HomeProducts ≫ What's Nonwoven?

What's Nonwoven?

What's Nonwoven?

Many of the visitors of this website might think "What is nonwoven?" The answer is, literally, "fabrics that are not woven." However, we don't have an opportunity to hear this term in our daily life.

Nonwovens and Paper

Nonwovens and Paper

Before explaining what nonwovens are, we should understand what "paper" is.
Some may think "Why paper? We are discussing fabrics!" because generally people have in mind the general fabrics of, for example, the clothing they wear; fabrics in a general sense are sheet-shaped materials made by weaving yarn.

What does "yarn" mean here? The answer is a thing that is made by stretching and twisting a fiber. Types of fibers vary from plant fibers to animal fibers, e.g. wool, and synthetic fibers, e.g. polyester.
On the other hand, paper is a sheet-shaped material made by dispersing fibers in water, and entangling them through processes such as dehydration and drying. Fibers primarily used for papermaking are plant fibers.

That's right. Both paper and fabrics are sheet-shaped matters produced by processing fibers although there are differences in fiber types and processes.

Generally, thread-shaped fibers woven to form a sheet are called a fabric and unprocessed fibers woven to form a sheet are called paper.
Today, not only plant fibers but also synthetic and metal fibers can be used to make paper due to the advancement of technologies. Given that, people started to call sheets made from plant fibers "paper" and sheets made from synthetic fibers and/or metal fibers as "nonwovens."

History of Nonwovens

History of Nonwovens

Before the history of nonwovens, the history of paper should be discussed. Paper has a long history. According to the currently predominant theory, paper already existed in the second century B.C. and a Chinese inventor Ts'ai Lung consolidated and improved the existing papermaking technologies around 105 B.C. The methods are said to be introduced from Goguryeo into Japan in 610.

The history of industrial nonwovens is believed to start in the 1920's when a German felt trading company solidified flock and wool by glue as a substitute for felt. Felt is a collective term for sheet-shaped goods produced by collecting and compressing animal hair and this is also one kind of nonwovens. Felt has a longer history than paper and archaeologists believe the oldest felt existed around the fifth century B.C.

In Japan, the production of wetlaid nonwovens started in the 1950's. Several years later, we, Hirose Paper Mfg, began production of wetlaid nonwovens, which was the start of the full-fledged era of nonwovens.

Types of Nonwovens and Papers

Types of Nonwovens and Papers

There are two major types of paper: Western paper and Japanese paper. Examples of Western paper are newspaper and copier paper, i.e. machine-made paper. They can be found anywhere in our lives. Japanese paper is hand-made paper; presumably many Japanese people have experience making paper. For your information, Kochi's signature Japanese paper is Tosa Washi.

The major difference between Western paper and Japanese paper is their raw materials.
Raw materials of Western paper are primarily wood fibers of broad-leaved and needle-leaved trees, which are characterized by relatively short length (1-5mm).
Raw materials of Japanese paper are bast fibers of ramie, mulberry and paperbush, etc. which are characterized by relatively long length (15-25mm). Further, viscous liquid made from plant roots, called "Neri," is used to bind the fibers together.

On the other hand, there are 2 types of nonwovens: drylaid and wetlaid. The major difference between them is their manufacturing methods.
Drylaid nonwovens are manufactured by forming fibers into a webbed shape by using a machine called a "card" and binding fibers by punching them with a needle called a "needle punch" or melting them by heat. They are characterized by cloth-like texture and are often used for clothing and sanitary products.
The manufacturing method of wetlaid nonwovens is the same as traditional papermaking: mixing water and fibers, straining them on a net and dehydrating by compression and heating. The texture is bamboo-like and the sheets are uniform. They are often used for medical and industrial applications.
Appearances of wetlaid nonwovens are similar to Western paper (with some exceptions though).

Nonwovens near You

Many of you may think "I've never seen any nonwovens around me!"
In fact, however, they are unexpectedly close to you.

Below are some examples by applications.

◯Healthcare Compress and gauze
◯Clothing Interlining cloth and bra cups
◯Sanitary materials Chemical wiper, feminine hygiene products, masks and paper diapers
◯Construction materials Carpet base materials, acoustic absorption boards and A/C filters
◯Automobiles Interior materials, air elements, cabin filters and acoustic/vibration insulators
◯Industries Battery separators, double-sided tape and industrial wipers
◯Agriculture and civil engineering Drainage sheets for greening and seeding sheets
◯Kitchen utensils Coffee filters, sink draining bags, tea bags and paper towels
湿式不織布 電池用セパレーター 湿式不織布 コーヒーフィルター 湿式不織布 オフセット印刷用不織布
Battery separators Coffee filters Nonwovens for offset printing

What do you think? They are around you after all, aren’t they?
Their applications are also diverse.
Especially, it might be surprising for you that they are even used in batteries. So how are they used in them? Nonwovens are in there being impregnated with electrolytic solution. The mechanism is that batteries generate electricity through chemical reactions of electrolytes in the solution. That's awesome, isn't it?

As you can see, there are nonwovens all around you!