Thermax Standard & Custom Irreversible Temperature Labels

Product Bulletin

 Thermax® irreversible labels have been updated with a new temperature indicating chemical for the 232ºC / 450ºF& 199ºC/390ºF events.

 Glenview IL – March 21, 2019 – All Thermax standard and custom labels utilizing the   232ºC / 450º & 199ºC /390Fº  temperature events have been updated with this new chemical. Extensive accuracy, stability, compatibility and accelerated aging tests have been performed to ensure that the new chemical meets company quality standards and are available upon request or by clicking here. This update is part of LCR Hallcrest / Thermax’s ongoing commitment to delivering superior temperature indicating products that perform as indicated .

 Call 847.998.8580 or Email: [email protected]  for further information                                                                                                                                                                           

Testing Procedure For 232 Melt Chemical.

Initial batch prepared by R&D.  Melt point of un-milled chemical tested. 

Start 231.8 mid 233.0   End 234.2     Specification – mid point should be between 228.7 – 235.3C

Determined to be within specification so chemical made into a dispersion and coated on coating machine.

Non- encapsulated paper sample applied to Linkam, heated 10C above rating and removed from stage.  Sample applied to Chemical approval sheet and checked for reversion not occurring after 1 month.  If reversion or any apparent reaction has occurred this would be recorded.

Sample of the coated paper taken to production and put into machine made indicators.  No issues in machining the coating were reported.  Coating quality noted.  Melt point checked on finished label. 

Indicators melt point was tested at standard heating rate of 2C / min and 20C / min.  Passed on meeting accuracy specification.

2C / minute   Start 230.4   Mid 232.3   End 234.1     20C / minute   Start 230.8    Mid 233.7   End 235.7

An accelerated aging test is carried out by putting a coated paper sample in an oven at 150C for 24 hours normally.  In this case the chemical was kept at 150C for 96 hours.  A sample was then taken and made into an indicator.  The melt point was retested to ensure chemical decomposition had not occurred. 

Start 230.7   Mid 232.2   End 233.6

Compatibility with adjacent chemicals in a label was checked.  Hand-made 3 level labels was prepared with 224, 232, 241 chemicals.  Initial melt points were measured on Linkam.  No problems were recorded.  A second sample was given an accelerated aging test by keeping the label in an oven at 150C for 24 hours.  The melt points of the label were checked, and no problems were seen.  All results recorded on chemical approval form.

Having performed satisfactorily repeat batches were synthesised in two laboratories – Deeside production and Honiton R&D to ensure repeatability.  These were coated at Deeside.  Melt point tests were run at Honiton in hand made labels. 

A 24hour aging test at 150C was carried out on the new paper.  It showed no deterioration in colour and when put into a label changed in specification.

All test results recorded on a chemical approval form along with samples of indicators / paper coatings.   All tests carried out were passed, melt point accuracy, compatibility and stability passing.

Raw Material Change Notification

199°C Melt Chemical

Due to issues with the synthesis and the chemical constantly reading on the high side of the temperature tolerance for 199°C a new 199°C melt chemical (internal code 199.1°C) was sourced to replace the existing chemical.

The new 199°C that is being introduced is chemically similar to the previous one but has a lower melt point which brings it well within specification and gives improved yields in production.

Testing:

Conclusion:

The new 199°C (199.1°C) shows improved accuracy and excellent stability at high temperatures both on its own and alongside the other chemical coatings in its range. The chemical is easier to manufacture with improve yield and better accuracy. Due to this it is planned to move all irreversible label production to 199.1°C melt chemical.