i-phone's glossy shell

[trxt]

Hello everyone,

Does anybody know the material of i-phone's shell? It is highly glossy and seems like a top coat is applied. Really is there a top coat? or mirror like polished mold surface?
someone said me that there was a special material named "piano black" but i am not sure..
Thanks for your helps..

 

[patprimmer]

I don't know, but as it is supposed to be a very high quality product, it's probably polycarbonate and piano black is probably only the colour. It is quite likely top coated with clear to improve the scratch resistance and to add extra depth to the gloss.

Regards
Pat
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[MacGyverS2000]

As far as I'm aware, "piano black" is a description rather than a material. It describes a carbon black color with a deep, glass-like gloss coat, similar to what you find on a quality piano. Many pieces of electronic equipment, particularly televisions, now come with "piano black" bezels.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[trxt]

You are right mcgyvers. This is the name of finishing. How can i apply this piano black finish? Top coat with clear should be very expensive way to apply all these electronic equipments.

 

[patprimmer]

You can use a black compound with vey fine particle size carbon black and or black dye like nigrosine and a very high polish on the mould and use a hot mould when moulding. This may give a goo deep gloss, but it will alwas be better with some clear on top.

Regards
Pat
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[trxt]

thank you patprimmer. but top coat operation is very expensive and demanding operation as you know. I dont think that all these equipments and tv bezels are all clear coated.

I think that i found the right blend from basf.Has anyone tried this blend?

First high-gloss ABS specialty in BASF’s product line
The new Terluran® BX 13036, a blend of PMMA and ABS, combines the properties of both components of this blend: the special ABS provides the requisite mechanical properties while the PMMA component ensures scratch resistance, high gloss and good color depth. The so-called piano lacquer look is intended not only for black tones; the trend is moving to¬wards white surfaces for electrical devices and household appliances. The new material is being introduced into the market.

 

[Demon3]

Hi trxt,

The way to achieve really deep black is to use a transparent, colorless polymer. When you see a black Chanel lipstick, that is MABS with black added. Because it is a clear polymer, you get the depth of color that is normally achived by adding a clear coat on top. PC would work too, so would PS or SAN depending on your other requirements.

ABS is not a good choice because it's milky and so you don't get a deep black and you don't get the depth effect. The PMMA added to the ABS makes MABS (BASF calls their Terlux) which is transarent, see above.

The very best effect is from using a clear top coat but that costs a lot.

From cheapest to most expensive:

Very cheapest PS, no impact resistance, no chemical resistance

SAN no impact resistance, good chemical resistance (Chapstick dispersers are made of this)

PC Great impact resistance, poor chemical resistance

MABS Good impact resistanc, good chemical resistance

PC and MABS are about the same cost per unit volume because MABS is less dense than PC.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[trxt]

Hi Chris,

thank you for your helps and explanations. I will start to try with MABS..

thank you all for the helps.

 

[sizzer33]

Hi,

MY guess is high gloss black PC/ABS or PMMA. Mould have to be polish real well. The part will then be sprayed with a top coat UV paint to get the piano black effect.

 

[sizzer33]

Hi ,

For Piano black material, check out with Sabic. They should know the type of piano black you're talking about. ITs a PC material by the way.

We got a couple of parts in production here with "Piano Black" resin.

regards,
Ken Chong

 

[Demon3]

Just a note that I know from experience that GE / SABIC salesman will try to tell you that the color you want has to be in polycarbonate. Needless to say it's not true. You can get those colors in whatever transparent polymer you want and in many cases cheaper than you can in polycarbonate. Chose the polymer that's best for your application then get the color you want.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[trxt]

Last month , i was in china for plastic fair and was confirmed that iphone back cover is PC.

 

[Demon3]

Polycarbonate is great for impact resistance but will crack as soon as any solvent (nail polish remover, some cleaning fluids) touch it.

Luckily for us plastics people, there is no ideal plastic, just the right compromise for each application.

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[Squelch]

Hi

TV fronts are made today using the steam mold process which gives the high gloss finish by having the tool temp during the injection stage at the Glass transition point followed by a rapid cooling cycle.

Almost all hand held devises today are made using foils that are printed thermoformed and then back molded. It gives the high gloss finish and in most cases UV curing gives the high scratch resistance.

Piano black is a current look. It is in fact a little abused as it is derived from the deep gloss look on a piano which is achieved with lots of polish and layers of paint. There are many people trying to replicate the look obviously with different levels of success and for different applications.