Deodorants Flashcards
- Regulated by sympathetic nervous system
- Body temperature regulator
- Remove waste and toxic by-products from the body
- Odorless, but bacterial and heat decomposition yields
volatile by-products with unpleasant odor
Sweat
the 2 types of sweat glands are present at birth (t or f)
T
- Simple, coiled tubular glands with duct that leads directly onto skin surface
- Where antiperspirants take action
- exist and function from birth
- found all over the body
- Controls body temperature and electrolyte balance
eccrine sweat glands
- under psychological and thermal control
- Secretion contains water, salts, amino acids, peptides,
and electrolytic components (should be no odor at all) - Considered as true sweat gland
eccrine sweat glands
- Limited to axilla, anus, and breast
- Larger than eccrine glands
- Ducts open into hair follicle duct
- Exist at birth, but become functional at puberty
- Triggered by emotions
- Secretion is odorless and viscous
apocrine sweat glands
- Topically-applied products designed to reduce or mask
unpleasant body odors by re-odorization and/or antibacterial action
deodorants
deodorants cannot be used as anti-perspirants (t or f)
T
- Topically-applied products designed to reduce underarm
wetness by limiting body transpiration
ANTIPERSPIRANTS
Antiperspirants inhibit perspiration secreted by _________ usually by forming a temporary plug within the sweat
duct
eccrine glands
- Excessive sweating
- Profusion of sweat in the axillary sites palms, feet, face,
trunk, or combination of these - Excessive sweat lead to unpleasant body odor that can
adversely affect the person’s ability to attain a normal
and healthy quality of life (QoL) - May require non-cosmetic antiperspirants
hyperhidrosis
REQUIRED PRODUCT CHARACTERISTICS
- Neutral or pleasant odor
- Easy to spread
- Pleasant feeling during application
- Well-tolerated and non-allergenic
- Long-term deodorization
- Quick-drying properties
- Non-staining properties
- ODOR MASKING
- ODOR NEUTRALIZING
- ODOR QUENCHING
- ODOR ABSORBING/ADSORBING
- ESTERASE INHIBITORS
- ANTIMICROBIAL INGREDIENTS
- ANTIPERSPIRANTS
Mechanisms of Action
- Most common mechanism
- Ingredients reduce the perception of odor through
blending with underarm, odor, and masking it - Example: Fragrances
ODOR MASKING
- Agents chemically neutralize odors compounds to yield
odorless components - There is chemical reaction involved
> Reaction between the neutralizing agent and
odorous compound
> Yield odorless component
ODOR NEUTRALIZING
ODOR NEUTRALIZING examples
- Sodium bicarbonate
- Potassium bicarbonate
- Zinc carbonate
- Ingredients bind to odorous chemicals and form complexes with these materials
- EDTA is the most powerful chelating agent
- chelation or sequestering
ODOR QUENCHING
ODOR QUENCHING examples
- Zinc ricinoleate
- Zinc oxide
- Hydroxyapatite
- Ingredients physically neutralize odorous molecules
formed in the axilla via absorption or adsorption to
decrease perceived odors
> Bad odors are volatile
> Physical neutralization thru abs/adsorption: Less volatility → Less perception of BO
ODOR ABSORBING/ADSORBING
ODOR ABSORBING/ADSORBING
examples
- Resins
- Silicates
- Act by directly inhibiting enzymes of the underarm
bacteria, or by shifting the pH optimal for the development of underarm odor (pH 6) to acidic range, which results in odor reduction
ESTERASE INHIBITORS
ESTERASE INHIBITORS examples
- Zinc glycinate: Inhibits enzymes of bacteria
- Citric acid derivatives: Lowers pH
- Prevent underarm odor by inhibiting or deactivating the
bacteria responsible for bad odor formation
> Can help in deodorization
ANTIMICROBIAL INGREDIENTS
ANTIMICROBIAL INGREDIENTS
- Ethanol
- Triclosan
- Sucrose monostearate
- Essential oils like thyme and clove oil
- Reversibly block sweat gland secretion by forming a
temporary, gelatinous plug in the eccrine duct - Action is not permanent; we have to continuously apply
