Suppliers for Apple Inc's new tablet computer have begun shipping touchscreen panels and will start delivering aluminum casings for it next month, sources said, implying a second-quarter product launch.

AVY Precision Technology Inc, a Taiwanese manufacturer of covers for electronic products, will begin production of the cases in February, two sources familiar with the situation said on Friday.

TPK Solutions, an unlisted touch screen panel maker also based in Taiwan will also supply panels for the product, a third source said, on top of those already being manufactured by another Taiwan company, Wintek Corp.

Production of the cases will begin in February, so everything points to a second-quarter launch right now, said one of the sources. It doesn't take that long for the company to assemble the PC together, but a second-quarter shipment date is what we're looking at now.

The sources declined to be named because they were not authorized to speak to the media. Apple's spokesman would not comment. Officials at AVY and TPK also declined to comment.

A barrage of manufacturers are jockeying for attention ahead of Apple's widely expected announcement of a 10- to 11-inch tablet computer in late January, which analysts say could redefine the nascent category much as the iPhone did for phones. Apple has not publicly confirmed its existence.

Hewlett-Packard Co, Microsoft Corp, Dell Inc and Lenovo Group Ltd were among the global technology names that launched thin, touchscreen, multimedia devices this week at the Consumer Electronics Show in Las Vegas.

These wireless gadgets can stream video, download music, surf the Web and play games, aiming to win over consumers by bridging the gap between smartphones and laptops.

Some analysts doubt consumers would take to tablets or slates, which join a market crowded with netbooks, e-readers, smartphones and laptops of all configurations.

Most technology companies do their own design work in-house, but outsource much of the assembly and manufacturing to companies based in Asia, which operate large production facilities in lower cost countries.

(Reporting by Kelvin Soh; editing by Edwin Chan and Andre Grenon)