MYCELIUM MATERIAL, ITS METHOD TO PRODUCE AND USAGE AS LEATHER

SUBSTITUTE

Technical Field of Invention

The present invention relates to the manufacture of mycelium material from agricultural wastes containing cellulose, fungal seed, and plantation medium used as a substitute for leather, for example, but not limited to, in the fashion, accessories, household's appliances and other furniture industries .

Background of Invention

People are already using materials derived from animal skin since long time ago. This material is preferred because of its advantages such as strength, flexibility, durability, and attractive appearance. Animal skin can be applied into various kinds of consumer products, such as clothing, furniture, vehicle interiors, and many other retail products. Global Leather demand continues to increase each year reaching of 93.2 billion USD in 2016 and projected to reach 121.16 billion USD in 2022.

The use of animal skin is not problem-free. Many issues that are often associated with the production of animal skin are related to environmental, health, social issues and others. Animal production used as raw material for leather production, for example, cattle and goats, requires high water, energy, and land, making production of livestock produce large greenhouse gases (CO ₂ and NH ₄ ) . Production of animal skin also requires a large mixture of chemicals (such as chromium salt and dyes from heavy metals) . Trivalent chromium links (cross-link) between collagen molecules in animal skin. However, chromium compounds have other impacts on the environment since it requires a lot of water, has the potential to pollute and also has toxic and carcinogenic properties that can be harmful to human' s health and the environment when it is scattered.

The use of animal skin and fur is also being a concern of the world. Many activistss protest against the use of animal skin and fur because they are considered unethical. With the increasing demand for stopping the use of animal skin, it is necessary to find alternative substitutes. One of the options that is considered more environmentally friendly is synthetic (vegan) leather. This synthetic leather material is made from polyvinyl chloride (PVC) and polyurethane (PU), petroleum- based products.

Even though synthetic leather may provide a solution to the problems of animal skin production processes, PVC-based synthetic materials have not been able to solve environment and health problems. Raw materials derived from petroleum are not sustainable and the process of producing it uses additional chemical compounds such as plasticizer (dibutyl phthalate) to make synthetic leather more elastic. The use of this material has side effects to human' s health because it can interfere with human's hormone signals.

For this, an environmentally friendly leather substitution that has the ability to coat well and has an attractive appearance to consumers is needed. It is expected that leather substitute material derived from fungal mycelium has a shape and texture that resembles animal leather .

The process of producing mycelium material possess relatively small negative impacts to the environment and health. The leather of fungus has a composition of fungal mycelium and cellulose-based raw material agricultural wastes. This leather that dominantly uses natural raw material makes it environment friendly and free of human's health issues. The process of producing materials using technology from fungus eliminates the need to raise livestock on large areas and it turns the production process from 2-3 years long to only 1-2 weeks. The process of producing mycelium material that is currently done only requires agricultural wastes, small amount of water and additional polyethylene glycol (PEG) which is usually used for cosmetic and pharmaceutical products; eliminating the need of hazardous chemicals in the process of producing animal skin, making mycelium produces a relatively small trace/amount of carbon.

The potential for the utilization of mycelium is greater with the development of methods to strengthen mycelium by combination of other structural material layers. Mycelium grows naturally on structural materials made of natural or artificial fibers (plant skin, cotton, gauze, grass fiber, plant fibers, artificial polymer fibers, etc.). Mycelium can grow well between natural fibers microscopically, mycelium and matrix binds perfectly and it increases the strength of the mycelium for multiple amount .

Since conventional leather is made from animals, the size of conventional leather is limited to 30-40 sqf, to replace the use of conventional animal skin leather, we need a leather substitute with larger dimensions and can be mass produced in a short period of time.

Brief Description of Invention

The need for leather material can be provided by mycelium material according to the present invention through a method of manufacture. The material used are agricultural wastes containing cellulose, fungal seed, and growth medium, including, but not limited to bran, lime, saw dust, material structural such as gauze, bark, plant fibers, jute sacks, linen and cotton, and water. Those materials will go through the manufacturing method which consists of the following steps : a. preparing fungus growth medium substrate,

b. mixing fungus growth medium substrate (mixture of agricultural wastes and water) ,

c. putting mixtures of agricultural wastes into sacks as growth medium,

d. sterilizing the medium inside the sacks,

e. cooling the growth medium,

f. putting fungal seeds into growth medium,

g. first incubation,

h. shattering baglog,

i. removing growth medium containing grown fungus seeds into the mould,

j . second incubation,

k. optionally, adding structural material on the surface of growth medium and third incubation,

l. removing thick layers of mycelium on the surface of the medium from growth medium (delamination) ,

m. cleaning the mycelium layer,

n. adding organic or synthetic moisturizers, and

o. letting the mycelium material layer to dry such that the material is ready to be processed further.

