HP d640 HP D640 High-Volume Printer - User Manual (Printer and Accessories), C - Page 254

Purchasing, Handling, and Storing Storing Adhere to the following guidelines when stacking and storing print media: • DO NOT store cartons of reams directly on the floor; cartons should be placed on a pallet or on shelves. • DO NOT store individual reams in such a manner that they will curl or warp along the edges. • Rewrap partially used reams of paper before storing. • DO NOT stack more than six cartons high. • Stack each carton squarely on top of the one underneath. • Stack each carton upright. • DO NOT place anything on top of paper, regardless of whether the paper is packaged or not. • Store envelopes in a protective box so the edges will not be damaged. • Keep stored media away from extremes in temperature and humidity. • DO NOT store printed documents in vinyl folders (which may contain plasticizers), or expose the documents to petroleum based solvents. Environmental Considerations Media should be protected from temperature and humidity extremes. D640 printers are designed to operate in a wide range of environmental conditions, but for best performance, media should be stored and used at 59°F to 95°F (15°C - 35°C), with a relative humidity of 40% to 60%. When media are used in an environment outside the ranges of temperature and humidity shown above, follow these guidelines: • DO NOT leave the media exposed to humidity or temperature extremes. Any extreme changes in the environment will cause the media to take on unwanted characteristics if left unwrapped or in the input tray of the printer. • Where humidity extremes occur, store paper in an airtight container, or seal it in plastic. • If there is a significant temperature difference between the media storage area and the printer's operating environment, allow the media to adjust to the temperature in the printer's operating environment before unwrapping. The greater the temperature difference and the greater the amount of media to equilibriate, the longer this time period should be. Allow one day for every 20°F (10°C) difference in temperature between storage environment and printing environment. Paper is affected by temperature and humidity variations during transport, storage, and use. When the atmosphere is moist, paper tends to have wavy edges; conversely, when the atmosphere is dry, paper tends to have wavy centers. D-18 Using Paper