Carpet Cleaning Products

_______________________________________
Advanced Carpet Cleaning
Technical Manual

By Jeff Cross
Senior Editor
Cleanfax magazine
jcross@ntpmedia.com

Copyright 2009, all rights reserved

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Table of Contents

The fiber basics

Characteristics of fiber types

Fiber ID

Fiber/carpet dyeing (color)

Identifying dye or color problems

Carpet construction (manufacturing)

Carpet soiling

Cleaning, practical application, chemistry

pH specifications

Principles of cleaning

Methods of cleaning

Deodorizing techniques

Problems you will encounter

Advanced spot and stain removal

Stain Wheel

Stain Zapper Reference Guide

Worksheets


Special thanks to my colleagues Tony Wheelwright, Jim

Smith, Jeff Bishop, Bill Yeadon and many others for some of

the artwork and graphs in this publication.

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The fiber basics

Natural fibers found in carpet and rugs

Natural fibers aren’t as common as synthetics, but they are

found often enough that it is important to know what they are and

which specific cleaning techniques/chemicals should be used.

These are fibers that originate from plants, animals and

insects.

Most natural fabrics are very absorbent and require special

care and skill, especially with the chemistry used in your cleaning

process.

Protein fibers

1. Protein fibers come from animal or their by-products (wool

and silk). Sodium hypochlorite, also known as common

household (chlorine) bleach, will soften and even completely

dissolve protein fibers, causing permanent damage.

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2. Protein fibers are naturally flame resistant, and normally

will hide dirt and give fabrics a “warm” look and feel. For

commercial applications, this is a consideration, as more

architects and building maintenance managers are

concerned with safety (flammability).

Wool specifics

The fleece of a sheep or lamb

This three-part fiber (epidermis – the

outer layer of the fiber – cortex and

medulla) dates back to 2,000 BC. Wool

has a natural crimp which makes it

resilient (bounces back when crushed).

Use care with alkalinity. Most cleaning

chemicals are alkaline. Best practice is to

clean wool fibers between 4.5 and 8.5 on

the pH scale. It’s better to play it safe

and keep your cleaning chemistry close to neutral or slightly

acidic. Dye migration can

occur with high pH.

When agitating wool fibers,

be cautious. You can “felt” the

fabric. Felting is the

interlocking of the scales of

the wool fiber and can make

the carpet appear “slimy”

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during cleaning. Felting is also caused by high alkalinity.

Only use fluorochemicals as fabric protectors (Teflon,

Scotchgard, various brands). Silicones block the pores of wool

fibers, causing degradation (and resoiling).

Wool can be damaged and degrade and lose strength if left for

prolonged time periods in direct sunlight.

Lamb wool is the first fleece that is sheered from a sheep that

is eight months or younger. It is soft and fine compared to

subsequent sheering.

Virgin wool is wool that has never been processed.

Pulled wool is fleeced taken from dead animals and is most

often used in making

wool carpet fibers.

Wool hides dirt, so the

carpet may have much

more soil than first

estimated.

Wool can sustain insect

growth.

Bleeds (with moisture),

crocks (with or without

moisture).

Silk specifics

Produced by the silkworm, it is the strongest of all natural

fibers.

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Silk fibers will easily watermark, so be sure to clean them

evenly.

You won’t find silk in a manufactured carpet… it’s listed here

because you will see it in some area rugs.

Texture distorts easily.

Yellows with age.

Spots easily.

Damaged by alkaline and perspiration.

Cellulosic fibers:

These come from plants or

vegetation.

Examples are cotton and jute.

Only these fibers can have

“cellulosic browning” from “lignin”,

the substance in plant matter.

Alkaline agents (see section on

“chemistry” later in this

manual) intensify this,

and are not effective in

removing browning. If

you need alkalinity (such

as ammonia), always

neutralize with an acid

(such as citric or acetic –

vinegar).

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Using too much water or not drying a fabric fast enough

contributes to browning.

