Authored by Kieran Blacknall, UK Academy Manager, at Drytac.

Bristol, UK: As the seasons change and we move through the winter, we are all taking steps to ensure we are ready for the cold and wet weather. This might be something as simple as putting on more layers when out and about or making sure the pressure on your car tyres is at the right level.

Failure to prepare for winter is very much preparing to fail; and the same can be said when it comes to the print industry and what you can do to limit disruption at this time of year.

Like most materials, print media will feel the impact of changes in temperature and humidity. If you have ever used a heat gun to stretch a cast film, you will have seen how easily heat can change the structure of a material - and the same is true of the cold.

How will the cold weather impact self-adhesive materials?

First, let us consider the impact of cold weather on typical self-adhesive products. The initial tack level of a typical pressure sensitive adhesive will drop significantly as temperatures approach freezing. This makes it much harder to bond two surfaces together successfully.

This situation creates the need for specialist products, such as Polar Grip from Drytac. This product features a high coat weight adhesive that is aggressive, making it ideal for low energy surfaces, and under the right conditions, can be applied successfully down to -20? C (-4? F).

As temperatures drop, paper release liners can adsorb moisture, expand, and begin to curl, which in turn can create tunnelling problems and cause head strikes as the material moves through the printer. Drytac reduces the chances of this happening by adding moisture stabilising coatings to its release liners, but ultimately paper liners can absorb moisture under the right (or wrong) conditions.

In even colder temperatures, face films can gather condensation and become brittle and difficult to work with, impacting ink adhesion and overall print quality. In contrast, high temperatures can cause adhesives to soften and bleed, paper liners to dry out, and face films to expand and curl as they fight against the relative stability of the release liner. It is important to consider the small, gradual changes that come with the changing of the seasons.

How far has your print media travelled?

Print companies should also consider the journey of their print media before it even arrives at their production facility. How far has it travelled, and could this potentially impact its performance and reliability in an application?

After being manufactured, a roll of print media will probably spend several weeks resting inside a warehouse awaiting purchase. After being purchased, the roll is loaded onto a delivery truck – often in the cold hours of the early morning – before making the journey to your warm, climate-controlled print shop.

This sudden change in environmental conditions is why most printer manufacturers will recommend that media is acclimatised to your environment for 24 hours prior to being used. Acclimatising print media is always good practice during the winter months as a typical roll of media can hold the cold for several hours, which can severely impact the processing capabilities of the product.

Also consider your working environment; this should be kept around 20? C (68? F) and at a relative humidity of 50%. Your print media should be given time to reach this temperature once it has been delivered.

What to do after printing an application?

The cold weather challenges certainly do not end here, with printers well advised to keep a number of factors in mind after the piece has been printed.

Once the product is ready for install, printers should remember that exposure to extremes of temperature can again make the product difficult to work with and should be avoided where possible.

For example, if you have completed a piece of work and plan to deliver it to the customer the next day, do not leave the graphics in a vehicle throughout the night when it is cold. This could lead to unnecessary and easily avoidable issues further down the line.

Where and how should you store your media?

This leads us on nicely to the issue of storage. Print media should be kept in its original packaging, including plastic protective sleeve, suspended on the spool end caps, and kept off the floor to reduce the chances of any dampness rising through the media.

The box should be stored horizontally and away from any direct heat sources or draughts to keep a consistent temperature.

Following these simple steps will improve the quality and lifespan of your print media and give you the best starting product to work with. You can find recommended storage conditions on data sheets available on the Drytac website.