Types of packaging materials
The following materials are used for the construction ofcontainers and
a. Type-1 borosilicate glass.
b. Type -2 treated soda lime glass.
c. Type-3 regular soda lime glass.
d. Type-4 NP general purpose soda lime glass.
e. Colored glass.
Preparation of glass:
Glass is composed principally ofsand, soda-ash and lime stone. Glass made
from puresilica consists of a three-dimensional network of siliconatoms
each of which is surrounded by 4 oxygen atoms intetrahedral way to produce
1. It is very hard
2. Chemically resistant
3. Structure is less rigid so low m.p.
4. Glass made of pure silica.
Types of glass
Type-1: Borosilicate glass
Eg: pyrex, borosil
Main constituents: Sio2-80%, Al203-2%, Na2o,
Properties: Resistant to chemical substances, reduced leaching action.
Uses: Laboratory glass apparatus, for water forinjection
Type-2: Treated soda lime glass
Main constituents: Made of soda lime glass. Thesurface of which is
treated with acidic glass like so2at Elevated temperature and moisture.
Uses: For alkali sensitive products, Infusion fluids,blood, & plasma,
large volume container.
Properties: The surface of glass is resistant to attackby water for a
period of time.
Type-3: Regular soda lime glass
Main constituents: Sio2, Na2O, Cao.
Properties: Flakes separate easily, many crack dueto sudden change of
Uses: Topical use, For oral use, Not for ampoules.
(Non Parenteral glass or general purposesoda lime glass).
Uses: Topical use, for oral use, not for ampoules.
Main constituents: Sio2 -72 to 75%, B2o3 -7to 10,Na2o -6 to 8%, K2o – 0.5
to 2%, Bao -2 to 4%.
Properties: Lower cost than borosilicate, they aresofter & can easily
Uses: Small vials (25 ml), Large transfusion bottles.
Main constituents: Glass + iron oxide.
Properties: Produce amber color glass, Can resistUv visible radiation
Use: for photosensitive products.
a. Metal containers are strong, relatively unbreakableopaque.
b. Resistance to chemical attack.
c. Impervious to water vapor, bacteria
d. Readily coats a number of metals
This is the most expensive metal among tin, lead,aluminium, & iron. b.
Currently some eye ointments stillpackage in pure tin ointment tubes.
1. Aluminium is a light metal hence the shipment costof the product is
2. They provide attractiveness of tin at somewhatlower cost.
a. As a result of corrosion process H2 may evolve
b. Any substance that react with the oxide coating cancause corrosion.
Uses: Aluminum ointment tubes, Screw capes.
Iron as such is not used for pharmaceutical packaging,large quantities of
tin combines the strength of steel withcorrosion resistance of tin.
Use: fabrication of milk containers, screw caps andaerosol cans.
Lowest cost of all metals used in pharmaceuticalcontainers, Soft metal.
Lead when taken internally there is risk of leadpoisoning. So, lead
containers and tubes should alwayshave internal lining of inert metal or
Use: with lining lead tubes are used for products such asfluoride tooth
General properties of plastics:
Robust, strong, light, aesthetic.
Plastics are synthetic polymers of high molecularweight.
Easy to handle.
They are poor conductor of heat, a disadvantage, ifthe content is to be
Very few types of plastics completely prevent theentry of water vapor and
some are permeable togases like O2, CO2.
Types of plastics
Plastics are classified in to 2 groups according to theirbehavior when
Thermoplastic type: On heating, they soften to aviscous fluid which
hardens again on cooling.
Eg: Polyetyline, Polypropylene, PVC, Polystyrene,Nylon etc.
Thermosetting type: When heated, they maybecome flexible but they do not
usually hard and brittle at room temperature.
Eg: Phenol, Formaldehyde, Urea etc.
Natural rubber consists of long chain polymers ofisoprene units linked
together in the cis portion. Its mostimportant source is the tree Hevea
braziliensis fromwhich latex, containing 30 to 40% of rubber in
colloidalsuspension, exudes when shallow cuts are made in thebark.
A. Butyl rubber:
These are co polymer of isobutylene
with 1-3% of butadiene.
Permeability to water vapor and air is very low.
Water absorption is very low
They are relatively cheaper compared to othersynthetic rubbers.
Slow decomposition takes place above 130°c
Oil and solvent resistance is not very good.
B. Nitrile rubber
Oil resistant due to polar nitrile group, heatresistant.
Absorption of bactericide and leaching ofextractives are considerable.
C. Chloroprene rubber
These are polymers of 1:4 chaperone.
Due to the presence of cl group close to the doublebond so the bond is
resistant to oxidation hencethese rubbers age well.
This rubber is more polar hence oil resistant.
Heat stability is good (up to 1500c).
D. Silicon rubbers
Heat resistance (up to 2500c)
Extreamly low absorption and permeability of water.
Poor tensile strength.
They are very expensive.