Why acetate eyewear doesn’t in good shape?

1. The main cause of this issue is insufficient of heat acetate. It cause front and arms not fit the shape of a persons head. If insufficient of heat acetate, acetate eyewear, sunglasses will have some kinds of not good changes.

Acetate eyewear arms
–One change is that arms are too straight and do not have enough curve to fit the shape of a persons head.

Acetate eyewear front
–Other change that front too much curved inward and it makes arms very close to each other.
Too close between arms will causes the acetate eyewear very uncomfortable to wear for customer

–Another change is that front too straight and it makes arms very far away each other.
It causes the frame very uncomfortable to wear for customer

Aoker manufactory has detailed rules and addition steps for heating acetate.
The other manufactory doesn’t have time enough and addition steps for heating acetate compared with Aoker.

2. Maintain shape problem (it involves fix front, arms, arm opening size, screws tightness etc…)
Usually Maintain shape is processed by very skilled stuff. It is to make acetate eyewear in good shape and comfortable wear. But if insufficient of heat acetate, even if the stuff maintain shape perfectly, after a few time, the acetate eyewear must be loose shape quickly.

BTW, the acetate eyewear in folding condition in retail packing for a long time, it can cause right arm less curved than left arm. This is due to the gravity of acetate eyewear makes right arm less curved. So when maintain arms, right arm need curved a little bit more than left arms, in this way, the gravity of acetate eyewear will make the equal curve of arms. Aoker manufactory realized this issue.

Why Handmade acetate eyewear use CR39 lens

CR39 lens with high optical clarity and high abrasion resistance, yet half the weight of glass lens. CR39 material is widely used on prescription lens, as a premium optical grade lens, the price is high.

Is there any other lenses that is better?
No other lens that better than CR39 lens on handmade acetate eyewear, (Lens material range: AC,TAC, PC, Nylon, Mineral glass, CR39 lens)

Compared with mineral glasses lens, CR39 advantages as below :
Light transmittance
CR39 lens 92%
Glass lens 91%
CR39 better than Glass lens on light transmittance performance

Specific gravity
CR39 lens 1.32g/cm3
Glass lens 2.54g/cm3
CR39 half the weight of Glass lens

Drop ball testing(16g Steel ball 1.27m free-fall)
CR39 lens Not broken
Glass lens Broken
CR39 unbreakable than Glass lens

UVA&UVB protection
CR39 lens 390nm
Glass lens 290-300nm
CR39 provide 100% UVA and UVB protection, better than Glass lens

Refractive index
CR39 lens 1.502
Glass lens 1.523
The refractive index of CR39 lens equal with Glass lens

CR39 lens 2.0mm
Glass lens 2.0mm

Atomization trend
CR39 lens better than Glass lens

CR39 lens  Easy colored
Glass lens Not easy colored

As a professional handmade acetate eyewear manufactory, we are using optical grade CR39 lens which pass EU, AU, UNITED STATES standards.