ANTIPERSPIRANTS
- Aluminum chloride
- Aluminum chlorohydrate
- Aluminum sesquichlorohydrate
- Aluminum sulfate
ANTIPERSPIRANTS: Aluminum-based agents
- Buffered with glycine to stabilize them and mitigate acidic harshness resulting when applied to underarm axilla
- Common agent that is used for antiperspirant: Tawas (aluminum-sulfate salts)
ANTIPERSPIRANTS: Aluminum-zirconium based agents
Types of DEODORANTS & ANTIPERSPIRANTS
- roll ons
- solid sticks
- extrudable clear gels
- extrudable soft solids
- aerosols
types of roll-ons
- Water-based
- Hydroalcoholic
- Silicone-based
- Usually opaque O/W emulsions
> cannot be water only because the active ingredient is not really water soluble - Based on non-ionic surfactants
- Advantage: Less irritating than hydroalcoholic
> can be used for sensitive skin - Disadvantage: Dries slower than hydroalcoholic
Water-based roll-ons
- Have a shorter drying time
- Offers a refreshing feeling on application
- Contains only alcohol-soluble actives, usually thickened with hydrophilic polymer
- Emollients and silicones can be incorporated with product emulsifiers
> Emollients and silicones - moisture
> Add emulsifiers because these two are not completely miscible with alcohol
Hydroalcoholic roll-ons
- Can be formulated as anhydrous products
> Actives are suspended in volatile silicone oils like cyclomethicone - May be thickened with non-surfactant suspending agents like quaternium-18 to minimize powder sedimentation
> Cannot be a water-based thickening agent like polymers
> Aluminum is thick, needs dispersion in a suspension
Silicone-based roll-ons
types of solid sticks
- deodorant sticks
- antiperspirant sticks
- Based on sodium stearate as gelling agent
- Deodorizing agents and fragrances are dissolved in hydrophilic vehicle based on water and propylene glycol
- To make the formulation more transparent: Nonionic surfactants
Deodorant sticks
To make the formulation more transparent: Nonionic surfactants, like ________
- PG-3 myristyl ether
- Isosteareth-20
to improve stability of deodorant sticks
- Preservatives,
- Antioxidants, and
- Chelating agents
- Usually anhydrous suspension containing suspended antiperspirant actives in
silicone-based vehicles
antiperspirant sticks
antiperspirant sticks
- Quick-drying and dry skin feel
- Cyclomethicone
- Cyclopentasiloxane
antiperspirant sticks
- Soft skin feel and glideability
- Myristyl myristate
- Octyldodecanol
antiperspirant sticks
- Dispersing agents
PPG-4 butyl ether
antiperspirant sticks
- Give structure to the stick and act as lubricant
- Stearyl alcohol
- Behenyl alcohol
- Hydrogenated castor oil
antiperspirant sticks
- Thickener
- Quaternium-18 hectorite
antiperspirant sticks
- Suspending agent
- talc
- silica
- W/Si emulsions that appear as transparent formulations
which are often associated by consumers with a lack of
white residue on the skin
> If we have 2 phases, they become transparent
when we match their refractive index - Antiperspirant actives dissolved in water
> May also contain alcohol and humectants - Blend of cyclomethicone and dimethicone copolyol help
disperse and solubilize actives - Special silicone blends are used to stabilize the emulsion
EXTRUDABLE CLEAR GELS
- Usually white anhydrous silicone suspensions pastes
- Rub-in quickly, non-tacky, leave little residue on skin, and deliver high levels of antiperspirant protection
EXTRUDABLE SOFT SOLIDES
EXTRUDABLE SOFT SOLIDES:
Powdered active is suspended in ______________________
- Silicone (cyclopentasiloxane) and/or
- Hydrocarbon (isohexadecane)
EXTRUDABLE SOFT SOLIDES:
Paste is thickened with waxes like
______________________
- C18-36 acid triglyceride and
- Tribehenin
- Popular due to hygienic and easy-to-use product form
aerosols
- Contain a solution of deodorant ingredient blended with liquefied propellant
- Provide a dry skin feeling as anhydrous formulations
