TAPPI T544 Aging of Paper

TAPPI T544 Aging of Paper and Board: Moist Heat Testing

TAPPI T544 evaluates the humidified treatment of paper regarding long-term aging qualities. As a certified environmental lab, we realize the importance of TAPPI T544 environmental testing. Meeting the environmental and TAPPI standard requirements can be difficult. We understand the challenges and guide companies through the process.

Keystone provides the peace of mind that all of your needs will be met. Our test reports are delivered quickly. We take a consultative approach throughout the entire test program and create an accurate test plan to eliminate expensive over-testing. Lastly, Keystone partners with customers to achieve environmental product compliance. 

Request a quote to receive testing services tailored to your specific requirements. Contact us to receive more information on our expert TAPPI standard environmental testing lab.

Summary of TAPPI T544 Transit Integrity Testing

The T544 standard test method specifies the procedure for humidified heat treatment of paper or board. The environmental test also gives general procedures for the testing of heat-treated materials. The purpose of TAPPI T544 integrity compliance is to obtain information regarding the long-term aging qualities of paper.

Additionally, the TAPPI T544 standard test method is based on work done on printing and writing papers but may be used for other types of paper and board.

Exposure of paper or board to a hostile environment may cause natural changes in the material and degradation of paper stability with regards to its ranking. The hostile environments mentioned above include elevated temperatures or chemical attacks over a period of hours. Hostile environments that have been used include but are not limited to exposure to heat and moisture, visible ultraviolet radiation, sulfur dioxide, and nitrogen dioxide.

Scope of Environmental Paper and Board Moist Heat Testing

TAPPI T453 “Effect of Dry Heat on Properties of Paper” is available for evaluating the effects of dry oven treatment on paper. The degradation rate of cellulose is very sensitive to the amount of moisture in samples. Comparison of accelerated aging with natural aging indicates that some moisture should be present in an accelerated aging atmosphere.

A specimen is selected at random and prepared for a recommended seven sets. It is important to avoid handling test specimens with fingers. This will avoid undue exposure to the atmosphere of a chemical lab.

Data included in this standard test method covers the following:

  • Complete identification of the sample
  • Date and place of testing
  • Time, temperature, and relative humidity of testing
  • Mean value and precision of the measured value of the appropriate property of the untreated material
  • Any deviations from the relevant TAPPI methods or other methods used

TAPPI T544 Standard Environmental Testing Procedures

Prior to testing, one set of untreated specimens and aged specimens are preconditioned overnight. These are pre-conditioned to a temperature of 23 degrees Celsius and 10 to 35% relative humidity. 

The test specimens are first installed in an aging vessel adjusted for the internal temperature to be 90 degrees Celsius. One set of test specimens is retained as a control.

Dry air is then passed through the aging vessel at a rate of about 500 mL per minute. This is done for about 10 minutes. Next, the rate is lowered to around 50 mL per minute for the duration of the aging period.

One set of test specimens is removed at each of the following times (in hours) or times that were agreed upon from the manufacturer and T544 test lab. These times are allowed some deviation within given conditions: 24h, 48h, 72h, 144h, 288h, and 384h. Next, the sets of test items are suspended in the test chamber pre-adjusted to an internal relative humidity of 50% at 90 degrees Celsius.

It is important that the test specimens do not touch the walls of the oven, or are exposed to radiation from the heating coils.

TAPPI Test Method T 402 Standard Conditioning and Testing Atmosphere for Paper, Board, Pulp Handsheets, and Related Products may be used for estimating the effect of moist heat treatment on papers.

Keystone Offers Expert TAPPI T544 Environmental Testing

Keystone has a full lab of test equipment which permits us to provide short lead times on scheduling. Our team strives to give our customers more time and energy on product development instead of testing.

Our TAPPI T544 testing knowledge and experience expedite the test process and assist our customers with overcoming challenges when they arise. Contact us to receive more information on T544 environmental testing.


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