Allied Bindery

Bound for Excellence

High Profile, High Use – PUR is the Only Choice

Polyurethane Reactive (PUR) adhesive has become the adhesive of choice for many printers and trade binderies during the past several years.  It has been particularly popular when matched with coated stock projects.  One of the most common questions that is posed to us is “When does it make sense to use PUR?”

Allied Bindery was an industry leader for the introduction of PUR and we have experienced a significant growth in the use of PUR during the past several years.  We recommend that the following attributes be used as a guideline for choosing PUR for your binding projects:

Coated Stock – particularly 70# basis weight and greater.  The heavier the basis weight of the stock, the more stress that is placed on the glue line when pages are flexed (turned) by the end user.

  • Cross Grain Stocks – whether coated or uncoated.  A short grain stock simply does not have the fiber exposure and fiber length to create a strong page pull or flex result when paired with an Ethyl Vinyl Acetate (EVA) adhesive.
  • Mixed Stocks – PUR is the superior choice when a project utilizes mixed text stocks with a variety of fiber characteristics.
  • Synthetic Stocks – With no fiber available, an EVA will quickly fail.  PUR adheres via a chemical melding versus a “mechanical” glue bind.  PUR is the best choice for synthetic stocks.
  • Full Ink Coverage – In general, inks and most coatings will not repel PUR as they will EVA adhesives.  If your project includes a full ink or coating coverage into the spine grind area, consult with your Allied Bindery representative so that we can guide you with respect to knock outs.
  • High Use Products – Catalogs, Directories and Text Books are examples of products subject to a high usage rate, which must also stand the test of time.  PUR provides vastly superior page pull and flex results that allow for a high usage rate without the spine breaking down.
  • Extreme Heat or Cold – EVA adhesives will cold crack at just less than 40 degrees Fahrenheit and re-soften at 120 degrees Fahrenheit.  If you have products that will be stored or used in extreme cold or hot climate conditions, PUR provides superior results.

Cross Grain Covers – Are You Saving Money or Creating a Headache?

Depending upon the final trim size of a binding project and the sheet size capacity of the printing press, printers often make decisions to use a cross grain sheet when printing covers for a stitching or binding project.  Although this decision may save on the cost of paper, it may also create several cosmetic or functional issues that may lead to additional downstream costs.  Several things should be considered before deciding to print a cross grain cover.

Spine and Hinge Score cracking is a common complaint when cross grain covers are used.  If the cover design requires full ink or dark ink coverage, cracking along the spine or hinge score becomes highly visible and can be viewed as an objectionable cosmetic defect by the customer.  The best opportunity to minimize this type of problem is to die score the spine and hinge score areas of the cover.  A die score is a superior choice to the wheel score that may be provided by a perfect binder or saddle stitcher cover feeder.  The die score, however, increases the cost of the project and may offset any savings generated by the use of a cross grain sheet.  Additionally, if the requirement to die score is not identified until after the cover has been shipped to the Bindery, both the additional cost and additional processing time will be unexpected.

Cross grained covers applied to a perfect bound book will likely result in a series of waves along the length of the spine.  Once the cover is adhered to the body of the book, any moisture that may be absorbed by the cover stock can expand the paper grain.  Since the cover will be held in place by adhesive along the spine, waviness will often be created as relative humidity is absorbed into the cover stock.  Although the book remains functional, this cosmetic imperfection may leave a customer dissatisfied with the end result.

Involving the Sales and Planning Professionals at Allied Bindery can help you avoid problems such as recognizing or avoiding potential problems with cross grain covers.  Give us a call and let us help you achieve your customer’s expectations.

To Stick or Not to Stick – UV Coating versus Binding Adhesives

Incorporating UV Coating into perfect bound print projects is a great opportunity to enhance the visual and cosmetic characteristics of a printed piece.  Understanding interaction between UV Coating and binding adhesives will help printers avoid unpleasant surprises in the finished product.

A key ingredient in the chemical make up of UV Coating is silicone.  Silicone provides a degree of “slippery-ness” in the coating.  The amount of silicone in UV can have a dramatic impact on the ability of the binding adhesive to stick to or repel from the UV coated material.  Depending upon the amount of silicone used in the chemical make up of the UV Coating, adhesion problems may result.   In other words, more silicone equals more binding related challenges.  Since the bindery will not have any knowledge as to the silicone content in UV coated materials, problems will likely not be identified until the binding process is underway or complete.

