· ;.. 'CHEMISTRY CORNER
By Ali N. Syed
Chemical Terms
Cosmetologists
Should Know
Absorption ~ 'When a substance is
entered inside the hair shaft. it is known
Having a pH of 4.0 to 6.0.
Aquatic Balance - A state achieved
to be absorbed. when the hair is infused with and/or
Adsorption· Whcn a substance is retains the level of moisture characteris-
present only on the outer surface of the tics of nonnal human hair.
hair, it is known to be adsorbed. BiocomphHlex - A compound of
Acid- Thc word acid is derived from organic materials, capable of attaching to
the Latin word acidus, meaning sour or the hair. Depending upon the chemical
tart and also related to the Latin word composition, the BiocompHlex can
acetum meaning vinegar. Therefore, serve a number of purposes including
properties commonly \"ssociated with reducing porosity, realigning the cuticle
water solutions of acids are sour or tart layer and deep conditioning within the
in tastc. Acids are rich in hydrogen ions hair shaft.
or protons and they change the color of Cationic - Descriptive of positively-
litmus from blue to red. charged molecules, existing in water
Acidic - The pH of acid solutions miscible conditioners, that adhere to
ranging from 0.\\ to 6.9 and these acid negative and/or damaged sites on the
solutions are called acidic in nature. hair shaft. Cationic conditioners, depen-
Alkali - A water soluble substance dent upon the level and strategy of for-
capable of liberating hydroxide ions mulation, can impart sheen, body and a
(OH) in water. The pH of such a solution silky feel to the hair.
ranges from 7.1 to 14.0. The examples of Cationic Humectants - A combina-
alkaline solutions are sodium hydroxide, tion of cationic compounds and humec-
lithium hydroxide and potassium tant compounds that attach electronically
hydroxide bases which are also termed to damaged areas along the hair shaft to
as \"Iye.\" Guanidine hydroxide is also properly balance moisture levels (also
alkaline in nature. see humectants).
Acid-Balanced or pH Balanced - Chelating Agent - A material which
SHOPTALK 46 APRIL 1994

tics' up calcium, magnesium, or metal Fibrillar Network - . Hydrolyzed - The breaking down of
ions so that they arc no longer effective. A conditioning reparative firm that a substance into smaller components. A
Products with chelating agents have the encases each hair strand to improve the large polypeptide chain of protein, for
ability to extract calcium and magne- hairs overall condition. example, can be hydrolyzed into smaller
sium ions from the surface of the hair Fixative - A chemical agent capable polypeptide chains so that it can pass
fiber, renJering hair more pliable. of stopping the processing of a chemical through the cuticle, penetrate into the
Cortex - The middle or inner layer, hair relaxer and transforming the hair to cortex, and replace the keratin that has
which gives strength and elasticity to its new fonn such as a neutralizer or sta- been lost from the hair.
the hair, is made of a fibrous substance bilizer. Hygroscopic - The ability to attract
formed by elongated cells. This layer Follicle - The tube-like depression moisture from the atmosphere.
contains the pigment that gives the hair or pocket in the scalp containing the Inter-FiberFriction' c The resis-
its color. hair root. tance experienced among hair strands
Cuticle - The outside horny layer, is Fragilitas criniurn - Technical term during combing and brushing; particu-
composed of transparent, overlapping, for brittleness of the hair. larly acute when hair is damaged or
prot\"ective scale-like cells, pointing Guanidine Hydroxide - An organic lacking in proper conditioning.
away from the scalp towards the hair base which is used as a hair straighten· Imbrications - Cells arranged in
ends. Chemicals raise these scales so ing agent with a relatively low potential layers overlapping one another; found
that solutions can enter into the hair cor- for scalp irritation. in cuticle layer of hair.
tex. The cuticle protects the inner Struc- Hair Bulb - A thickened, club- Internal Molecular Flow - A phe-
ture of the hair. shaped structure fanning the lower part nomenon that occurs during the perma-
Cysteine - An amino-acid easily of the hair root. The lower part of the nent waving process (before oxidation)
oxidized to cystine; obtained by the bulb is hollowed out to fit over and whereby the molecules of the hair have
reduction of cystine, cover the hair papilla. adjusted to their new curly/wavy con-
Cysteine Bonds - When cystine Hair Papilla - A small cone-shaped figuration. The significance of this
bonds arc reduced or broken in the mid- elevation located at the bottom of the process is that when complete, the curl
dle by reducing agents like Ammonium hair follicle which fits into the hair bulb. and wave patterns are strengthened.
