather than the weight. Bring them in.
I am rough on glasses. TR-90 or stainless steel, sprung hinges, full rim.
I want them to disappear. Rimless or semi-rimless in beta-titanium, if your prescription allows.

Looking after them

Rinse under lukewarm water, a drop of mild soap, then dry with a clean microfibre cloth. Not your shirt, not a tissue, and not hot water. Keep them in a case rather than face-down on a table, take them off with both hands to stop the frame twisting, and keep them out of the car on a hot day.

When something does go wrong, see Repairs & Adjustments. Materials are easier to judge in person — come and pick a few up at any of the studios, listed on Find a Studio, or browse Eyeglasses and Sunglasses.

Contact

Phone and WhatsApp: +91 75750 01691
Email: contact@chashmish.com