APPAREL VIEWS / MAY 201142

SPF is a kind of regenerative plant fibre. SPF is the

only botanic protein fibre in the world, a newly

born guard to mankind's skin. This fibre appears from

soybean a plant which has enormous source and

affluent in nutrition. As it contains 18 amino acids

beneficial to the human body, and added anti-bacterial

elements, SPF offers a protective function to the skin.

SPF has been praised locally and internationally by

industry expert as the healthy and comfortable fibre

of 21st Century. The main component of soybean fibre

is it possesses the superiorities of many natural fibres

and synthesised ones and it is quite similar to those

of cashmere and silk, featuring fine denier, low density

and good tenacity and elongation. The resulting fabric

can give cashmere-like hand touch, silk-like luster,

cotton-like moisture conduction and wool-like warm

retentiveness. The invention of SPF is the contribution

of mankind to the protection of natural rare minerals,

the protection of resources, the care of the

environment and the consideration of the global

balance. It is an active fibre, a new green textile fibre.

SPF is an advanced textile fibre. It is also known as

"vegetable cashmere" or "soy silk." It is made from

the soybean cake after oiling by new bioengineering

technology. Firstly, the spherical protein is distilled

from the soybean cake and refined. Secondly, under

the functioning of auxiliary agent and biological

enzyme, the space structure of spherical protein

changes, and then protein spinning liquid is confected

by adding high polymers, and then thirdly, after the

liquid is cooked, the 0.9~3.0dtex fibre is produced by

wet spinning, and stabilised by acetalising, and finally

cut into short staples after curling and thermoforming.

SPF is praised as the health, comfortable and green

fibre of the new century. Its major material is soybean

protein from the farmers, massive in quantity and

inexpensive in price, and using it will not cause the

predatory development on the resources but is helpful

to resources' recovery and redevelopment. The

production of SPF will not bring pollution to the

environment, as the accessory and auxiliary agent

used are not poisonous, while the residue after the

protein extracted can be still used as feed. SPF has

not only the superiorities of the natural fibres but also

the physical properties of synthetic ones. SPF meets

the people's demand of comfortable and beautiful

wearing and also conforms to the trend of easy care.

It is the potential material for middle and high class

clothing in textile industry.

History of SPF

In 1932-33 the Ford Motor Company spent millions of

dollars on soybean research. Henry Ford promoted

the soybean, helping to develop uses for it both in

food and in industrial products. By 1935 every Ford

car had soy involved in its manufacture. For example,

soybean oil was used to paint the automobiles as

well as fluid for shock absorbers.

In 1935, Ford hired chemists Robert Boyer and Frank

Calvert to produce artificial silk. They succeeded in

making a textile fibre of spun soy protein fibres,

hardened or tanned in a formaldehyde bath, which

was given the name Azlon by the Federal Trade

Commission. The production started in 1939 and fibres

were used to make upholstery for motorcars. It was

also usable in the making of suits, felt hats, necktie

and overcoats.

Though pilot production of Azlon reached 5,000 pounds

per day in 1940, it never reached the commercial

market. Then the production was taken over by the

Drackett Products Co. and a new plant was set up in

1949. After 10 years of hard work of Li Guanqi's as

well as the contribution and assistance of many other

departments and organisation, soybean fibre has

come into birth and its industrialisation started.

China began the commercial production of soybean

fibre in 2001 in line with the call from China National

Textile & Apparel Council (CNTAC). According rough

statistics, over 500 textile mills have been concerned

with the development and application of soybean fibre.

APPAREL VIEWS / MAY 2011 43

Microscopic features

Vertical shear of SPF is irregular and has moisture

absorbing grooves. When lengthwise fibres are

examined microscopically, longitudinal lines called

striations are seen. In cross section it appears

dumbbell shaped and has Island-in-a sea structure.

Physical parameters of soybean fibre

No. Items Unit Figure

1 Moisture regain Per cent 8.6

2 Friction force F/gf 33.4

3 Breaking strength CN/dtex =>2.5

4 Drape coefficient Per cent 7

5 Antistatic property g/cm2 10.33

6 Elastic recover Per cent 55.4

7 Crimp ratio Per cent 1.65

Characteristics of SPF

• Cashmere feel: The fabric made of SPF is soft,

smooth, light. It has cashmere feel, but smoother

than cashmere; it is as comfortable to the skin as

human's second skin

• Dry and comfortable: The moisture absorption of

SPF is similar to that of cotton fibre, but its

ventilation is more superior to of cotton. Knitting

fabric of SPF has soft, smooth and light handle which

is the same as that of fabrics made from silk blended

with cashmere

• Luxurious appearance: SPF fabric has joyful silky

lustre with perfect drape and elegant; fabrics of

yarn in high count has fine and clear texture and is

classical shirting

Vertical shear of SPF underElectron microscope

Cross section of SPF underElectron microscope

Property SPF Cotton Viscose Silk Wool

Breaking strength 3.8-4.0 1.9-3.1 1.5-2.0 2.6-3.5 0.9-1.6

(CN/dtex) 2.5-3.0 2.2-3.1 0.7-1.1 1.9-2.5 0.7-1.3

Dry breaking 18-21 7-10 18-24 14-25 25-35

extension (Per cent)

