Dear Mr. Banker,
Although, you asked for book name, I will comment on the real scenario to be considered while patent drafting.
Patent draft is a techno-legal document.
1) Drafting starts from analysing the prior art and first on concluding your invention by differentiating it from prior art.
2) Once decided the actual invention and its scope to cover in patent claims, look at the country's patent rules. Like in India look at section 3 and 4 for deciding whether your invention is liable to be rejected on any of the provisions of those sections. (For Europe: EPC article 52, For US: 35 U.S.C. 101 and 102)
3) Once crossed this hurdle, draft the claims first and then draft the descripttion and background part.
4) Claim drafting is of atmost importance and claim shall have preamble, transitional phrase and body. Claim shall not be too narrow and shall not be over claiming than actual invention. Any future claim amendment (while prosecution phase) may drastically narrow down scope of claim and even may take away the benefit of applicability of Doctrine of Equivalents during suit for infringement of patent claims. It may also give the opportunity to opposite party to plead mala fied intention while drafting claims.
5) Descripttion shall be enabling the claimed matter. Enablement means reproducibility of claimed invention by reading the specification by a person ordinary skilled in the art. Here the words "person ordinary skilled in the art" has great importance.
At the same time for the benefit of patentee the descripttion shall not disclose the trade secrets and know how.
Ultimately this is a skilled job which balances the written requirements for patent grants and also take care of secrecy for client's interest.
6) You may get many books only defining outline of patent specification but the real drafting skill is developed only through studying infringement cases, prosecuting the patents at Patent Offices (replying the objections and convincing at hearing), litigating, opposing patents etc. Because that gives you confidence for drafting on your own.
There are much more intricacies and sections and rules to be looked into while drafting a patent specification. So study and full knowledge of entire Patent Act of concerned country is very much necessary and important.
With due respect, I would say that hoping that, I have made clear the real scenario in front of you. Please feel free to mention your difference in opinion. Ultimately, Patent drafting is the skill acquired through experience.
Parag M. More
IPR Consultant, Patent Attorney
M.Sc., LLM - IPR & IT