Points to be studied? Definition Characteristics of lipsticks Composition Moulding related problems Evaluation of finished products Marketed products
Points to be studied? Definition Characteristics of lipsticks Composition Moulding related problems Evaluation of finished products Marketed products
DEFINITION
• Also called called as lip cosmetics cosmetics,, wi widely dely used by women. women. • It may be refer as color color cosme cosmetics. tics. • Lipstick Lipstick is a cosme cosmetic tic product product containi containing ng p pigme igments, nts, , , texture to the lips. • There There are many varieties varieties of lipstick. lipstick. • Lippy Lippy is a common common British British word for lipstick. lipstick.
Characteristics of Lipsticks
Should cover lips adequately
Long last effect
Make lips soft
Must adhere firmly to lips without being brittle & tacky
Good degree of quality
Completely free from grittiness
-
Non- irritating to skin of lips
Desirable degree of plasticity
Should have high retention of colors intensity without any change in shades
Pleasant odor & flavor
Free from sweating
Shiny & smooth appearance
Easily applicable & removable
Stable both physically & chemically
Composition
Wax mixture
Oil mixture
Bromo mixture
Preservatives
Fragrance
Antioxidants
Surfactants & other additives
WAXES The
gloss & hardness are generally depends on characteristics & quantity of waxes
Best
characteristic is obtained by using m x ure o waxes o eren m.p a us ng the final m.p. by incorporating a sufficient amount of high m.p. wax.
Various waxes used in lipstick Wax
M.P
%
Purpose
Cetostearyl alcohol
42-45
2-3
Emollient
Cetyl alcohol
45-50
2-3
Emollient
Ceresin wax
60-75
5-20
Increase m.p.
White beeswax
62-64
5-20
Bind oils & higher m.p. waxes
Candelilla wax
65-69
5-10
Gives smooth & glossy appearance
Carnauba wax
80-88
1-3
Imparts rigidity & hardness
Hard paraffin
50 - 57
1-5
Improves gloss
Soft paraffin
38 – 56
1-5
Lubricant, increase spreadability
OILS •
The oil mixture is required to blend properly with the waxes to provide a suitable film on the applied lip skin.
•
Also acts as solvent in some formulation.
•
Acts as dispersing agent for insoluble pigments.
•
The ideal mixture of oil should produce the product, easily spread & .
•
Examples: – Castor oil – Tetrahydrofurfuryl alcohol (THFA) & esters – Fatty acid alkylamides – Paraffin oil – Isopropyl myristate – Isopropyl palmitate – Butyl stearate
BROMO MIXTURE • Maintain the physical form of the formulation • Also called as bromo acids • Two classes: – Red : gives red or reddish blue stain –
range , re : g ves p n
o ye ow s p n s a n
• About 2-3% bromo acids are used in lipstick • Solvent used to be mixed with bromo acids: – Castor oil & butyl stearate – THFA & esters like acetate, stearate & benzoate – Glyceryl monostearate or monolaurate & diethylene glycol monostearate –
PG or PEG
• Examples of bromo mixture: – Bromo acid
: 15 gm
– PG
: 200gm
– PG monomyristate
: 100 gm
• Procedure: – Mix bromo acid solution & PG (for clearing each other) – Add PG monomyristate – Which gives bromo acid that easily mixes with mineral oil & castor oil & produces a homogenous mass with waxes.
COLORS •
Most important from commercial & appearance point of view.
•
In olden days, carmine was widely used, but nowadays various other are available.
•
Color in lipstick is imparted by two ways: – outer layer of skin ---- SOLUBLE DYES – By covering the lips with a colored layer which serves to hide any skin roughness & give a smooth appearance ---- INSOLUBLE DYES
• Soluble Dyes / Staining Dyes : – Example: • Fluorescein, • Eosin
• Insoluble Dyes / Nonstaining Dyes / lake colors : – Example: • Lakes of Calcium, Barium, Aluminium, Strontium • Used in 10 – 15 % concentration based on shade
• TiO2 is generally used in conc. of 1% for pink shade
PRESERVATIVES • Used to prevent microbial growth • Example: – 0.1% propyl parahydrohybenzoate in 0.1%
• Higher conc. of preservative can cause slightly burning sensation or allergic reaction.