Initial modulus (kg/mm2) 700-1300 850-1200 850-1150 650-1250

Loop strength (Per cent) 75-85 70 30-65 60-80

Knot strength (Per cent) 85 92-100 45-60 80-85

Moisture regain (Per cent) 8.6 9.0 13.0 11.0 14-16

Density (g/cm3) 1.29 1.50-1.54 1.46-1.52 1.34-1.38 1.33

Heat endurance Yellowing and Becoming brown Strength Keep stable when (Good)

tackifing at about after long time down after long time temperature

120° C processing at 150° C processing at 150° C <=148° C

(Bad) (Excellent) (Good) (Good)

Moth resistance Excellent Excellent Bad Bad

Fungus resistance Excellent Bad Excellent Excellent

Alkali resistance At general level Excellent Excellent Good Bad

Acid resistance Excellent Bad Bad Excellent Excellent

Ultraviolet resistance Good At the general level Bad Bad Bad

Wet

Dry

Physical parameters compared with other fibres

• Good colour fastness: The original colour of SPF is

ivory like tussah colour. It can be dyed by acid dyes

and active dyes especially the colour is quite fresh

and lustrous with the later dyes while quite stable

in the sunshine and perspiration. Compared with

silk products, the problem of freshness of colour

and stability of dyeing

• Function of health: SPF possesses many amino

acids necessary to human's body, so this sole

botanic protein fibre has the function of health that

no other fibre processes. Meeting people's skin,

the amino acid in soybean protein can activate the

collagen protein in the skin, resist tickling and

evaporate the skin. Bacteria resistant elements

are integrated in fibre's molecule chain, which

makes the fabrics keep the property of resisting

coli bacillus, staphylococcus aureus and candida

albicans permanently, this avoids the shortcoming

of not permanent effect when the anti-bacteria

function is added to the yarn when finishing

• Good physical property: Breaking strength of the

single SPF is over 3.0CNdtex, which is higher than

that of wool, cotton and silk and only lower than

that of polyester fibre of high intension. By now,

1.27dtex fibre can be spun into 6dtex yarn with

high quality, which can be used for high-quality and

high-density fabrics. Also, fabric of SPF has

outstanding anti-crease, easy-wash and fast-dry

property

• Anti-ultraviolet: Its anti-ultraviolet property is

superior to cotton fibre, much more superior to

viscose and silk. The absorptive of ultraviolet

radiation could reach upto 99.7 per cent

• Far infrared function: The emissivity of far-infrared

could reach upto 87 per cent, have the function of

heat-effect, promoting micro circulation of skin and

enforcing the immunity etc.

• Skin evaporation: Its amino acid can activate the

collagen protein in the skin, resist tickling and

evaporate the skin

• Antibacterial: Soybean protein fibre has

antibacterial properties that resist colibacillus,

staphylococcus aurous and candica albicans.

Fabrics made from soy protein fibre and linen or

other fibres are ideal for functional underwear and

summer wear

Blending of SPF

SPF can be blended well with other fibres to give

more features.

1) With cashmere: Blended with cashmere fibre, SPF

enhances the hand as well as lowers the

manufacturing cost of cashmere products. Gives

superior natural softness, lustres and comfort, as

well as anti-pilling and drape properties along with

intimacy to skin, easy care. E.g. suitable for

cashmere sweater, shawl and coat.

2) With mercerised wool: Blend gives a kind of knit

fabric quite similar to that of cashmere with colour

more abundant and better mercerised effect.

Produces excellent results taking advantage of

both fibres, the lustrous, soft hand and strength of

soybean fibre, and the elasticity and heat-retaining

properties of wool. As its shrinkage is less, it is

easier to wash and preserve. Spinning of high-

count yarn is possible. E.g. suitable for wool

sweater, interlock underwear and blanket

3) With silk: Combination has not only lustre and

elegance of silk but also a good draping. At the

same time, provides a solution to problems of

silk, such as poor resistance to staining from

perspiration and water, sticky to skin being wet,

poor light fastness and moisture permeability.

Higher quality can be achieved at a lower cost.