Thioglycolate. It is through the papilla that nourish- Keratin - The hard protein of which
Cystine - A sulphur contain- ment reaches the hair bulb. The papilla hair is composed.
ing amino-acid found in hair and nails. has the ability to produce hair cells. As Lanthionization-The process
Cystine Cross-links - Disulfide long as the papilla functions, the hair whereby hair is permanently relaxed or
bonds within the hair that connect or will grow. straightened. It involves changing one-
cross-link two polypeptide chains Hair Root - That part of the hair third of the hairs cystine bonds (which
(much like the rungs of a ladder.) contained within the hair follicle consists of two sulfur atoms) to lanthio-
Diameter of Hair (Coarse, medium beneath the skin's surface. nine bonds (consisting of one sulfur
or fine) - Coarse hair has the greatest Hair Shaft - That portion of the hair atom). Sodium hydroxide and guanide
diameter. Fine hair has the smallest. which projects beyond the skin. hydroxide are two commonly used
Elasticity - The ability of the hair to Hair Test - A sampling of how the active ingredients that effectively lan-
stretch and return to its original length hair will react to a particular treatment. thionize excessively curly hair.
without breaking. Normal hair has its Humectants - Chemical substances Macrofibrous - Descriptive of cer-
limitations as to the amount of pull or capable of attracting moisture from the tain conditioning materials that are in
pressure it can withstand. Under normal atmosphere onto the hair shaft (i.e., the form of relatively large thread-like
conditions, the hair can be safely glycerin, propylene glycol). Especially particles, similar in structure to the cor-
. - - stretched about one-fifth of its length. beneficial for moisturizing dry, brittle tex of the hair. They effectively fill in
Hair that has normal elasticity presents hair and retaining proper moisture bal- larger cavities and damaged sites on the
a healthy and lustrous appearance. A ance. hair shaft, to leave hair smooth, soft,
deficiency in the elasticity of hair caus- Hydrator - A substance capable of shiny, silky feeling and very easy to
es it to become lifeless and limp. Very adding moisture to the hair. comb. (These macrofibrous condition-
little elasticity is left in hair that has Hydration - The act of adding water ing agents are present in Affirm™ 5 in
been abused by overprocessing during to a substance or material. Relative to 1 Reconstructor.)
chemical services. hair care, hydration refers to adding Medulla - The innermost layer, is
Elipticity -The cross-sectional moisture with humectants and other referred to as the pith, or marrow of the
shape of hair. Hair assumes the shape, conditioning agents, to correct or pre- hair shaft, and is composed of round
size and direction of the follicle. It is a vent dryness. cells. The medulla may be absent in fine
ratio of major and minor axis in the Hydrogen Bonds or H-Bonds - and very fine hair.
cross-section of hair. African hair has The cross-bonds or links that are more Melanin - The dark or black pig-
elipticity of 1.89 whereas caucasian and numerous than sulfur bonds, but they ment in the epidermis and hair.
oriental hair have elipticity of 1.4 and are much weaker and can be broken
1.1 respectively. easily with water Or chemicals. Continued on page 53
SHOPTALK 47 APRIL 1994

· ~
aM'\" very tightly. inhibiting the absorption mine the speed at which the natural
Chemistry Corner of conditioners. curl is being removed.
Pilus- Plural for \"pili.\" meaning Semi Permanent Hair Color -
Continuedfrom page 47
hair. Hair color formUlated to last from 4-6
Polypeptide - Strings of amino shampoos. [t penetrates the hair shaft
Microfibrous - Descriptive of cer- acids joined together by peptide bonds, slightly. depending on the porosity of
taio conditioning m~terials that are in the prefix \"poly\" meaning many. the hair. Uses no peroxide for develop-
the form of very small spiderweb-like Polypeptide Chains - A complex ment.
particles. They act as fillers in the tiny internal structure within hair, character- Strain - The degree or percentage
crevices and damaged sites on the hair ized by linkages of various amino of stretching of a hair fIber under cer-
shaft, to even out porosity, smooth cuti- acids. tain degrees of stress or force.
cles and strengthen hair temporarily. Porosity - Ability of the hair to Stress - The pull or force put on the
No-Base Relaxers - Creme relaxers absorb moisture due to lifted cuticle hair during combing, brushing, styling
that contain adequate amounts of petro- layers. or simply stretching while detennining
latum and/or mineral oils to help protect Positively-Charged Compounds - elasticity of hair.
the scalp against the irritating effects of Descriptive of a very large number of Sulfur Bonds or S-Bonds - The
sodium hydroxide or guanidine hydrox- different agents that attach electronical- cross bonds or links that are very
ide. The need to manually apply oils to ly to the negative sites of the hair shaft. strong and can only be broken by a
the scalp is virtually eliminated. (The normal hair strand has a balance strong chemical.
