Creasing digital laminated book covers

[Stickman42]

We've been printing our covers on 10 pt. C1S on Xeroxes for a while now. The film laminated ones - we experience the adhesion difficulties that all similar users do. Through adjustments of laminating temp, pressure, speed, etc... we do the best we can. However, when we use matte film lam, we have the most difficulty with getting adequate adhesion. I've spoken with the manufacturer (D&K) and they related that the matte base material is more difficult to transfer heat through than the gloss film base material. This compounds our trouble.

Most recently, we perfect bound a book with dark print on the cover in the spine and hinge score area, and matte film lam. The spine and hinge (rotary) scores were made inline on the binder (Horizon BQ470) as the covers were fed. We saw very slight "bubbling" of the film lam in the hinge score area immediately after the bound books were coming off the binder last Saturday. When we got in on Monday, the "bubbling" was much worse. I'm fairly certain the adhesion was barely adequate, and the combination of the rotary scoring and time allowed the film to release from the cover sheets.

My question - has anyone who has had a similar experience tried creasing this type of cover on a Duplo or Morgana and had any improvement in the finished product?

 

[pippip]

Is your laminating film standard? We order in Ultrabond film, matt and gloss. Its a super adhesive film specifically for digital prints. We use a morgana digicreaser and have had similar issues.

I haven't tried got round to proper testing but I did wonder before if the grain direction could make a difference as it should give a smoother fold on the crease.

 

[Puch]

Some of our customers order batches of books without creasing, just because of the bubbling you described. This way the glue has more time to stick, and the bubbles appear only when the reader opens the books first time. I agree, this is very far from a perfect business model. The other way is to play around with the available laminate materials, and select the most pleasant one. We asked the printer's vendor about it, since they have a lot of info from their customers.

With very demanding jobs we don't use the perfect binder's crease option, but crease the opener lines with an off-line machine, which is a not a rotary, but press creaser.

 

[Stickman42]

Is your laminating film standard? We order in Ultrabond film, matt and gloss. Its a super adhesive film specifically for digital prints. We use a morgana digicreaser and have had similar issues.

I haven't tried got round to proper testing but I did wonder before if the grain direction could make a difference as it should give a smoother fold on the crease.

We use D&K SuperStik film. It's Xerox approved. We also use stock with the grain parallel to the spine. AND we lower the total ink coverage when necessary to no more than 240%.

 

[Stickman42]

With very demanding jobs we don't use the perfect binder's crease option, but crease the opener lines with an off-line machine, which is a not a rotary, but press creaser.

Have you experienced improved results by creasing offline? I'm contemplating purchasing a creaser/folder for other types of work, but would be very happy if it helps my perfect bind bubbling issue as well.

 

[KopyBoss]

My question - has anyone who has had a similar experience tried creasing this type of cover on a Duplo or Morgana and had any improvement in the finished product?

We crease laminated covers printed on the Xerox 1000 using the Morgana, works great.

 

[lfelton]

Creasing vs rotary scoring is probably not your major issue here, the bond between the adhesive and toner probably is. There are a lot of variables here, what machine are you printing on, what laminator are you using, what pressure have you set the rollers to, how fast are you running the laminator etc. I can give you a couple of pointers, but really you need to work with D&K to get to the bottom of this (I've found them very helpful, at least here in the UK).

Pointers.

You mention matt as your worst case. Matt superstick has a very narrow temperature window that it adheres well within. Gloss is MUCH wider and so you can get away with just about anything with gloss. Are your heaters in good condition? Don't believe the laminator's read out! Get a calibrated contact thermometer (infra red won't work for the obvious reason) and take readings across the width of your heated roller. Too hot and you will get bubbling and film distortion. Too cold and you'll get poor adhesion (silvering, lifting). Your laminator needs to be bang on, all the time.

Next, speed. In general, superstick will stick to just about anything if the temperature is correct and you run the laminator slow enough. If you run the laminator faster than your heater's capacity to keep the temperature constant, you are going to get poor adhesion.

There is a LOT more to consider, but hopefully that might help get you going.

 

[Stickman42]

lfelton - thanks for the detailed explanation. It is as I feared it would be. But I love a challenge...

We are running an (older) D&K 27" laminator, and their film, so I think I should be able to find someone willing to take on my case. Getting the thermometer is no problem. Getting my operator to be more in tune with things is going to prove more difficult.

 

[dabob]

Get a calibrated contact thermometer (infra red won't work for the obvious reason)

just an apparently dumb question . . why wouldn't an infa red temp work???? We have used ours to measure the temps on a racing tire to be sure its even all the way across . . . why wouldn't it work on a laminator. (I haven't run a laminator for 30 years so excuse my ignorance)

 

[Stickman42]

just an apparently dumb question . . why wouldn't an infa red temp work???? We have used ours to measure the temps on a racing tire to be sure its even all the way across . . . why wouldn't it work on a laminator. (I haven't run a laminator for 30 years so excuse my ignorance)

The only dumb question... IR thermometers are not accurate when aimed at a reflective surface, like a chrome heat roller.