It can indicate ink low and ink finish.

具有墨量低和墨尽提示功能。

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Metal complex solvent dyes: wood stains, leather, paper, printing, neutral ink, low temperature baking paint etc.

色精主要用在：木器涂料、皮革涂料、纸张涂料、纸张着色、印刷油墨、中性墨水、低温烤漆等等。

youdao

Before HP brought us the low-priced ink-jet printer all office printing was black.

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More than 20 million flexible plastic displays are on the market today, according to Sriram Peruvemba, vice-president of marketing for E Ink, the company that developed the low-power display technology for the Amazon Kindle and many other e-book readers.

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Or, to modernize it, selling the printer at a low price in order to profit on the toner or ink .

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