( 1 ) THIS order disposes of the plaintiff s prayer for the grant of ad-interim injunction.

( 2 ) THE plaintiff has filed a suit complaining of infringment by the defendant of the plaintiff s patents No. 154388 dated 4. 6. 80 and No. 157991 dated 8. 6. 82.

( 3 ) THE plaintiff is engaged in the manufacture and sale of glass tiles through a partnership firm M/s. Mridul Enterprises wherein he. is a partner besides his father and brother. According to the plaintiff he is actively engaged in research and development work relating particularly to glass tiles. The glass tiles made in India had a few disadvantages such as the edges of such tiles were sharp which could cause injury; surface of the tiles was not smooth and was devoid of aesthetic value and it had a tendency to get displaced when applied to ,a wall surface. Such tiles were produced from molten glass. The plaintiff s research invovling considerable expenditure and effort resulted into a solution forming subject matter of patent No. 154388 effective from 4. 6. 80 It related to a glass tile having a front face thereon the distance between two opposite side walls of the front face was smaller than the distance between the side walls in any other plane of the tiles besides the front face. Further efforts, research and developmental work of the plaintiff resulted into a process for the manufacture of glass tiles from crushed glass in departure from the previously known method of producing glass tiles from molten glass. This process of producing glass tiles from crushed glass resulted into the grant of patent No. 157991 effective from 8th June, 1982. The claim No. I of this patent reads as under :-

"a process for the manufacture of opaque or translucent glass tiles which comprises in crushing single Or different glass separately or together to form a mixture of glass of a particle size not less than 10 mesh, compacting said crushed glass under pressure to form a shaped composite, subjecting the shaped composite to the step of heating it to temperature of the order of 800 degree to 900 degree C to allow a further compaction of atleast 5%, said compacted and shaped composite being heated to a temperature sufficient enough to cause a deformation of the edges of the tile and simultaneously polishing of said tile. "the copies of the specifications of the two patents have been filed.

( 4 ) THE plaintiff further alleges that the tile of the aforesaid patents is a definite and distinct improvement with that of the prior art, which is the exclusive right of the plaintiff under Section 48 (2) (b) of the Patents Act, 1970. The defendant has started manfacturing and selling of glass tiles which constitutes an infringment of the plaintiff s patents. Hence the suit which was filed on 15th March, 1993.

( 5 ) LET it be stated at the very outset that in so far as patent No-154388 is concerned, it was conceded at the bar that 14 years term of patent contemplated by Section 53 (l) (b) of the Act having expired by the time the matter came up for hearing, the suit was rendered infructuous to that extent. In the succeeding paragraph the defence to the extent of patent No-157991 dated 8. 6. 82 is only being noticed.

( 6 ) THE principal ground on which the defence is based is that the defendant was using the well known process for manufacturing tiles covered by lapsed patent No-111139 dated 17th June, 1967. The plaintiff,had wrongly obtained patent of a process which was part of a lapse patent and therefore was "prior published". The plaintiff is not entitled to any relief as he has made material concealment of facts and has also made false suggestions. The plaintiff s patent is liable to be revoked and this by itself provides an adequate defence to the defendant which would enable the suit for infringment being rendered unsustainable. The process set out by the plaintiff was not a patentable invention under Section 2 (l) (j ). It was liable to be revoked under Section 64 (1 ) (a) and