Technical requirements for design and files

Correct print preparation is of the greatest importance in obtaining a high-quality print. In the case of insufficient preparation, it is not possible to significantly improve the result during printing. We can only guarantee you the best quality if you follow the instructions given in the instructions. If you have questions or problems, we are ready to help and guide you.

Technical requirements for design

Bleed in case of adhesive binding

In addition to the final size of magazine there must be added 5 mm of bleed area on each side. The bleed areas must be symmetrical and the page layout design must be placed in the middle of the page.  See more: instructions.

Bleed in case of wire binding

In addition to the final size of magazine there must be added 5 mm of bleed (at least) on three outside edges. 

Spread pictures in an adhesive-bound magazine extending over two pages

The perfect bound magazines are made with a technique called hinge binding covers. This requires 5 mm side glue on the front and back covers and is used to hold the magazine together more securely. When designing double-page advertisement between an inside cover and it’s facing page (aka “crossover”), both pages should be moved toward the face trim by 5-7 mm to achieve a correct continuous picture extending from the inside of the cover to the first content page, because bounding makes “crossover” pages shorter by hiding 5-7 mm of image under the glue. See more: instructions.

The placing of design elements

Texts and other critical design elements (borders, lines etc) must be placed at least 4 mm from the trim box. See more: instructions.

Online-adhesive magazines

In the design it must be taken into account that the middle strip of adhesive which connects the pages covers about 1 mm of both pages (the width of the glue strip is 2 mm). There is no need for a white line. Texts and other critical design elements (borders, lines etc) must be placed at least 4 mm from the trim box.
20-, 28-, 40- and 56-page signatures are printed using folding-scheme, where some sheets are not double (4-page), but are single (2-page) sheets and have glue strip covering area with width up to 10 mm on inner side. On particular area images and design elements have to be avoided: 10 mm of safety area has to be used. Safety area is necessary on following pages with narrower printing area:
a) 20 page signature: pages 12-13; 16-17
b) 28 page signature: pages 19-22
c) 40 page signature: pages 21-22; 27-30; 35-36
d) 56 page signature: pages 31-32; 39-42; 49-50

Overprint

Colored and white objects (except 100% black) must not have a defined overprint mode.
In order to avoid visible effects of misregistration in the case of black text on a colored background, overprint should be defined to all black (100% K) objects printed on coloured backgrounds.
Avoid using solid black (100% K) for large objects over other objects – rich black (C:40, M:30, K:100) or black without overprint (CMY:1, K:100) should be used instead (e.g. the black frame covering the edge of a picture). Black overprint is added automatically at a printing house to improve printing quality.
If overprint of non-black objects has been used or if there are other special requirements, you should inform repro in each particular case.

Trapping of objects

When objects of different colour come into contact during design, the edge of the darker object should cover the edge of the lighter object by 0.1 – 0.4 mm (aka “trapping”). For the white text on dark background (aka reverse or negative text) the background color should recommendedly be solid 100% black or classical rich-black (CMY:50:40:40 and K:100%). In these conditions white trapping (a.k.a. keep-away trapping) is added automatically at the printing house to improve printing quality. Additionally, for the sake of quality, add the outline (stroke) under the white text with the color of non-overprinting black (CMY:1% K:100%) with stroke size of 0.25 pt. Trapping is added automatically at a printing house to improve printing quality.

Line-art

The minimum width in case of line-art has to be at least 0.15 mm. Line-art should contain no more than two overprinted colours.

Texts

Avoid using small 8 point or smaller texts (or text height less than 2 mm, or minimum line width less than 0.2 mm) reverse (white) type in coloured objects (knock out). The minimum size of oblique or sheriff type in coloured objects should be 10 points. Avoid placing reverse (white) type into screened areas lighter than 50% or into yellow background to ensure readability and contrast. Avoid using small 8 point or smaller texts (or text height less than 2 mm, or minimum line width less than 0.2 mm) reverse (white) type in coloured objects (knock out). The minimum size of oblique or sheriff type in coloured objects should be 10 points. Avoid placing reverse (white) type into screened areas lighter than 50% or into yellow background to ensure readability and contrast.

