specular PTFE surface

[Lu Wei]

I am seeking a way to have a specular flat surface of PTFE. Is there an
easy or cheap way to do this? Polishing with abrasive paper seems cannot
do this, for I tried polishing glass with abrasive paper only to
roughen it. Maybe coating of glass|mirror? I searched on the internet
that Carl-Zeiss has Teflon coated lenz, but they are for eye-glasses and
not flat. Any suggestions?

[Phil Hobbs]

Post by Lu Wei
I am seeking a way to have a specular flat surface of PTFE. Is there an
easy or cheap way to do this? Polishing with abrasive paper seems cannot
do this, for I tried polishing glass with abrasive paper only to
roughen it. Maybe coating of glass|mirror? I searched on the internet
that Carl-Zeiss has Teflon coated lenz, but they are for eye-glasses and
not flat. Any suggestions?

Well, you could resin-cast it on the surface of some float glass, or
maybe hot press it. PTFE has its glass transition not far from room
temperature, so it's pretty easy to make it flow.

Cheers

Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

[Lu Wei]

Post by Phil Hobbs

Post by Lu Wei
I am seeking a way to have a specular flat surface of PTFE. Is there an
easy or cheap way to do this? Polishing with abrasive paper seems cannot
do this, for I tried polishing glass with abrasive paper only to
roughen it. Maybe coating of glass|mirror? I searched on the internet
that Carl-Zeiss has Teflon coated lenz, but they are for eye-glasses and
not flat. Any suggestions?

Well, you could resin-cast it on the surface of some float glass, or
maybe hot press it. PTFE has its glass transition not far from room
temperature, so it's pretty easy to make it flow.

According to the link given by George H. , PTFE has molding temperature
above 240℃ or 340℃, and "Residual gases (including HF, COF2, CO, and
HFA) that may be harmful diffuse from Teflon® AF resins even at room
temperature. To avoid exposure, all resin containers should be opened
and used only in well ventilated areas using local exhaust ventilation
(LEV)." Though I can find some scraped PTFE materials, I have no proper
heating tools to process it regarding safety concerns at the same time.

[Phil Hobbs]

Post by Lu Wei
According to the link given by George H. , PTFE has molding temperature
above 240℃ or 340℃, and "Residual gases (including HF, COF2, CO, and
HFA) that may be harmful diffuse from Teflon® AF resins even at room
temperature.

You aren't moulding it, just flattening the solid surface a bit. You can try it in a frying pan -- pan, glass, Teflon sheet, heavy weight.

They coat frying pans with Teflon, so the outgassing can't be too bad at cooking temperatures.

Cheers

Phil Hobbs

[g***@gmail.com]

Post by Lu Wei
I am seeking a way to have a specular flat surface of PTFE. Is there an
easy or cheap way to do this? Polishing with abrasive paper seems cannot
do this, for I tried polishing glass with abrasive paper only to
roughen it. Maybe coating of glass|mirror? I searched on the internet
that Carl-Zeiss has Teflon coated lenz, but they are for eye-glasses and
not flat. Any suggestions?
--
Regards,
Lu Wei
PGP key ID: 0x A12F EF75 92CC E1EA

Hmm no idea.. perhaps ask Dupont?
http://www2.dupont.com/Teflon_Industrial/en_US/assets/downloads/h44587.pdf

(I googled optical PTFE coating.)

George H.

[Glen Walpert]

Post by g***@gmail.com

Post by Lu Wei
I am seeking a way to have a specular flat surface of PTFE. Is there an
easy or cheap way to do this? Polishing with abrasive paper seems
cannot do this, for I tried polishing glass with abrasive paper only
to roughen it. Maybe coating of glass|mirror? I searched on the
internet that Carl-Zeiss has Teflon coated lenz, but they are for
eye-glasses and not flat. Any suggestions?
--
Regards,
Lu Wei PGP key ID: 0x A12F EF75 92CC E1EA

Hmm no idea.. perhaps ask Dupont?
http://www2.dupont.com/Teflon_Industrial/en_US/assets/downloads/

h44587.pdf

Post by g***@gmail.com
(I googled optical PTFE coating.)
George H.

Thin film coatings of PTFE can be deposited from the monomer by CVD
(Chemical Vapor Deposition) in a low pressure plasma chamber.
Polymerization occurs on the surface being coated. This process is more
suited to a Carl-Zeiss factory than your home kitchen. If there is any
other way of producing a Teflon coating with decent optical properties I
haven't heard of it.