Toshiba has developed a hard disk drive for notebook computers that can hold 100GB of data. The company expects to begin selling it later this year, it said Thursday.

The new drive offers a quarter more storage space than the company's current highest capacity notebook drive and is the first 2.5inch drive from any manufacturer to store 100GB, according to Toshiba.

The company employed a new thin-film technology on both the head and platter to make the drive. That film increased the head's sensitivity and allowed engineers to increase the areal density to 80Gbits per square inch from the current 65Gbits per square inch on Toshiba's 80GB notebook drives, said Midori Suzuki, a spokeswoman for Toshiba in Tokyo.

The company also changed the slider that keeps the drive's read/write head at the correct distance above the disk surface. The new slider is 35 per cent smaller and much lighter than the old one. Its reduced size means the head assembly can get closer to the outer edge of each platter thus freeing up more space for data storage, said Suzuki.

The drive contains two 2.5-inch platters to bring the total capacity to 100G bytes.

Operating shock resistance has also been increased to 325G, which is 50 percent higher than Toshiba's 80GB drive, and power consumption is 20 percent lower on average, the company said. The drive has an ATA-6 interface and speed of 4,200 rpm. Toshiba plans to begin sample production of the new drive in May and expects commercial production to start during the third quarter of this year. Drives manufactured during sampling, when Toshiba produces small quantities of the device for customer evaluation, will cost ¥120,000 (around £600). The company has no estimate for the final price when mass production begins.