Binding adhesion problems with UV coating may appear in a number of different ways.  If the UV coating is a flood coat extending into the spine grind area and the UV coating contains a high level of silicone, there may be total adhesion failure at the spine.  The silicone content will repel the binding adhesive and not allow a stable or consistent adherence between text paper stock, the spine adhesive and the book cover.

A UV coating with a lower level of silicone content may allow for adequate adhesive strength, but may allow for adhesive migration up between text pages.  Adhesive that migrates as little as 1/16” up from the spine will result in paper fibers tearing between pages as the book is opened.  Although the binding strength is adequate, the cosmetic result is poor and will be unacceptable to the customer.

When planning for a page or pages utilizing flood UV coating in a perfect bound book, make sure to knock out the spine grind area.  Eliminating the UV coating in the spine grind area will help insure an appropriate binding strength, while eliminating the potential for adhesive migration between pages, thus ensuring the quality level that you and your customer desire.

Involving the Sales and Planning Professionals at Allied Bindery can help you avoid problems such as recognizing or avoiding potential production challenges with UV Coating.  Give us a call and let us help you achieve your customer’s expectations.

Spine Perforations – Great Advantage or Wasted Effort?

Printers often incorporate spine perforations into the printed signature, whether folding a sheetfed form or delivering directly from a web press.  The perforation provides a distinct advantage to the folding process.  A spine perforation allows air to escape during the folding process, reducing the chances of wrinkling, bottling or shingling.  This, in turn, results in a better looking final product.

A significant risk that is often overlooked by a folder operator or web press operator is the size of the perforation blade or wheel.  If a perforation is too aggressive, i.e., lots of perf, not much paper remaining; the spine of the signature may break apart during the collation/gathering process at the bindery.

The amount of paper that is left intact on the spine provides the only strength to hold the spine together during the collation process.  The mechanical gathering process in the bindery requires that the spine of a signature be pulled down into the collator grippers using vacuum suckers.  If the perforation blade or wheel used at the folder or press was too aggressive, the paper will peel apart at the spine of the signature when the vacuum suckers begin to the pull the form into the grippers.

Once this happens, there is often no alternative other than to hand feed the affected signatures.  Hand feeding or hand collation results in increased expense and decreased production speed on the binder.  This is a phone call that the bindery does not want to make and the printer doesn’t want to receive.

A quick way to check the strength of the perforation is to flex and jog a handful of signatures at the folder or web press.  If the perforations show any indication of splitting or breaking apart during the hand jogging routine, they will break and fail during the mechanical collating process.  If this is noticed, it is time to change to a less aggressive perforation wheel or blade, thus helping to avoid unanticipated problems and additional charges during the binding process.

Spruce Up Your Perfect Bound Books with a Pocket Folder Cover

 

 Incorporating a pocket folder as the cover for your perfect bound project adds a visual pizzazz that can impress your customer.  Keep in mind that there are several key planning steps that must be considered to ensure that the pocket folder cover design is successful.

 A pocket folder cover project must be designed and prepared to allow for pre-binding of the text block, prior to inclusion of the cover.  The purpose of a pre-bind of the text is to allow the face and foot edge of the book block to be trimmed smooth prior to being aligned with the face and foot edge of the pocket folder. 

  Once the book block has been pre-trimmed at the face and foot edge, the book block can be combined with the pocket folder cover, using the foot edge as the primary collating guide.  The Binder Operator will then adjust the amount of spine grind to allow the face edge of the book to align with the face edge of the pocket folder.  Once the book block is glued into the pocket folder cover, a head trim is performed, resulting in text that is nearly perfectly fitted to the pocket folder cover.

 Remember, the face and foot edge of the pocket folder cannot be trimmed without destroying the pocket.  Fitting of the text to the pocket folder cover during two binding passes, as described, leaves the pocket folder intact, providing smoothly trimmed text and a pleasing product to your customer.

 Involving the Sales and Planning Professionals at Allied Bindery will help you avoid problems during the planning and design stages for pocket folder covers.  Give us a call and let us help you achieve your customer’s expectations 

 A core value of Allied Bindery is to communicate on an on-going basis with our industry friends.  Our objective is to share insight and observations considered valuable and helpful for our customers, helping you to provide an ever-increasing value proposition to your customers.                                        

Allied Bindery is a premier trade bindery located inMadison Heights,Michigan, celebrating 20 years of servicing your bindery requirements.