Credit Cards-Group 17 Updated

Post on 14-May-2017

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CREDIT CARDS

Overview

INTRODUCTION

History

Initially not made into a card

First issued around 1865

Initially made of celluloid

Later ones were made of copper, aluminium, steel or white

metal, which is when they became known as charge coins/

charge plates

Uses

Issued by banks that allow consumers to make

purchases on credit.

REQUIRED PROPERTIES OF MATERIAL

Durable

Recyclable

Economical efficiency – low-cost material

Weathering stability

Resistance to degradation

CURRENTLY…

Polyvinyl chloride (PVC), a thermo-plastic polymer.

Low price, recycling possible

High hardness and mechanical properties.

Highly versatile polymer

Limited thermal stability, decomposes at 140°C

PVC is also a durable material and is not affected by corrosion or other forms of degradation

PVC PROPERTIES

Mechanical properties enhanced with

stabilizers and additives

PVC materials are divided into two

classes: rigid and flexible PVC (pipes &

Tubes).

Credit cards are considered rigid PVC.

FLAMMABILITY AND THE OXYGEN INDEX

Oxygen index to measure flammability

Compound that is easily flammable will

burn with a smaller amount of oxygen,

hence it has a relatively low oxygen index.

CREDIT CARDS: OXYGEN INDEX OF PVC

Rigid PVC has an oxygen index of 45

Relatively less flammable than many other materials

The oxygen index for wood is around 20-25,

polyethylene or polypropylene also have lower

oxygen indexes (around 20)

BURNING CREDIT CARDS: POSSIBLE

DANGERS

Although PVC has a higher oxygen index, this does not

mean it cannot catch fire.

Gases formed when burning the credit cards can be quite

dangerous.

Addition of fire retardants to help increase the resistance

to fire

COMPARISON OF THE MATERIALS USED

TECHNOLOGY – INJECTION MOLDING

(COMPONENTS)

TECHNOLOGY – INJECTION MOLDING (CYCLE)

First

stage

TECHNOLOGY – INJECTION MOLDING (MELTING

POLYMER)

Plastic materials are supplied in the form of small

pellets into the hopper

The pellets are then gravity fed from the hopper to the

barrel

TECHNOLOGY – INJECTION MOLDING (SCREW)

TECHNOLOGY – INJECTION MOLDING

(SCREW)

Feeding zone:

Pellets crushed together

Air ejected

Transition zone:

Melted by mechanical shear

Metering zone

Melted polymer is homogenized

Ready for injection

Screw moves forward to inject plastic into mold cavity

TECHNOLOGY – INJECTION MOLDING (NOZZLE)

Nozzle

temperature set

to the materials

melt temperature

(160°C).

TECHNOLOGY – INJECTION MOLDING

(INJECTION)

The melt converges at a nozzle and is injected

into the mold.

The melt is forced into the mold in three stages:

Fill stage (mold cavities are filled with molten

resin)

Pack stage (force more melt into the mold to

compensate for shrinkage during cooling)

Hold stage (applies forces against the

material in the cavity until the gate freezes to

prevent leaking of the melt)

TECHNOLOGY – INJECTION MOLDING (COOLING)

Water is circulated in cooling system to remove heat

The air trapped in the cavity passes through narrow

vents

Mold opens

Ejection pins move forward to eject part

Mold closes

Process starts again

TECHNOLOGY – INJECTION MOLDING

(CONCERNS)

Mold cavity not filled up

before solidifying

Shrinking of the plastic

resulting in sink holes

Quality control essential

to ensure product quality

TECHNOLOGY - PRINTING

Offset printing

Screen printing

Digital printing

TECHNOLOGY – PRINTING (OFFSET PRINTING)

TECHNOLOGY – PRINTING (SCREEN PRINTING)

TECHNOLOGY – PRINTING (DIGITAL PRINTING)

Digital printers working with thermal sublimation

dye or retransfer printing are used to print

individual designs onto white cards.

Quality of this technique has not reached the

level of Offset or Screen Printing

Results are well accepted by card issuers.

BENEFITS OF PRINTING TECHNOLOGY

Offset Printing and Screen

Printing

Digital Printing

• Most cost effective when

printing more than 1,000

copies

• No need for preparation

of sheet before printing

• Most accurate process

for colour reproduction

TECHNOLOGY - LAMINATION

Consist of two or more foils, which are pressed

together under high temperatures

Foils are of thermoplastic material, connects

under heat when softening temperature is

reached

For external printing, the surface will be covered

by a transparent varnish

For internal printing, transparent overlay foils

will be laminated over the design which provides

a better resistance against scratching and

abrasion

ADDING MAGNETIC STRIPE AND SIGNATURE

PANELS

Magnetic stripe comes in an overlay foil and is laminated

Paper signature panels are mounted to the outside overlay foil of a card and will connect to the card surface during the lamination process

VIDEO

CONCLUSION

The chosen material is rigid PVC

Manufacturing process involves

Injection Molding

Printing

Lamination

Q & A

Thank you!