E.g. suitable for printing silk, knitting underwear,

sleepwear, shirts and evening dress

4) With combed cotton: Compared to cotton fabrics,

it has softer hand, lustre, better moisture absorption

and ventilation, quick dry, better bacteria

resistance, more comfort for wearing. Blend also

enhances the drape properties of cotton. E.g.

suitable for men's and women's underwear, T-shirt,

infant's wear, towel and beddings

5) With elastic fibre: Adding a small portion of

elastic fibre makes fabrics more elastic and easier

for washing and caring. It is quite active and

charming

6) With polyester and other synthetic fibres: The

blends raise the properties of comfort, beauty

and wrinkling resistance. E.g. suitable for spring

and summer fashion apparels, underwear, shirt

and sportswear

1. Soybean Plant

2. Soybean cakes

3. Raw Material

4.SPF+PVA

5.Wet spinning

6. SPF

APPAREL VIEWS / MAY 201144

Applications of soybean fibre

Yarn: Spinning methods have already been

established for 100 per cent soybean fibre, its blends

with natural (cotton, linen, wool, cashmere and silk)

and chemical (modified polyester, viscose, tencel,

polynosic etc.) fibres, and used in plants dealing with

cotton, silk and wool. Production of 100 per cent

soybean fibre yarns in the range of 21S-80S and

blended yarns (28/72, 30/70, 45/55, 60/40, 70/30, 85/

15 etc.) is possible.

Knit fabric: Soybean protein contained in the fibre

makes a superior, soft hand endowed with both

moisture absorbency and permeability, which makes

best application in knits and innerwear. Finished with

an anti-bacterial agent, health-care functionalities are

also given. It has great potential in its use in high-

grade knits and innerwear.

Woven fabric: Weaves made of soybean fibre blends

with other natural or chemical fibres have so far been

used in shirting and home textiles. A series of such

products, too, has already been developed. Their

special feature is the lustre and soft hand found in

silk. Their economic effects are extremely high.

SPF are soft and smooth as well as absorbent it is

ideal for products that are worn close to the skin such

as underwear, sleepwear, sportswear and children's

and infant's clothes, bed sheets, towels and blankets.

Undergarments: The undergarment made by SPF and

spandex, has incomparable and unimaginable

softness and comfortableness. Wearer’s skin enjoys

the pleasing breath after wearing SPF fabric, easy

stretch and fine caring especially “skin on skin”

feeling.

Baby wear: Eco-friendly soybean baby clothing offers

many benefits to baby. The breathability, warmth and

comfort are outstanding.

Skirt: SPF has lustre of silk which is joyful and an

excellent drape which makes the fabric elegant;

fabrics of yarn with high count has fine and clear

appearance and is ideal for top-level shirt.

Advantages

• Luxurious appearance

• Fabric is soft, smooth and light

• Naturally has the light, smooth, soft feel of cashmere

• Light-reflecting properties gives the lustre of silk

• Elegant draping abilities

• Anti-wrinkle

• Provides better ventilation than cotton

• Higher breaking strength than wool, cotton or silk

• Good absorbency - moisture absorption equal to

cotton

• Warmth retention like wool

• No shrinkage

• Antibacterial qualities

• Colour-fast and has good dyeing properties

• Sunlight resistant

• Perspiration fastness

• Dries quickly and easily

• Very lightweight - perfect for undergarments or

summer wear and excellent for kids clothes

• Natural golden colour

Disadvantages

• Due to the low frictional coefficient, low crimp

number and low crimp stability of soybean fibre,

the soybean fabric is easy to fuzz

Caring for soybean clothes

• Soy clothing is easy wash and dries quickly

• Hand wash or gently cycle in cold water

• Get shrink in boiling water

• No dry cleaning is necessary

• Avoid chlorine bleaches

• Either air dry, or tumble dry with no heat

• Fast drying fibre

• Can be ironed on a low setting without steam

• High heat may damages the fabric

• Like many other fabrics, dark coloured soy materials

can bleed when laundered. Wash these separately,

or use a dye catcher sheet

• Hang or lay flat to dry

Environmental benefits of soybean

SPF fabrics are considered green. These consist of

by-products left over from processing tofu, soybean

oil, and other soy foods. The raw materials’ being a

natural product available in abundance and recyclable

there is no waste of resources. All auxiliary materials

and agents used in the production of SPF are harmless

to nature, and most auxiliaries used and even

unfinished products are recyclable. The bean dregs,

too, after having their protein extracted can be used

as fodder. SPF is a kind of environmentally protecting

product which does not harm to the environment,

atmosphere, water and human body during its process

of production.

Conclusion

The invention of SPF is the contribution of mankind to

the protection of natural rare minerals, the protection

of resources, the care of the environment and the

consideration of the global balance. SPF produces a

positive effect on human skin improving its overall

energetic balance. Some of the healthy organic

components prevent early skin aging. SPF offers a

number of great properties for both the wearer and

the environment. It is a renewable natural resource

that is bio-degradable and eco-friendly.

SPF can fill up the vacancy in textile material

development of our country as a big textile-producing

country. It will inevitably stimulate the new product

development in the field of cotton, wool and spun silk

spinning, and bring the textile corporations new

development opportunity

Tee-shirt in ‘Luxury soy’ 55 per cent soy, 40 per centcotton, 5 per cent Lycra

By Vasant R Kothari, Assistant Professor,NIFT, Bangalore & Pallavi Jain, MFTech

(Student), NIFT Bangalore (Author can becontacted @ www.vasantkothari.com)

2(x)ist's recently released soy collection features severalstyles of briefs and a T-shirt made with 95 per cent soy-based fabric (the rest is nylon).