Cotton is highly absorbent which means longer drying times.

These fibers are taken from the seed hairs of the cotton plant

via ginning.

Jute is made from the stalks of the jute plant. It is used mostly

as a secondary backing on tufted carpet and warp and fill

yarns for woven carpet, and blended with sisal for mats. It has

good dimensional stability and resistance to dry heat. But it

may shrink and rot or brown with over wetting and improper

drying. Natural fibers may take longer to dry because they are

more absorbent then synthetic fibers.

Other natural fibers found in carpet and rugs include coir

(coconut husk), seagrass and sisal (agave plant) – use low

moisture cleaning with these fibers and wet the surface evenly.

Absorbent compound cleaning is safe and effective.

Sisal rugs (like many natural

wood/grass/reed fibers) need low

moisture cleaning. This

can be done with less water or

with an absorbent

compound cleaning

system.

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Synthetic fibers found in carpet and rugs

Synthetic fibers are man-made and manufactured by one of

three spinning methods, and are often referred to as “extrusion.”

Extrusion is the process in which liquid polymers are spun into fiber,

much like water coming from a shower head. These fibers are then

cooled in a cooling chamber until solidified.

They can be

extruded to look “shiny,”

or “delustered,” based on

the shape of the aperture

of the spinnerette (the “showerhead”

device that creates the shape and

denier – thickness – of the

filament in the spinning

process). Crimping

following extrusion creates

“bulk” in fibers. When two

or more fibers (called

“filaments”) are twisted

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together, a “plied” yarn is created, with greater strength, similar to a

twisted rope. Heat setting allows the yarn to retain shape.

When the fiber is not cut into small lengths, it is called “bulk

continuous filament” or BCF. When cut into small lengths, the term

is “staple” fiber.

Natural fibers (except

silk) are staple fibers,

because they are short

lengths. In theory, BCF

fibers can be produced

continuously, with no

end.

All fibers, as a

best case scenario,

should be cleaned with

a pH less than 10.

Nylon

Nylon was developed in the 1930s by Dr. Wallace Carouthers and is

the most popular face fiber used in carpet manufacturing today.

Nylon is dissolved by formic acid, and melts at 425 degrees

Fahrenheit.

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It is resilient – springs back when crushed – has low soil

absorbency, and is dyed mainly with acid dyes. Solution dyeing

(pigmented dyeing) is also used.

Very popular blended with olefin, especially in commercial

applications.

The five generations of nylon

development:

1. First generation: Round,

strong, durable and shiny,

but magnified soils.

2. Second generation: Tri-

lobial, giving it soil hiding

abilities (modified cross-

section).

3. Third generation: Modified

cross-section…built-in anti-

static properties, using

carbon-core in the nylon

yarn. (Most static problems

are found during low-

humidity periods, such as

wintertime).

4. Fourth generation: Modified

cross-section, anti-stat and

soil/stain repellency

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(fluorochemical, such as Scotchgard, Teflon) added.

5. Fifth generation: Modified cross-section, anti-stat,

soil/stain repellency

(fluorochemical), and stain

resistance (acid dye blockers –

“Stainmaster”) added. The specific

fifth generation technology was

the acid dye blockers inside the

yarn, not the surface treatment. Clean with pH 10 or

less.

Types of nylon in carpet:

Type 6: Single unit nylon polymer, easily dyed and

also easier to stain or fade.

Type 6, 6: Double unit nylon polymer, harder to

dye but also harder to stain or fade.

Nylon is known best as the fiber with soil and stain

resistant capabilities due to mill application of

fluorochemicals and stain blockers (acid dye blockers)

because nylon has open “dye sites” (think of a sponge)

which can stain from “acid dyes”. These chemicals must

be added because of all the synthetics, nylon stains the

easiest. You can test for both of these products: To test

for the fluorochemical application, a small amount of

water added to the carpet pile will bead up. If not, add

more fluorochemical after cleaning. To test for stain

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resistance, wet a fiber with an acid dye such as Kool Aid,

allow to dwell for several minutes, and flush with water.

