© 2012 Milady, a part of Cengage Learning

Milady Standard Cosmetology

Chemical Texture Services

The Structure of Hair

• Cuticle: Tough exterior layer of hair.

• Cortex: Middle layer of hair.

• Medulla: Innermost layer of the hair, often called pith or core of the hair.

The Structure of HairImportance of pH in Texture Services

• pH scale: Measures acidity and alkalinity of a substance by measuring the quantity of hydrogen ions it contains.

• Natural pH of hair is between 4.5 and 5.5.

• Chemical texturizers: Raise the pH of the hair to an alkaline state in order to soften and swell the hair shaft.

The Structure of HairBasic Building Blocks of Hair

• Amino acids

• Peptide bonds (end bonds)

• Polypeptide chains

• Keratin proteins

The Structure of HairBasic Building Blocks of Hair

• Side bonds

• Disulfide bonds

• Salt bonds

• Hydrogen bonds

Permanent Waving

• Permanent waving: Two-step process whereby hair undergoes a physical change chemical change.– Always perform an

elasticity test before perming hair.

Permanent WavingPerm Wrap

• Perm wrap: Wet set on perm rods instead of rollers.

• Shape and type of curl are determined by shape and type of rod and wrapping method used.

Permanent WavingTypes of Rods

• Concave rod

• Straight rod

• Soft bender rod

• Loop rod (circle rod)

Permanent WavingEnd Papers

• End papers: Also end wraps; absorbent papers used to control ends of hair when wrapping and winding hair on perm rods.– Double flat wrap– Single flat wrap– Bookend wrap

Permanent WavingSectioning for a Perm

• All perm wraps begin by sectioning the hair into panels.

• Base sections: Subsections of panels into which the hair is divided for perm wrapping.

Permanent WavingBase Placement

• Base placement: Refers to position of rod in relation to its base section.– On-base placement– Half off-base

placement– Off-base placement

Permanent WavingBase Direction

• Base direction: Refers to angle at which rod is positioned on head: horizontally, vertically, or diagonally.

Permanent WavingWrapping Techniques

• Croquignole perm wrap

• Spiral perm wrap

• Double-rod wrap (piggyback wrap)

Permanent WavingThe Chemistry of Permanent Waving

• Alkaline permanent waving solutions soften and swell the hair, opening cuticle and permitting solution to penetrate into cortex.

Permanent WavingReduction Reaction

• In the cortex, waving solution breaks disulfide bonds through reduction.

• Reduction reaction in permanent waving is due to the addition of hydrogen.

• Thioglycolic acid: Most common reducing agent in permanent wave solutions.

• Ammonium thioglycolate (ATG): Active ingredient or reducing agent in alkaline permanents.

Permanent WavingTypes of Permanent Waves

• Alkaline waves or cold waves

• Acid waves• True acid waves• Acid-balanced waves• Exothermic waves• Endothermic waves• Ammonia-free waves• Thio-free waves• Low-pH waves

Permanent WavingSelecting the Right Type of Perm

• Overprocessed hair• Underprocessed hair• Thio neutralization:

Stops action of waving solution and rebuilds hair into its new curly form.

Permanent WavingPermanent Waving Procedures

• Preliminary test curls• Wrapping patterns

– Basic permanent wrap (straight set wrap)

– Curvature permanent wrap

– Bricklay permanent wrap

– Weave technique

• Partial perms

Permanent WavingPerms for Men/Safety Precautions for Permanent Waving

• Male clients are looking for the texture, fullness, style, and low maintenance a perm provides.

• Perm safety– Protect client’s

clothing.– Do not give to clients

who have had allergic reactions.

– Examine scalp before service.

– Do not perm damaged or relaxed hair.

Permanent WavingSafety Precautions/Metallic Salts

• Perm safety (cont.)– Test for metallic salts.– Use a barrier cream.– Follow manufacturer’s

guidelines.– Keep waving lotion

away from client’s eyes.

– Wear gloves.– Do not safe leftover

solutions.

• Some home haircoloring products contain metallic salts that are not compatible with permanent waving.– Test for metallic salts

before perming.

Chemical Hair RelaxersExtremely Curly Hair

• Chemical hair relaxing: Process or service that rearranges the structure of curly hair into a straighter or smoother form.

• Extremely curly hair grows in long twisted spirals, or coils.

Chemical Hair RelaxersThio Relaxers/Japanese Thermal Straighteners

• Thio relaxers: Use same ATG used in permanent waving, but at a higher concentration and higher pH.

• Japanese thermal straighteners: Also thermal reconditioning or TR; combines use of a thio relaxer with flat ironing.

Chemical Hair RelaxersHydroxide Relaxers

• Hydroxide relaxers: Very strong alkalis with a pH over 13.

• Lanthionization: Process by which hydroxide relaxers permanently straighten hair.

• Types:– Metal hydroxide

relaxers– Lye-based relaxers– No-lye relaxers

Chemical Hair RelaxersLow-pH Relaxers/Base and No-Base Relaxers

• Sulfites and bisulfites are sometimes used as low-pH hair relaxers.

• Base cream: Also protective base cream; oily cream used to protect skin and scalp during hair relaxing.

• Base relaxers: Require application of protective base cream to entire scalp prior to application of relaxer.

• No-base relaxers: Do not require application of protective base cream.

Chemical Hair RelaxersRelaxer Strengths

• Chemical hair relaxers are available in three strengths: mild, regular, and super.

• Periodic strand testing during processing will help you tell when the hair is sufficiently relaxed.

Chemical Hair RelaxersHydroxide Relaxer Procedures

• Virgin relaxer application: Used for hair that has not had previous chemical texture services.

• Retouch relaxer application: Used for hair that has had previous chemical texture services.

• Texturizing or retexturizing service: Uses a hydroxide relaxer to reduce curl pattern by degrees.

• Normalizing lotions: Conditioners that restore hair’s natural pH after a hydroxide relaxer.

Chemical Hair RelaxersKeratin Straightening Treatments

• Keratin straightening treatments: Contain silicone polymers and formalin, or similar ingredients, which release formaldehyde gas when heated to high temperatures.

– Eliminate up to 95 percent of frizz and curl and last three to five months.

– Not usually appropriate for extremely curly, tightly coiled hair.

Curl Re-Forming (Soft Curl Permanents)Safety Precautions for Hair Relaxing and Curl Re-Forming

• Soft curl permanent: Combination of thio relaxer and thio permanent wrapped on large rods to make existing curl larger and looser.

• Safety:– Perform a consultation and

hair analysis.– Examine the scalp for

abrasions.– Keep accurate client

records.– Have client sign a release.– Do not apply hydroxide

relaxer on hair previously treated with a thio relaxer.

Curl Re-Forming (Soft Curl Permanents)Safety Precautions

• Safety (cont.)– Do not apply thio relaxer or soft

curl perm on hair that has been treated with hydroxide relaxer.

– Do not chemically relax hair that has been treated with a metallic dye.

– Do not relax damaged hair.

– Do not shampoo prior to application of hydroxide relaxer (scalp must be dry).

– Apply protective base cream.

– Wear gloves.

– Protect client’s eyes.

– Perform strand tests.

– Avoid scratching the scalp.

– Do not attempt to remove more than 80 percent of natural curl.

– Thoroughly rinse chemical relaxer from hair.

– Use normalizing lotion and neutralizing shampoo.

– Use conditioner and wide-tooth comb.

– Do not use hot irons or excessive heat on chemically relaxed hair.