This law is, as you probably know, one which was implemented in 1998 to allow companies to store their accounts (or books, records = choubo) electronically, such as on recordable CD, rather than having to keep records on paper, as they had been required to do hithertoo.

The full and official name for this law is
電子計算機を使用して作成する国税関係帳簿書類の保存方法等の特例に関する法律
(see first of references below) but since that is longwinded it is generally abreviated to the form you give. The translation I have given is found in the second of the two references given below, and approaches a translation of the full and official name. Useful translations of the abbreviation might be

Electronic Preservation of Records Law
Preservation of Electronic Records Law
Electronic Storage of Accounts Law
(or some permutation of the above)

More information on this law at -
http://www.kt.rim.or.jp/‾saito/month/9801/9801tax-e.html