Unit 6 - Working with Paper Flashcards
(22 cards)
Categories of paper
A series - standard stock sizes
B series - alternative sizes
C series - used for envelopes
RA - 105% of A series
SAR - 115% of A series
5 qualities of paper
Strength absorbency
Finish
Whiteness
opacity
Cost
6 stages of creating paper
- Begins with debarked and chipped wood
- Acetic acid is used to break down the fibres
- Fillers (clay or calcium carbonate) are added
- Bleach is added to brighten the mixture
- Large volumes of water are added
- The mixture is heated to 140°C to produce a pulp
- At least 500ml of water is used for each A4 sheet, however much of this water can be recycled
2 paper coatings and purposes
Coatings can be added to reduce ink absorption and prevent bleeding
Clay - helps to improve smoothness
Polyethylene (PE) - increases gloss and improves wet strength
4 types of finishes
Matte - smooth and dull, often used for printing
Satin - between matte and gloss, often used for photography or wedding invitations
Gloss - shiny, high quality, often used for photography
Textures - can be added with a foam and wire roller to produce patterns
Cutting paper in the workshop
- Steel safety rule
- cutting mat
- scalpel for cutting
- blunt edge knife for scoring
What 3 materials can paper be made from?
- Debarked and chipped wood
- Cellulose fibres from plants
- Bagasse ( shredded waste sugar cane)
How is paper classified?
By weight and size
GSM (grams per square metre)
Microns (1000 microns = 1m)
Anything over 220 gsm is considered a board
Which organisations regulate paper and board?
Forest Stewardship Council (FSC)
Programme for the Endorsement of Forest Certification (PEFC)
Screen printing
Uses - T-Shirts, Tote bags and Posters
Benefits - low set-up cost and can be used with a variety of materials
Key terms - squeegee, photo emulsion
Process
- A fine mesh screen is coated with a photo emulsion
- Light is used to fix the photo emulsion into the desired shape, and excess is washed away
- Ink is applied to the screen and spread across using a squeegee
- Ink fills in the desired shapes and is left to dry
Flexographic printing
Uses - variety of substrates
Benefits - cheap, efficient and high volume
Key terms - anilox roller, doctor blade
Process
- Ink is collected from the reservoir
- Tiny cells in the anilox roller collect the ink
- A doctor blade determines how much ink is needed
- The printing substrate is held between the impression cylinder and the printing plate cylinder
Offset lithographic printing
Uses - magazines and catalogues
Benefits - low unit cost, quick, high quality
Key terms - Oleophilic, Hydrophilic, impression cylinder
Process
- The layers of colour are separated
- Each layer etches an aluminium printing sheet, and the plate is then treated with oleophilic and hydrophilic areas
- The oil-based ink is repelled by the hydrophilic areas and is attracted to the oleophilic image areas
Machine
- The printing plate is attached to the cylinder
- Oil and water are added
- The ink is then offset onto a smooth cylinder
- The printing is completed when the paper is passed through the offset cylinder and lower impression cylinder
Types of digital printing
process
files are sent to the printer
can be done on a variety of substrates
types - Ink Jet, Laser printing
Ink Jet printing
- The printer is loaded with ink cartridges
- The printer head passes over the substrate and squeezes out the ink
Laser printing
- Drums separate each colour (CMYK)
- The drums are positively charged
- A negatively charged laser charges certain areas
- The toner powder sticks to the negatively charged areas
- a transfer belt picks up the toner and deposits its onto the substrate
Embossing and debossing
Embossing - creates a raised indent
Debossing - creates a lowered indent
Uses - texture and braille
Process
- the material is placed between two heated plates
- the plates shift the papers fibres without tearing
- the design has been indented
- if done without ink, it is known as ‘blind embossing’
Foil blocking
Uses - decorative process to add metallic features
Process
- A heated metal die stamps foil onto the material
- It attaches to the substrate through heat and pressure
- can be done with flatbed or rotary dies
Lamination
Uses - protective finish
Process
- a laminate film is applied to both sides of the substrate
- available in matt, gloss and satin
Encapsulation
a form of lamination using a laminator
- the laminate is sealed using heat and pressure
- plastic fuses to the paper
- quick and simple, but limited materials and sizes
3 types of Varnishing
Uses - protective barrier
Process
- a liquid varnish is applied
- Water-based varnishes dry quickly and are more eco-friendly;
- Solvent-based varnishes are half the price but more toxic
- Specialist UV varnish cures under UV light – this varnish is so glossy it’s often mistaken for a lamination
Plotter cutting
A machine head holding a blade
or pen passes from left to right
Simultaneously, rollers move
the material back and forth
Plotters can incorporate printing
functions so graphics can be printed,
cut and scored at the same time
Often used with self-adhesive vinyl
to create signage and vehicles decals
Die Cutting
A die is used to cut through thin material
such as fabric, paper or vinyl to produce repeating patterns