FRAGRANCE • Essential component of lipstick • Used to mask bad odor of fatty or wax • Used to impart attractive flavor •
. -
• Qualities for selection: – Free from irritating effect – Free from disagreeable taste – Stable & compatible with other ings.
ANTIOXIDANTS • Incorporated to prevent rancidification of oily base
during storage. • Generally used in combination • Example: – BHA, – BHT, – Propyl gallate, – Citric acid
SURFACTANTS & OTHER ADDITIVES •
:Used to promote wetting & stabilize the dispersion of insoluble pigments in lipstick base
•
ADDITIVES:
SURFACTANTS
used for various purposes
– Oil - soluble sunscreen: filter the sunrays & protect lip skin from sun burn. – Silicon fluid: used as fixative & prevent colors, from bleeding on lips. – PVP: (conc. 0.5 – 1%) film former on lips & reduce allergic reaction of other ings. in lipstick. – Isopropyl linoleate: prevent drying effect.
Formula & Procedure Ingredients
Quantity Given
Carnauba Wax
10
Lanolin
5
Cetyl Alcohol
5
Castor Oil
65
Bromo Acid
2% of base weight
Colour Pigment (FeO + TiO2)
5% of base weight
Perfume
q.s.
Bees Wax
15
General Manufacturing Process • Steps involved: – Melting and mixing – Molding – Labeling and packaging
Defects in lipstick • Formulation related
• Mould related
– Sweating
– Laddering
– Bleeding
– Deformation
– Blooming
– Catering
– Streaking
– Mushy Failure
– Seams
FORMULATION RELATED PROBLEMS • Sweating: – Most common problem. – Caused due to high oil content or composition. – It may arise in any climate or temp. range
FORMULATION RELATED PROBLEMS • Bleeding: – Separation of coloured liquids from the waxy base. – distribution
FORMULATION RELATED PROBLEMS • Blooming: – When the surface of the lipstick appears dull instead of desired gloss is called as the problem of blooming. – (> 5%)
FORMULATION RELATED PROBLEMS • Streaking: – A thin line or band of different color or substances appears to the surface of finished products. – particles.
FORMULATION RELATED PROBLEMS • Seams: – Marks left on the lipsticks when split moulds are used. – They are caused either due to brittle masses or due .
MOULDING RELATED PROBLEMS • Laddering: – Product has a ladder like appearance – It does not look smooth or homogeneous after congealing & setting but instead a multilayered appearance. – Occur due to either mould is kept at a very low temperature or when bulk formulation is not hot enough or filling rate is slow.
MOULDING RELATED PROBLEMS • Deformation: – The shape of the lipstick looks deformed. – formulae. – Can appear on side of the lipstick or on both the sides.
MOULDING RELATED PROBLEMS • Catering: – This effect is mostly found in split mouldings. – develops dimples (spots). – The main cause is the presence of trace amounts of silicone oils or machinery lubrication oil from manufacturing mixtures or the dispenser mixture.
MOULDING RELATED PROBLEMS • Mushy Failure: – The central core of the stick lacks structure & breaks. – particular formula or particular shade. – The granularity caused by carnauba wax could be the reason for this problem.
Quality control of Lipsticks • QC procedures are strict • The only cosmetic ingested, because of this strict controls on ingredients & manufacturing processes, are imposed. • Mixed and rocessed in a controlled environment so it will be free of contamination. • Incoming material is tested to ensure that it meets required specifications. • Samples of every batch produced are saved and stored at room temperature for the life of the product
EVALUATION OF FINISHED PRODUCTS
Color
control
Determination
Microbial
of Melting Point ( Heat Test )
Testing
Rancidity Rupture
Test
Breaking
Load Test.