Pictures with pure tone

In order to achieve the best printing quality, the cleanness and brightness of the coloured images should be improved by removing “contaminating colours” from the images. To get clean colours, it is advisable to remove yellow from the blue colours, magenta from the green, cyan from the yellow, etc., without sacrificing image details.

Colour space of all pictures and vector objects – heatset printing

All colour pictures and colours used in design should be in CMYK format.
All used spot colours should be converted to CMYK. All non-CMYK colours: Pantone tones, RGB, Lab etc will be automatically converted to CMYK format by colour profile od printing paper, but sometimes the result can be undesirable.

Colour space of all pictures and vector objects – covers, inserts, etc in sheed-fed printing

CMYK + Pantone tone(s) specified in the written order. Other Pantone tones, RGB, Lab etc are automatically converted to CMYK which may remarkably distort the tones requested by the client.
Use Spot color guide for choosing spot color: see the guide.
Use this Pantone spot guide for choosing CMYK values: see the guide.

Postpress recommendations

Colours

In case of pictures it is ensured by the use of the right ICC profile, in case of vector graphics the fulfilment of the requirement must be ensured by the designer. Using silk papers in production, smearing can still occur if pages containing images with total area coverage close to, but less than maximum limit are placed face-to-face with pages having a lot of white area. Check the colour separation requirements: see papers and profiles.

Metallic and florescent (neon) colours

If using PMS metallic (Pantone 871) or florescent colours (Pantone 801) in the design, there should be know that these inks are not transparent but opaque and will be printed as last inks. In case of designing of black texts on top of objects of metallic or neon colours, the non-overprinting black colour of CMY:1%, K:100% should be used. If usual black colour of only 100% K is used, then black ink is covered with opaque spot-colour and the black object will not be visible.

The use of black colour

In the design the use of 4-colour black (rich black) must be avoided in case of small black texts and line objects. For small black texts use only black ink colour (100% K). In case of large black areas 4-colour black (for example C:40, M:30, K:100) must be used. The colour All (or Registration) is not reccommended and will be converted automatically to only black ink colour (100% K).

Black-and-white vector objects

Black-and-white vector objects must not contain CMYK or RGB color tones.

The limits for the reproduction of an integrated and uniform screen (i.e tone values) on a paper

Tone value reproduction limits are 3%-97%. No significant image parts shall rely on tone values outside of the above tone value reproduction limits.

Maximum summarized raster percent (TIL – total ink limit)

Depends on paper type, check the colour separation requirements: see papers and profiles.
In case of pictures it is ensured by the use of the right ICC profile, in case of vector graphics the fulfilment of the requirement must be ensured by the designer. Using silk papers in production, smearing can still occur if pages containing images with total area coverage close to, but less than maximum limit are placed face-to-face with pages having a lot of white area.

Resolution power of the pictures in design (dpi)

Check the colour separation requirements: see papers and profiles. The smaller decreases the quality of pictures, the bigger does not improve the quality, but increases the size of the files and makes their processing slower.

A digital increase of the resolution of low resolution pictures to the required level

Kroonpress considers such transformation a deliberate activity by the designer. The automatic inspection of the files will not detect it.

Continuous and broken perforation

Perforation line must not be drawn in the design, but if necessary, it must be designed with spot colour (e.g. Perforation) and it must be defined to overprint. The typical distance of the perforation line of a coupon from the inside gutter is 15 mm.
Continuous perforation runs in a straight and unbroken line from one page edge to the other and is performed with the perforation wheel-knife of the folding machine.
Broken and special perforation is performed with die-cut form. Cardboard is also perforated with a die-cut form. In case of die-cut a special form should be prepared and the whole process may take longer.

Die-cut line

Die-cut line must be designed with spot color (e.g. Die-Cut or Perforation) and it must be defined to overprint. Special die-cut forms must be designed with different colors: knife = red line, grease = green line, perforation = yellow line. There should be avoided double lines and dotted lines.

