Activity Feed Forums Printing Discussions General Printing Topics Contravision pulling away from backing paper

  • Simon Worrall

    Member
    October 14, 2020 at 7:35 pm

    Poor quality short term contravision, or unmatched laminate, I would say. I once made the mistake of getting some cheap contravision for a short term job that wrinkled as soon as it unrolled new from the roll and went over the heated printer bed, to the point where I could not even print it without a head strike.

    • Martyn Heath

      Member
      October 15, 2020 at 5:01 am

      This is the “longterm” polymeric stuff. Best i can get my hands on with matching laminate.

  • Robert Lambie

    Administrator
    October 15, 2020 at 2:13 am

    @MartynHeath

    “My arse went”.

    🤣🤣🤣
    That made me laugh!

  • Jamie Wood

    Member
    October 15, 2020 at 8:00 am

    I’d say that it’s the face film expanding at a different rate to the backing, probably due to atmospheric conditions.

  • Graham Scanlan

    Member
    October 15, 2020 at 11:00 am

    Hi Martyn

    I’m not sure what laminate you used a pvc or polyester based, but next time you could try and laminate with less break or tension on the laminator.

  • Martyn Heath

    Member
    October 15, 2020 at 12:10 pm

    thanks guys. Food for thought

  • Robert Lambie

    Administrator
    October 18, 2020 at 4:27 am

    There can be several reasons why this tunnelling of the vinyl appears.

    I believe that the reason is most often shrinkage of the vinyl while on the roll or the shelf-life expectancy of the vinyl has passed.

    When the vinyl is on its core it is wound pretty tight.
    The shelf-life of vinyl is normally 2 years.
    Over this period of time, the vinyl will shrink. it’s not visible as such, but if you look closely at the edge of the roll you will see a millimetre or two of the white liner exposed. You can sometimes see this on swatch-book samples also. Obviously, this will happen more with cheaper monomeric vinyl but happens with polymeric too, as well as some so-called casts!

    Sometimes it’s not just the “time spent on the roll”, but the room it has been kept in. if you have a room that’s hot all day and cold at night. the vinyl is exposed to this varying temperature every day and again, has an effect on the vinyl itself.

    Anyway, you now have a roll that’s tightly wound, experiencing hot and cold temperatures and is shrinking. all very slightly of course, but it now forms and holds this rolled-up shape.

    In this instance, we are talking about a perforated vinyl which has about 50% less adhesion and hold on the lining paper.

    Now, along you come and you lay it out on the table to trim it up, but the tight wound vinyl has still got the memory of that round core and as it rolls out flat. The paper isn’t affected but the vinyl is and wants to keep it’s rolled shape. so it starts to lift and create the tunnels across the width of the roll as the paper liner and vinyl start to separate. which in this case is easy because the perforated vinyl has only 50% adhesion on the lining paper.

    this is very common with polyester and foil type vinyl like the cheap brands of chromes and prismatics. not for the shrinkage but more the forming of the rolled shape due to the time on the roll. if you are “cutting” it, it is even worse because the blade is trying to cut through the tunnels as it zips back and forth while the blades cutting. this normally snags or jams the cutter.

  • Martyn Heath

    Member
    October 18, 2020 at 7:21 am

    Thanks for your detailed response rob. i think you have hit the nail on the head with your explanation and like you said this shows tenfold with one way vision due to the lack of adhesive. Its definatly something i need to be aware of in the future. Print and fit in the same day. Atmosphere wise, the materials were delivered and stored in my printing room for 24hrs before printing. The environment is stable 24hrs a day at a constant 18 degrees.

    So i believe its either a type of vinyl issue or old material.

    The laminator tension issue could have also been in the mix, however ive never had this problem with anyother materials and i dont adjust the tension.

  • Robert Lambie

    Administrator
    October 18, 2020 at 10:23 pm

    The varying temp issue is more a case over time mate. most likely when its in storage at your supplier’s warehouse. but even then its more a gradual thing due to the sizes of these places so not a hot/cold scenario just like as quick as I said.

    it’s not a good thing to happen regardless and it’s not supposed to happen. It is really annoying when it does! I’ve been there and have several T-shirts 🙄

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