Ball

CDI or High Definition, single or double pass, spot colours instead of CMYK.

Learn how to optimise your design for the can print process.

generic design & screen
guidelines

Interact here
a guide to printing plates

Take a look
hints and tips...

Interact here

AGuideToPrintingPlates

A guide to printing plates

Plate

Conventional printing plate
Screen 2% to 10%

CDI printing plate
Screen 2% to 10%

Laser printing plate
Screen 2% to 10%

Conv.
plates

CDI
plates

Laser
plates

Print

Conventional Print
Dot growth approx. 25 - 30%

CDI Print
Dot growth approx. 20 - 25%

Laser Print
Dot growth approx. 15 - 20%

A conventional printing plate is made by exposing a negative film onto the polymer of a steel backed plate using UV light. After the exposure, the plate is washed to remove the excess polymer.

A plate made using the Computer Ditigal Imaging technique receives the image directly from a computer file which is printed by a laser directly to the film attached to the plate. After short exposure under UV light, the excess polymer is washed off.

The detail is engraved directly on the printing plate by a high precision laser.
HintAndTips

Hints
&
Tips

1

Are you looking to achieve the effect of a total fade out of your screen?

2

Are you looking for ideas to hide the "hard line" which a fading vignette leaves on a can?

3

Is your priority to achieve a consistent image on your design?

4

Are you looking for a subtle pattern in the background of your design?

5

Would you like to create the perfect overlap on an aluminium background?

6

Do you like to create an illusion of fading colours towards the middle of your design?
HintAndTips1

Hints & Tips no.1

Reproduced
design element

Production
can

Fine screen

Course screen

Consider the use of a course screen instead of a very fine screen.
This often gives the illusion of fading to zero.
HintAndTips2

Hints & Tips no.2

Customer supplied artwork showing a clean and smooth
purple to blue transition

Reproduced design,
ready for can production

Printed result on a can, where dots have gained
leaving a hard edge where the vignette is stopped

Consider to use another design element such as a line of text,
a line of another colour in the design or for example the neck
line(point where the neck shape starts on a can)
to hide the hard edge of the vignette.
HintAndTips3

Hints & Tips no.3

Consider to use only one strong facing illustration on your design.
Use the back of pack for your ingredients list or a different image.
By creating your design in this way, you don’t risk any side to side
variation (inherent to our process) on the images on your design.
HintAndTips4

Hints & Tips no.4

Single print

Screen print

Instead of using a screen to create a subtle background pattern,
consider to print the background with a double pass and the pattern with just a single pass of the background colour.
This will guarantee a consistent subtle pattern in the background.
HintAndTips5

Hints & Tips no.5

Visible overlap

Visible overlap

Invisible overlap

Consider to leave the overlap free of any design element. Plan a gap in your design
in the position where the design overlaps, this way you don't notice the overlap at all.
HintAndTips6

Hints & Tips no.6

Instead of using dots for your vignette, consider the use of cone shaped lines.
This method can help create the optical illusion of colours fading to zero
without leaving the hard edge in the middle which appears with a normal vignette.

High Definition – spot colours

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Generic design guidelines

Screen guidelines

HD Screen guidelines

HD printing uses special colours – not CMYK. A CMYK image will be separated into special colours during reproduction. Because the screen ruling for HD printing is higher a representation of an image will be closer to the original, but still will not match it exactly.
High Definition – colour separation

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Avoid using colours which are needed in an image (a), elsewhere on the can (b). This will allow Ball to best control these colours used in the image in production.
High Definition – screen ruling

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Generic design guidelines

Screen guidelines

HD Screen guidelines

The maximum screen ruling for HD printing in can design is 120 LPI. Ball will decide during the reproduction process based on all elements in the design, which screen ruling gives the best final result in production.
High Definition – Dot size

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Generic design guidelines

Screen guidelines

HD Screen guidelines

The minimum dot is 2%.
High Definition – Dot gain

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Generic design guidelines

Screen guidelines

HD Screen guidelines

In High Definition print the expected dot gain in production is between 10 – 15%.
High Definition – Vignettes

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Fading to 0 under circumstances is possible, although leaving an even soft edge over a big area of the can does not belong to the possibilities (dots will not consistently hold on the plate).
High Definition – Image illusion

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Generic design guidelines

Screen guidelines

HD Screen guidelines

It is possible to create an optical illusion of a third colour by partly overlapping screens. This will only be applied to screens and in order to get the best possible end result, it will have to be done by a Ball qualified specialised reproduction studio.
Spot colours

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Can printing uses spot colours – not CMYK. An image using CMYK colours is separated into spot colours during reproduction. The aim is to give a close representation of the original, but it will never match it exactly.
Screen ruling

