How Humidity Affects Printers

The term hygroscopy refers to the phenomenon of attracting and retaining water molecules from the surrounding environment. Paper is quite hygroscopic, so ambient humidity and changes in temperature can influence its weight, thickness and rigidity. This can cause a variety of issues in moist environments, especially when printers are involved. Thus, it’s important to understand how humidity affects printers and ward off potential problems before they occur.

How Humidity Affects Printers

Paper’s propensity to absorb water can affect the function of printers in moist environments. If you want to explore how humidity affects printers, it’s important to note the impact depends on the type of printer and paper. However, the following observations typically apply.

High Humidity

When a printer resides in a humid environment, the moisture content can distort the paper, making it warped, wavy or curled. This can disrupt the function of the printer and cause paper jams. It can also cause streaks and smudging during the printing process, diminishing the print quality. Finally, pages may stick together, printed sections may become overly saturated and toner may peel from the page (leaving blank spots).

Low Humidity

When humidity is removed from the air surrounding a printer, multiple sheets of paper may feed at the same time. This is especially frustrating when printing double-sided sheets. Dry paper is also more prone to static electricity, which can cause the paper to jam in the printer. In addition, dry air can cause ink clogs, very light or faded printing and/or text and images appearing to spread out or repeat due to paper shrinkage.

Don’t Forget About Heat

Humidity isn’t the only environmental factor that can affect your printer. Heat can cause moisture in paper or the surrounding air to evaporate, lowering the moisture content. It can also affect the viscosity of the ink. Ink viscosity increases at lower temperatures, which can restrict ink flow and print density. It can also cause mottled print and excessive linting (when dust, lint and other loose material collect on printed surfaces). At high temperatures, ink lowers in viscosity and over-emulsification can occur. Heat can also lead to ink dripping, misting, spitting or smearing.

When it comes to heat and humidity, it’s crucial to strike a balance that protects the quality of the paper and the operation of the printer.

Heat, Humidity & Label Media

Of course, heat and humidity also alter label media and label printers before and after the labels are applied. When labels absorb water from humid air or confront high temperatures, they may fade, lift or curl. Soft-pressure adhesives may fail and cause the binding to liquefy or smear. In addition, quick changes in temperature can cause labels to curl and peel because the label liner absorbs more moisture than the substrate (especially film substrates with paper liners). This happens to all kinds of labels, including roll-fed, die-cut, continuous and fan-fold labels.

When heat and humidity adversely affect labels, this can damage other equipment involved in the process, including printers and auto-labeling equipment. The labels may become jammed within the equipment or residue may build up on the equipment and damage components, e.g., print heads.

How to Protect Printers & Paper

Printers are surprisingly sensitive. Factors like humidity and temperature tamper with the printing process. By managing air quality and airflow, you can help printers function properly in less-than-desirable operating conditions. To protect your equipment and supplies, prevent paper jams and similar issues and preserve the quality of your printed documents, DustShield encourages you to follow these guidelines:

• Choose your labels carefully – Some label stocks should only be used and applied at cooler temperatures-they can become soft, tacky and difficult to apply in hot, humid facilities. Always select label stock approved for high temperatures and humidity if these are a concern in your environment. In addition, try paper labels on polypropylene liners, which are more resistant to moisture and humidity.
• Store paper and labels in an enclosed space – This space should be dry, flat and easily accessible. Typically, it should also remain at room temperature with a relative humidity of 40-60% (review your specific product’s guidelines). Keep the space away from doors, windows and vents to protect it from temperature and humidity fluctuations. Store paper and labels on a low shelf or rack to reduce their exposure to the high temperatures often found on higher racks. Finally, when storing label rolls for barcode label printers, do not lay them flat. Instead, stack them vertically or utilize rack storage.
• Keep paper and labels in original packaging until use – This will prevent physical damage, e.g., tearing, wrinkling and folding, and preserve the paper’s quality, e.g., moisture content and weight. If you do not use all the paper at once, reseal the package securely with tape.
• Store printers in a climate-controlled enclosure – A heavy-duty, industrial-strength enclosure can protect your printer from the surrounding environment. In addition to warding off dust and debris, it can provide a consistent temperature and humidity. This will ensure that your printer remains operational no matter how dry, humid, hot or cold the ambient air.
• Measure and control humidity levels – Printers require a consistent level of humidity, typically somewhere in the range of 40-60% relative humidity (again, check your specific product’s guidelines). Measure the amount of moisture in the air regularly using a hygrometer and add or remove humidity as needed. Heating systems and air conditioners can remove humidity from the air; humidifiers and evaporative coolers can add humidity.

Enclosures to Control Environments

Now that you know how humidity affects printers, are you ready to purchase an enclosure to protect your equipment? A quality enclosure will allow you to control the environment surrounding your printer, protecting it from extreme temperatures and moisture levels.

DustShield offers an extensive line of computer enclosures that are industrial strength, factory-floor ready and designed to protect LCD monitors, tower and desktop CPUs and printers. Our enclosures are delivered completely assembled and suit a variety of applications. We offer customer-driven designs and customizations, and we can enhance any of our standard enclosures with little increase in cost. We would be happy to work with you to create a design that accommodates your wants and needs.

If you would like to protect your valuable equipment from harm and ensure you can carry on with business as usual, check out DustShield’s computer enclosures today. To learn more, please contact our enclosure specialists at 417.736.3746 or sales1@amprod.us.