Numbers, barcodes

Barcode should be precisely readable, therefore the EPS file format is the best (because no blurry edges) but TIF format is also suitable when the image resolution is high (300 dpi) and edges are contrasted.
Barcode should be designed for the sake of readability with 100% of black color in vector graphics.

Folio design

Folio must be designed as monochrome (only black and white) objects with spot colour (e.g. Folio) and it must be defined to overprint. Folio will be added on top of background image without white knockout holes. The thin line with folio or (knockout) line in the folio background should be at least 0.3 mm width (recommended width 0.5 mm). Colour object on folio background (like colour knockout text) must have 0.25 mm trapping (e.g. text should be extended with overprinted outline). The correctness of positioning of folio is 1 mm, therefore avoid thinner than 3 mm lines (outlines) around the folio object. Folio will be added with hot glue and pressure, therefore the pressure marks can be slightly visible on the opposite side of paper.

Scratchable element

The silver scratch-off (lottery ticket) design element must be designed with a spot color (e.g. Scratch off) and be overprinted. The element to be scratched is applied to the paper using the serigraphic method.

Spot UV varnish & Drip-Off

Spot UV varnish object must be designed together with CMYK layout with spot colour (e.g. SpotUV) and it must be defined to overprint. The minimum width of lines or knockout (holes) of objects has to be at least 1 mm. CMYK layout and spot objects should be on the same page on different layers. Use PDF/X-4 for layered-PDF.

Drip-Off represents an efficient and eye-catching method to achieve matte/gloss effects or matte/structure effects in a single process with just one coating unit.
The principle: in the last ink duct, a primer is partially used. Out of the coating unit, a high gloss coating is applied on whole area. Where primer and high gloss coating meet, a repellent effect is realized, resulting in matte structured area, which is called “Drip-Off”. Where the primer has been left out, high gloss surface is obtained. In this way, you can produce fine printing motives without a spot coating plate.
It is also possible to use raster (min 50 %) for primer layer in order to obtain unique Drip-Off structures.

Drip-Off workflow in printing machine:
1) Offset release varnish/primer is applied in the last printing unit using offset printing plate
2) Offset release varnish/primer is cured
3) High gloss coating is applied on the whole area in the flexo coating unit
4) High gloss coating is cured

Drip-Off varnished (matte) area must be designed together with CMYK layout using spot color (e.g. Drip-Off) and it must be defined to overprint.

Effect of lacquers and laminate on color tones

It must be taken into account that UV varnish is yellowish and can distort background colour tones. Also mattee varnishes (and laminate) can decrease brightness and glossyness of colour tones.
When choosing additional spot colours, it must be taken into account that most varnishes in case of some specific Pantone inks, due to the chemical reaction, will dramatically change colour tone. For example Pantone Purple will turn to pink when covered with UV-varnish. The same happens with all inks containing Pantone Purple, Rhodamie Red, Violet, Reflex Blue, Blue 072, Warm Red and Red 032.

Print file requirements

File format

PDF-file, according to the standard PDF/X:1-a (2001). 

Unseparated PDF file

PDF files must be unseparated (composite).

One PDF-file page = one document page

Each PDF page must only contain one document page, i.e. 1-up single page. The reader’s spread layout is not recommended.

Cover files

The printed cover pages and spine could be designed in separate PDF files (five files in total). The front cover page and the spine could be in one PDF file, but on different pages. In the case of special solutions (flap, etc.), please contact with Sales Manager. Spine width can be calculated and value should be agreed also with Sales Manager.

The names of PDF-files

The name of the PDF file of every printed matter must include the page number(s) and the name of the job (e.g. 003_print.pdf – page 3 of printed matter called “Print”). The using of “_” (“underscore symbol”) as the separator of page number and job name is recommended. Note that the page number is on the first position.

Finality of the PDF-file

PDF files must be final, i.e. all digital advertisements and other elements should be already assembled on the layout sent to the printinghouse.