If severe staining occurs, the product probably doesn’t

have adequate stain blockers in the fiber.

Most carpet comes with manufacturer warranties,

applying only to

owner-occupied

dwellings. These

warranties cover

common food and

household spills, but

exclude bleaches,

pigmented stains,

cationic cleaners, heavy use of dry solvents, disperse dyes

(turmeric – a disperse dye found in mustard), high-

alkaline cleaners and spotters, and more. Never attempt

to interpret a customer’s warranty unless specifically

asked to do so by a mill or manufacturer.

Typically, warranted carpet be cleaned every 6-18

months, depending on usage. Hot water extraction is

preferred. For a list of recommended cleaning methods by

carpet mills, visit the Carpet & Rug Institute website at

www.carpet-rug.com.

Chemical concerns with nylon: Clean with pH of 10

or less, do not use cationic chemicals (both high pH and

cationic or positive charged chemicals will harm the stain

resistance) and do not use optical brighteners which

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fluoresce ultraviolet light and make the carpet look

brighter — but also turn yellow with age.

Olefin (polypropylene)

Olefin fibers are the least

absorbent (actually =

adsorbent, which simply

means it repels water) of all synthetics. For your cleaning process,

this means your cleaning solution will go to the backing of the carpet

faster and create “wicking” on the surface as the carpet dries.

Another problem with olefin: It likes oily soils.

Has a specific gravity less than 1 (water is denser).

Heat sensitive; damage can be caused by temperatures of 250

degrees Fahrenheit and a melting temperature near 325

degrees Fahrenheit. Be careful when dragging furniture as the

heat friction can actually

“melt” the olefin fibers.

May become brittle in

direct sunlight.

Has a tendency to mat

down (less resiliency).

Always solution dyed (with

pigment) and is naturally

stain resistant because of lack of dye sites, and is not affected

by bleaches, including sodium hypochlorite (household chlorine

bleach).

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To prevent wicking, prevacuum, make additional extraction

passes and use air movers.

For effective oily soil removal, use powdered oxygen bleach.

This will help remove many of the smaller oily particles that

build up on the fiber and will also help “bleach” away the grays

or yellows that tend to accumulate on olefin fibers.

Olefin Berbers can be difficult to clean with a standard wand

(extraction tool) as they can “skip” and create “wand chatter”.

Polyester

Polyester (PET) originates from England; it’s normally a staple fiber

that is disperse dyed (same dye that creates the popular yellow

mustard color.)

Many carpet salespeople will tout polyester as resilient as

nylon and “stainproof” — although the fiber is stain resistant, it can

still be stained — and there is the serious problem of matting and

crushing. Polyester should only be installed in a low-traffic area.

It is adsorbent, and wicking problems may occur.

Cleans easily, very colorfast and stain resistant.

Melts at approximately 480 degrees Fahrenheit.

Often made from recycled plastic beverage bottles.

Resistant to bleaches, but color loss still occurs.

You can clean with aggressive chemicals, but not as aggressive

as with olefin. Most polyester goods will have some wear

factor, regardless of age.

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Modified polyester (PTT – now know as
“triexta”)

Beneficial because it has properties and qualities of both

nylon and polyester – it is a newer polyester fiber (PTT) –

corn oil derivative. Please note there are many varieties of

polyester on the market today, as improvements are being

made, but the cleaning procedure will not change from

product to product.

Better resilience than traditional polyester.

Good stain resistance.

No static problems.

Designed for health care and apartments.

Acrylic

Currently has no market share… developed to be a synthetic

replacement for wool. It is now found mainly in furniture fabrics.

It is adsorbent.

It is dyed by either solution or

disperse dye systems.

Dissolves in nitric acid and melts at

450 degrees Fahrenheit.

Will abrade, shade or pool in traffic

areas.

