"Method for recycling cutting fluid". US20120073952

The basic idea here is to distill the cutting fluid in a low/free oxygen/nitrogen environment. Settle, vaporize (safely), and condense. This is possible with any homogeneous fluid. I don't see here where there is anything novel. Crack it (heat, pressure, or chemical), filter it, or distill it. These are the "common" ways of separation. Anything within this would seem to fail the novelty criteria.

What did the patent office see in this application that is novel?


2 Answers 2


You can read the file history of a US patent or published US Patent application on Public Pair

The patent examiner issued a notice of allowance ("NOA") for this patent on 4/15/13 following an interview with the inventor(s) by telephone. The text from the examiner's NOA is as follows:


The following is an examiner's statement of reasons for allowance:

The claimed invention is directed to providing a method for recycling cutting fluid, which can be processed with a high recycling rate of cutting fluid. See page 2, lines 15-17, of the specification.

The claimed invention specifically provides a method for recycling cutting fluid comprises a step of "separation," by preparing and oxidizing a cutting fluid of silicon including a silicon mixture and a cutting fluid at 150C to 350C in a container, to obtain a vaporized cutting fluid and a silicon slurry; and a step of "recycling," by condensing the vaporized cutting fluid to obtain a recycled cutting fluid. See page 3, lines 2-7 of the specification.

No such combination of methodprocess is disclosed or suggested in the cited references of record.

Thus, the subject matter of claims 1-5 is neither disclosed by the prior art nor is obvious. The claims are deemed allowable over the prior of record.

The applicant disclosed as prior-art:

The examiner cited as prior-art:

  • Patents 5,795,400, 8,029,756, US patent application 2010/0061913 and no non-patent documents

I'm not familiar with technology described in this patent. So I can't speak to whether the invention as described is obvious.

However, if the invention is in fact obvious then this is a good example of why we need to submit prior art to the USPTO within six months after a patent application is published. Under the America Invents Act the patent examiner is allowed to consider any prior art we submit.

AskPatents.com was designed to facilitate the submission of prior art to the patent office during the patent prosecution process. Any interested party can post a Request for Prior Art ("RFPA") on Ask Patents. The interested party is encouraged to answer his own question with any prior art he can cite.

Once a patent is issued it is presumed valid and a re-examination is much more difficult.


edit: See other answer - It was posted while I was writing my answer. It is more complete. I'm up voting it.

The number you reference is an application publication number, not a patent number. That means, from only what you were looking at, nothing was granted. If you look the case up in the USPTO's public PAIR it got a notice of allowance in mid April 2013 - today that is last week. The only rejections it looks like it got were of wording, not substance. The examiner cited three documents as the closest.




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