Design format

All submitted files should be in the final print size, i.e. 1:1 compared to the final product.

Technical marking

We recommend for all files submitted for printing and imposition not to use the technical markings, i.e. crop marks, colour identification, file infotext or registration marks. If the crop marks are used (and also marks designating the perforation line) in the bleed area, there should be take care that these marks must not be closer than 3 mm to the clean publication format (TrimBox).

Fonts

All fonts used in design must be included in the PDF files submitted to the printing house.

The changing of files

If the client makes amendments to the files sent to Kroonpress, he/she must immediately notify the prepress department or the sales manager. Otherwise Kroonpress will not guarantee that the amendments will be printed.

The confirming of softproofs

Softproofs must be confirmed in writing (using for example an e-mail). In Apogee Portal system the softproof confirming is system-based.

Contract proof requirements

Kroonpress does not accept the print samples of other printers or other colour prints that do not comply with the requirements of ISO12647-7. Kroonpress produces and accepts only the contract proofs of the client which accepts on the following conditions:

  • The same proper ICC color profile has been used in preparing contract proofs which conforms to the printing paper used
  • It is possible to verify the accuracy of the colour tones on the contract proof:
    • Each contract proof has a color strip conforming to the requirements of ISO12647-7, for example UGRA/FOGRA Medienkeil
    • In case of other control strip the respective CMYK values must be added to the measurement field
    • The name of ICC color profile must be marked to each contract proof
    • If a non-standard ICC profile is used, it must also be delivered to Kroonpress
  • The results of the verification of contract proof conforms to ISO 12647-7 requirements

Responsibility

Kroonpress is entitled to reject the material sent by the client which does not conform to the technical requirements and demand the submission of material which conforms to the technical requirements.
To ensure printing quality Kroonpress is entitled to make the following unavoidable printing changes to the client’s files:

  • The adding of overprint to black ink (100% K)
  • The adding of trapping to the contour of objects of different colour
  • A decrease in the maximum summarised raster percent (total ink limit) to the amount suitable for the printing paper
  • Conversion of RGB and Pantone tones to the CMYK colour space (except if the client has ordered Pantone additional colour)
  • Adjustment of page technical markings (crop marks etc) in case these are againts the present technical requirements

The customer shall bear the costs of remaking the material submitted by the customer that does not meet the technical requirements at Kroonpress, as well as the additional costs incurred in the printing house due to the material that does not meet the technical requirements.

Recommended colour profiles

Here our recommendations of color separation profile by paper type: see papers and profiles.

You can also use the checklist as an aid before creating the final print files: see the checklist.

PDF Upload and Page Approval system

Apogee WebApproval allows you high flexibility in delivering files to us and checking your pages. You’ll have the ability to review, approve, reject and annotate your pages online, 24/7. Enter the web portal Apogee WebApproval and log in with your email and password. If you have forgotten your password, then click on “Forgot your password?” and follow instructions.

Here’s a brief overview of how the process works:

  • Log in and create the new job in our self service portal. We can also create a digital job for you: send us necessary information and you will be notified via email when the job is available for you.
  • Start the uploading of your documents.
  • After the upload of pages, you can assign them to the pages, in the desired order.
  • The system then starts preflighting and processing your documents into online digital proofs.
  • When processing is ready, the system will send you an email.
  • Log in again and review your pages or download the usual Softproof PDF and review.
  • If everything is correct, approve the files.
  • Otherwise, reject the pages, upload your replacement documents and repeat the approval process.

Apogee WebApproval

File upload and page handling

Apogee WebApproval

Remote proofing and page approval

Environmental certificates – logos

If the printed product meets the criteria, our customers can use the Nordic Swan Ecolabel and PEFC labels on their products. To do this, please inform our sales department and indicate the use of the desired logo in the order letter for the product. After confirmation, we can book the suitable and certified paper.

Clicking on the images opens a file in PDF format. Please contact the sales department for detailed logo usage instructions.