Color control •
Color control of lipstick is critical, and one only has to see the range of colors available from a manufacturer to be aware of this.
•
The dispersion of the pigment is checked stringently when a new batch is manufactured, and the color must be carefully controlled when the lipstick mass is reheated.
•
Colorimetric equipment is used to provide some control on the shades of lipstick.
•
This equipment gives a numerical reading of the shade, when mixed, so it can identically match previous batches.
•
Matching of reheated batches is done visually, so careful time and environment controls are placed on lipstick mass when it is not immediately used.
DETERMINATION OF M.P. •
The lipstick base should have a M.P. between 55 - 750C. (600 C ideal)
•
METHOD: – Sample- approx. 50 mg – Melt & fill into a glass capillary tube open . – Cool the capillary tube with ice for 2 hours – Fasten the capillary tube to a thermometer. – Place a beaker full of water on a heating plate with a magnetic stirrer. – Start heating & stirring at slow & fixed speed. – The temp at which material moves along the capillary tube is considered its M.P
SOFTENING POINT • A lipstick should withstand the range of conditions to which it will subjected in the consumers handbag. • It should be resistant to varying temp & be just as easy to apply in the hot as in cold weather. • Softening point range 50-550C. • Method: – Ring and Ball method – Second Method
SOFTENING POINT Ring & Ball Method •
A ring or support orifice is taken & the lipstick to be tested is inserted into it.
•
Extra mass above & below the orifice is removed using a sharp blade leaving a tablet of lipstick fitted into the ring.
•
This is placed in refrigerator (60C) for about 10 min.
•
Ring is tied onto a stand or bar.
SOFTENING POINT Ring & Ball Method •
A beaker containing 500 ml water at room temp. is placed on a hot plate having a magnetic stirrer.
•
A steel ball is delicately placed on the li stick tablet.
•
The bar is with support is then inserted into the beaker till it submerges into it.
•
Heating & slow agitation is then begun. Temp is monitored using a thermometer.
•
The temp at which the lipstick mass & steel balls are loosened & falls to the bottom of the beaker is the S.P.
SOFTENING POINT Another method • The whole lipstick along with its stand is kept in a long flat bottom tube. • Care should be taken that the lipstick is in a protruded position & the bulb of the thermometer just touches the lipstick mass. • Place this setup in a 1 liter beaker filled with water to a level 1 cm above the upper up of the protruding lipstick. • Start heating water very slowly (@1-20C/min). • The temp at which the lipstick start bending & deforming from its shape is the S.P.
MICROBIAL TESTING • Contamination from raw materials, moulds, storage kettles or lipstick container can lead to microbial growth. • Microbial testing is suggested in IS:9875:1990, • The test consists of plating a known mass of the sample on two selected culture media specifically suitable for the growth of bacteria & fungi & incubating them for a specified period to permit the development of visual colonies for counting. • The limit is, not more than 100 µo/gm.
RANCIDITY • Rancidification is the decomposition of fats, oils and other lipids by hydrolysis or oxidation. • Is the oxidation of castor oil or other waxy or lipoidal ingredients. • It leads to obnoxious odor, bad taste & sticky product & sometimes change of color of the product. • Testing of rancidity can be done by determining its peroxide number.
BREAKING LOAD TEST • The test is to find out the value of maximum load that a lipstick can withstand before it breaks. • The protruded lipstick salve is subjected to a number of weights hanging from it. • The weight at which the lipsticks breaks is its Breaking Load .
BREAKING LOAD TEST • Weights can be replaced by using increasing increments of water from a burette.
Rupture Test
In the Rupture Test, the lipstick is placed in two holders, in the extended position.
Weight is added to the holder on the lipstick portion at 30-second intervals until the lipstick ruptures.
The pressure required to rupture the lipstick is then checked against the manufacturer's standards.
Since there are no industry standards for these tests, each manufacturer sets its own parameters.
Marketed Products • Lakme • ELE- 18