Normal Hair Shedding - The aver- of both positive and negative charges. Temporary Hair Color - Hair
age daily hair shedding is estimated at Should the hair become damaged, the color which coats the cuticle and is for-
50-80 hairs. Hair loss' beyond this esti- number of negative sites increases.) mulated to last only from shampoo to
mated average indicates some scalp or Depending upon the specific compound shampoo.
hair trou bie. of grouping of compounds, the effect Tensile Strength - The amount of
Overlapping - Condition caused by will be to reduce combing friction, pull or pressure that can be induced on
a relaxer touch-up when the cream over- realign the hair shaft, make hair more a single hair fiber without breakage.
laps onto previously treated hair. The pliable, improve the optical qualities of Texture - The general quality of
result of overlapping during a relaxer hair (i.e. shine and fullness). eliminate hair, [l:; to coarse, medium or fine; the
application is usually severe hair dam- static electricity, lubricate the hair feel of hair.
age or breakage. shaft. etc. Thio (Ammonium Thioglycolate) -
Oxidizing Lotion - A solution used Protein - A complex organic sub- Chemical hair relaxer.
in the permanent waving process which stance present in all living tissues, such Touch-up - The application of
is rich in oxygen-containing compounds as skin, hair and nails; necessary in the relaxer to the new growth of the hair,
(i.e. sodium brom~ltc and hydrogen per- daily diet; also present in skin and hair being extremely careful not to overlap
oxide). It works to reform the reduced conditioners. onto previously treated hair.
cystine (cysteine) bonds and lock-in Pull Test - A test to determine the Trichoptilosis - A splitting of the
the new curl or wave pattern. degree of elasticity of the hair. hair ends, giving them a feathery
Peptide - A compound of two or Redox - The process whereby curls appearance.
more amino-acids containing one or or waves are chemically and perma- Trichorrhexis Nodosa - Disease
more peptide groups; continuous fila- nently formed into hair. It involves two of the hair shaft initially characterized
ments in the case of fiber protein or ker- distinct chemical processes: reduction by nod-like structures eventually lead-
atin. and oxidation. Reduction entails the ing to shredding and weakened areas
Permanent Hair Color - Hair color cleavage of breakage of cystine bonds along and within the hair shaft, leaving
formulated to penetrate the cuticle and via rearrangers. The altered bonds are the cortex fibers exposed and fraying.
deposit molecules of pigment into the called cysteine bonds Or half cystine As the hair is combed and styled. the
cortex. Permanent hair color usually bonds. Oxidation is accomplished implements snag the damaged sites.
contains an aniline tint, which is a coal- when oxidizing solution (formulated causing more extensive damage and
tar derivative. These penetrating tints with sodium bromate or hydrogen per- eventual breakage. Common causes are
can lift and deposit color in one step. oxide) is applied to rodded hair. As the mechanical, thermal, chemical and/or
pH (Potential Hydrogen) - A mea- hair is neutralized, the majority (80- environmental (i.e. sun) damage.
surement ranging from 0 to 14.0 that 85%) of cysteine bonds are reformed Upper Mantle - The outermost sur-
measures the relative degree of acidity back to cystine bonds. The new curl face of the hair shaft (cuticle).
or alkalinity of a substance. Healthy pattern is then locked into the hair per- Virgin Hair - Hair that has had \"0
hair and scalp are slightly acidic, at a manently. chemical services or damage from nat-
pH of 4.5 - 5.5 and are only balanced Relaxer - A chemical applied to the ural factors such as wind, sun, etc.
within this range. At a high (alkaline) hair to straighten excessively curly
,lH, the hair shaft swells and cuticles are hair.
opened. At a low (acidic) pH, the hair Relaxer Testing - Checking the Ali Syed is president and master chemist of AvIan
shaft contracts and cuticles are closed action of the relaxer in order to deter- Industries. Bedford Park. It.
SHOPTALK 53 APRIL 1994