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Generic design guidelines

Screen guidelines

HD Screen guidelines
The maximum screen ruling for can design is:
85 LPI in Conventional printing
100 LPI in CDI printing
120 LPI in HD printing
Ball will decide during the reproduction process and based on availability which screen ruling is going to be used.
Dot size

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Generic design guidelines

Screen guidelines

HD Screen guidelines

The minimum dot which a dry offset letterpress plate can contain consistently is 3%
Dot gain

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Dot gain in our process may be as much as 20 - 30%
Vignettes – hard line stop

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Generic design guidelines

Screen guidelines

HD Screen guidelines

A screen should continue over the entire surface of the can, fading a colour to zero and leaving a soft edge is not possible due to the dot gain experienced in the can printing process.
Wet - on - wet – screens

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Avoid printing colours wet-on-wet as much as possible. Due to the nature of the printing process we have limited control over the final result. Colour variation in batches can be expected. Wet-on-wet printing can only be considered with complimentary colours, screen size & angels. Contact Ball in a very early stage of the development process, so we can help you achieve the best result.
Wet - on - wet – solid

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Generic design guidelines

Screen guidelines

HD Screen guidelines

It is not possible to create a third colour using two colours printed on top of eachother. The consistency of this colour cannot be guaranteeed throughout the production. It results in contamination of the colours in other areas of the design.
General overview

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Generic design guidelines

Screen guidelines

HD Screen guidelines

The process used to print cans is called “Dry-offset letterpress”. This means that a printing plate is used for each colour to print that part of the image to a blanket. One common blanket collects all the different colours, until the full mirror image of the design is complete (1 rotation of the blanket). The blanket transfers all the colours at once to the can – see also print processes for more details. Maximum resolution used in can printing is 120 LPI. During the reproduction process the customer supplied artwork is separated into spot colours and the relevant screen ruling applied. We also introduce “air gaps” to protect the design against colour contamination during printing. This process can only be carried out by a Ball qualified reproduction studio.
Vignettes – direction

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Vignettes should always run from top to bottom (vertical) with a maximum of two colours opposing.

Horizontal vignettes running around the can should be avoided. Due to the nature of the process small differences in pressure at print stage and the lack of controls of ink in the print direction make it impossible to control the printed end result.
Colour separation – large area of colour

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Generic design guidelines

Screen guidelines

HD Screen guidelines

A large surface covering the same colour has to be split over 2 printing plates
Colour separation – text & block of colour

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Fine text and an area of the same solid colour has to be split over 2 printing plates
Colour separation – screen & solid

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Solid colour & screen in the same colour has to be split over 2 printing plates
Distortion

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Generic design guidelines

Screen guidelines

HD Screen guidelines

The neck of the can is formed after printing and therefore any image in this area will be distorted.
Overlap

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Because a can is cylindrical, your design will overlap on itself by approximately 2 mm. Point-to-point contact in the overlap differs by production line & size. Perfect alignment can therefore not be guaranteed in the overlap.
We recommend to keep the overlap free of any continous graphics and text. An ideal overlap has the same solid colour on either side of the design.
Line thickness

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Generic design guidelines

Screen guidelines

HD Screen guidelines

Minimum line thickness:

- Positive lines 0.1 mm
- Negative lines 0.25 mm

AirGaps

Air Gaps (reversed trapping)

Artwork with air gaps

Printed result on can

To protect the colours on your design from contaminating, Rexam adds small gaps between all design elements in different colours during the reproduction process. The size of the gap depends on the colour and the size of the elements in this colour. Air gaps disappear as they typically fill up with ink as this spreads during production. They are calculated to suit each of our plants to protect the colours on your design from mixing.
As these gaps are specific to our process they can only be added by a Rexam qualified reproduction studio.

generic design & screen guidelines

a guide to printing plates

hints and tips...

A guide to printing plates

Plate

Print

Hints& Tips

1

2

3

4

5

6

Hints & Tips no.1

Reproduceddesign element

Productioncan

Fine screen

Course screen

Hints & Tips no.2

Hints & Tips no.3

Hints & Tips no.4

Hints & Tips no.5

Hints & Tips no.6

High Definition – spot colours

High Definition – colour separation

High Definition – screen ruling

High Definition – Dot size

High Definition – Dot gain

High Definition – Vignettes

High Definition – Image illusion

Spot colours

Screen ruling

Dot size

Dot gain

Vignettes – hard line stop

Wet - on - wet – screens

Wet - on - wet – solid

General overview

Vignettes – direction

Colour separation – large area of colour

Colour separation – text & block of colour

Colour separation – screen & solid

Distortion

Overlap

Line thickness

Air Gaps (reversed trapping)

Design, Image & Illustrations

generic design & screen
guidelines

Hints
&
Tips

Reproduced
design element

Production
can