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Cleans well, colorfast, naturally stain resistant, hides soil.

Characteristics of fiber types

Fiber
Nylon

Olefin

Disadvantage

If not stain resistant, nylon
fibers can be stained by acid
dyes, found in many spills

Likes oily spills, melts easily.
When exposed to direct
sunlight, may become brittle
and split easily (more so than
other synthetics)

Polyester

Wool/silk

Cotton/jute/linen

Rayon

Advantage

Dyes easily, very resilient,
easy to clean, hides soils,
accepts protectants* well,
easy to perform spot removal
Olefin is solution dyed, so
there are no dye sites and
thus extremely spot and
stain resistant. Cleans
easily, colorfast* Can be
bleached with .5% or 1%
solution of sodium
hypochlorite
Very colorfast, spot and stain
resistant, cleans easily. Will
lose some color from chlorine
bleach
Wears well due to natural
crimp, hides dirt, easy to
repair color, feels “warm”
and cleans easily
Dyes easily and withstands
bleach. Can be color
repaired.

Inexpensive fiber, very
colorful

Acetate

Acrylic

Imitation silk, at fraction of
cost, low absorbency. Usually
disperse or solution dyed, so
it is colorfast.
Imitation wool. Solution or
dispersed dyed (resists
staining, bleaching) holds
colors well, sun resistant,
imitation wool, cleans easily

Mats and crushes easily,
likes oily spills, abrasion
(wear), pilling, yellowing
with body oils
Costly, easy to stain,
damaged by alkaline agents,
dissolved by bleach spills,
slow to dry
Shrinks, stains easily,
absorbs dirt, subject to
cellulosic browning, slow to
dry because of absorbency.
Absorbent as cotton, slow
drying fiber, low resiliency.
Can shrink every time it is
wet cleaned, weakest when
wet
Stains easily, wear and
chemical sensitive. Dissolves
in acetone (fingernail polish
remover).
Sensitive to heat, loses
dimensional stability. Tend
to yellow or gray in heavy
use areas. Damaged by moist
heat above 200 F.

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Discussion

1. What is the definition of a protein fiber?

2. What is the definition of a cellulosic fiber?

3. In order for there to be “browning”, what must be present in

the carpet? How do you remove “browning”?

4. What is the oldest known carpet fiber?

5. Which fiber is most popular today?

6. Which fiber is the most stain resistant? Why?

7. Which fiber will dissolve in chlorine bleach (sodium

hypochlorite)?

8. Which chemical will dissolve nylon?

9. Which fiber will float on water? Why?

10. What is a negative quality of natural fibers when it comes to

wet cleaning?

11. Which pH should you clean: Wool? Stain resist nylon?

12. What is the outer layer of wool called?

13. Which fiber is the synthetic replacement for wool?

14. Which fiber is fire/flame resistant?

15. Which fiber is commonly made from recycled plastic?

16. What do you call a single fiber strand?

17. What does “BCF” stand for?

18. What is a “spinnerette”?

19. Stain resistant warranties have what limitations?

20. Which cleaning method is recommended for most carpet?

21. Are technicians encouraged to make warranty judgments?

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Fiber identification

Fiber identification tells you exactly what you are working on,

and what is safe and what is not. A true professional will want to

know his “patient”.

There are two basic ways for fiber ID.

The first is burn testing (takes a bit of practice, but is effective for

ID purposes)

This method evaluates several things

1. The color of the flame.

2. The color of the smoke.

3. The odor of the burning fiber.

4. The color and luster of the burned fiber.

5. The shape and hardness of the burned fiber.

Synthetic fibers burn/melt and result in a hard plastic bead (acrylic

is partly an exception as it will crumble), while natural fibers burn

and have an easily-crumbled ash. Since wool and silk are naturally

flame-resistant they do not burn easily.

The second is chemical reaction

This is demonstrated in the following chart. The most common

chemical reaction is formic acid for nylon, bleach for wool and water

for olefin.

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