快猫短视频

THE next revolution in panty liners will be ones that change colour to warn
women they are about to ovulate. They can also tell if a woman has an
infection鈥攐r even when her period will start. Healthcare companies are
scrambling to patent the new approach first.

In the early 1990s, Media-Pharma of Germany, Kimberly-Clark of Wisconsin and
several private inventors separately filed patents on the idea of impregnating
sanitary towels and diapers with chemicals that changed colour according to the
concentration of glucose and nitrites in blood and faeces.

Now Procter & Gamble, maker of Always and Tampax, has filed a string of
world patents. They detail how in tests women wore panty liners impregnated with
gum guaiac wood resin, which turns blue in the presence of tiny traces of blood,
and a pH sensor such as carminic acid, which turns red between
pH 4 and 7. These markers turn purple four hours ahead of menstruation,
giving the wearer plenty of notice.

The panty liner that pinpoints ovulation has a plastic film coated with
amorphous silicon that changes thickness slightly in response to changes in the
levels of oestrogen, progesterone and follicle-stimulating hormones. The
thickness change alters the path of reflected light to create a purple spot on a
gold background.

P&G鈥檚 patents also say they will be able to test for pregnancy and detect
substances which signal bacterial, fungal and viral infection, including
Escherichia coli, Salmonella, thrush, Chlamydia and HIV. Canadian
and South African researchers are also developing disease detecting sanitary
wear鈥攂ut these need to be analysed in a lab
(快猫短视频, 30 September 2000, p 19).

When these products will reach the supermarket shelf is unclear. P&G鈥檚
Sally Woodage would only say: 鈥淲e never comment on upstream development areas.鈥