Deodorant aerosols
deodorant aerosols propellants
Propane, butane, and isobutane
- Anhydrous formulations wherein antiperspirant
actives are suspended in the product - Vehicle consists of volatile silicone oils
- Suspending agents are used to stabilize product
- Usually shaken before use
Antiperspirant aerosols
Antiperspirant aerosols:
suspending agents used to stabilize product
- Stearalkonium bentonite
- Hectorite
Antiperspirants are generally insoluble in water (t or f)
F
Aluminum powders tend to leave a visible white residue
on the skin or clothing when formulated into anhydrous
systems (t or f)
T
Antiperspirants have an acidic pH (4.0 to 4.2) when dissolved in water (t or f)
T
Antiperspirant aerosols contain actives in dissolved suspended state (t or f)
F
Antiperspirants actives are insoluble in sweat (t or f)
F
Antiperspirant actives are more readily available and effective in water-phase is the internal phase of emulsions (t or f)
F
- Shrinkage of Extrudable gel
- Caking of aerosols
- Valve clogging (For aerosols)
- Staining and fabric
damage (Yellow stain) - Poor pay-off (For sticks - Hard to apply or does not stick to skin)
quality problems
Volatility of alcohol
in formulations
cause of Shrinkage of
Extrudable gel
Addition of humectants to
reduce alcohol lost
remedy of Shrinkage of
Extrudable gel
Settling of actives at
the bottom of the can
cause of Caking of aerosols
Use of thickeners like bentonite
remedy of caking of aerosols
Large particle sizes, High thickener concentrations, or Improper valve system
cause of Valve clogging
- For aerosols
Use of silicone oils
remedy of valve clogging
Build-up of aluminum salts from
the product, acidic pH of perspirants
cause of Staining and fabric damage
- Yellow stain
Soaking in slightly alkaline solution
- Neutralize acid
remedy of staining and fabric damage
Improper type and/or Insufficiently high concentration of hardening agents
cause of Poor pay-off
- For sticks
- Hard to apply or
does not stick to
skin
Proper selection of ingredients
remedy of poor pay-off
- More on deodorants
- Cultivation of selected bacteria on agar plates, and evaluation of microbial growth after incubation period
- Not reliable to indicate true potential of formulation for
malodor control
> Antimicrobial action is being tested, not directly the reduction of malodor
IN VITRO MICROBIOLOGICAL TESTING
- Sensory assessment of body odor by expert sniffers
- Intensity of body odor is evaluated while test subjects
perform normal activities
IN VIVO SNIFF TEST
- Subjects use perfume-free, non-bacterial soap, with no antiperspirant for several days
IN VIVO SNIFF TEST: Preconditioning phase
Use of test (left armpit) and control (right armpit) formulations for few days
IN VIVO SNIFF TEST: Testing phase
Antiperspirant should meet:
>Minimum of 20% sweat reduction in at least
50% of test population for standard effectiveness OR
>Minimum of 30% sweat reduction in at least 50% of test population for extra effectiveness
SWEAT REDUCTION TEST FOR ANTIPERSPIRANTS
Test subjects must produce
- at least 100 mg of sweat
- during 20 minutes
- in a controlled environment
SWEAT REDUCTION TEST FOR ANTIPERSPIRANTS
SWEAT REDUCTION TEST FOR ANTIPERSPIRANTS (no. of days)
25 days
- no application of any products on the axillae
- use of unscented mild soap provided by laboratory to daily clean armpits at home
Preconditioning period
day 1 to day 17
Preconditioning period
day 18
baseline
- section of volunteers having sufficient sweat rates and sweat odour intensity
baseline`
day 19 to day 23
product application (5 days)
- 5 application: once a day
- randomized balanced design: test product on one side/ placebo on the other side
product application (5 days)
day 24
24 hours efficacy
- ambient conditions
- sweat collection period (4hrs)
- gavimetric and sweat odour intensity evaluation
- statistical analysis
day 24 and day 25
48 hours efficacy
day 25