Brief Description of Drawings

Figure 1 shows flowchart of the method of producing mycelium material according to the present invention.

Figure 2 shows photographs of products according to the present invention.

Detail Description

In one aspect, the present invention provides a mycelium material with strength, flexibility, good durability, and suitable to substitute conventional leather material. Mycelium material according to the present invention is made from agricultural wastes containing cellulose, fungal seed, and growth medium including but not limited to bran, lime, sawdust, material structural such as gauze, bark, plant fibers, jute sacks, cloth and cotton, and water with agricultural wastes materials composition of 60%-90% and materials other than agricultural waste amount to 10%-40% of the total weight to be prepared.

Agricultural wastes containing cellulose, hereinafter referred to as cellulose wastes, for example without limitation are sugarcane waste, corn waste, leaf waste, husk, straw, fruit skin, tree bark, and palm mesocarp, except of pilel, sawdust, and palm oil cluster. Many of these materials are available around in the form of waste such that it is most preferable if used.

In another aspect, the present invention provides the process of producing mycelium material which consists of the following steps:

a. preparing fungus growth medium substrate,

b. mixing fungus growth medium substrate (mixture of agricultural wastes and water) ,

c. putting mixture of agricultural wastes into sacks to become growth medium,

d. sterilizing growth medium using pressure and heat,

e. cooling the growth medium to ambience temperature (27-30 degree of Celcius),

f. putting fungal seeds into sterilized growth medium,

g. first incubation for 2-4 weeks such that the seeds grows covering the medium,

h. shattering baglog manually or mechanically,

i. removing growth medium containing grown seeds into the mould, j . second incubation for 2-3 days and on the third day reversing the growth medium so that the bottom of the medium will be on the top,

k. optionally, adding structural material on the surface of growth medium and third incubation for 5-6 days while surface of mycelium is pressed gently using bare hand or a planar,

l. removing thick layers of mycelium on the surface of the medium from growth medium (delamination) ,

m. cleaning the mycelium layers from the remnants of growth medium,

n. providing preservation treatment (including salting, boiling)

o. adding organic or synthetic moisturizer in the whole upper and lower parts, and

p. letting the mycelium layers to dry thus said material is ready to be processed further.

The process of producing mycelium material is described in more detail below.

A mixture of agricultural waste is prepared by drying and shattering processes. Mixing the agricultural wastes is carried out with a predetermined composition of formulations, agricultural wastes material is 60%-90% and materials other than agricultural wastes are 10%-40% of the total weight to be prepared. Formulations of agricultural waste have a complete composition for the growth of fungal seeds, which contain carbon sources, nitrogen sources and phosphate sources. Required water in medium formulations ranges from 60-75% for the fungus to grow well. The stirring process performed on a mixture of growth medium so that the medium becomes homogeneous. Homogeneous growth medium is fed into a packaging container and ready for sterilization.

The sterilization of the medium uses pressure and heat, preferably using autoclave 121 °C for 100-120 minutes then pulled-out. Since the sterilized medium temperature is quite high after being pulled-out from autoclave (100-90°C), the medium need to be located in the clean room (for 12-24 hours) until the temperature drops to ambience temperature (27-30°C) . Growth medium temperature need to be lowered so that it can be inoculated with fungal seeds .

Further process is putting the fungal seeds into sterilized growth medium of 5-10% of the weight of the growth medium such that the first incubation occurs so that the seeds grow covering the medium for 2-4 weeks. The medium seems fully covered by white fungal mycelium in all parts .

Furthermore, shattering baglog manually or mechanically, preferably in the form of an aggregates of 1-10 cm in diameter. The benefit is in shorter growth duration hence avoiding contaminants threat. If the growth period is excessive, undesired fungus will grow. The diameter refers to the longest side of the aggregate baglog in irregular shapes.

The contents of growth medium are removed from the sack, shattered, and put into the mould. The maximum mould thickness is about 15 cm. At this time, it can be conducted simultaneously or afterwards, pressing until it is sufficiently solid in the whole parts evenly to the desired size. Pressing can be conducted by bare hand or a planar.

The contents of the medium are provided the second incubation treatment for 2-3 days and reverse the growth medium at the third day such that the bottom of the medium will be on the top. The purpose is for the fungus to grow optimally on both sides .

Optionally, a process of adding structural material to the surface of growth medium can be carried out. This structural material serves to increase the strength of the leather or to provide a desired certain texture by consumers. Examples of structural materials that can be used without limitation are bark, cotton, gauze, grass fiber, plant fibers, artificial fiber and polymers.

The addition of structural material is provided by placing an additional layer of material on the surface of said mycelium. Fungus will integrate with said additional layer so that produced the desired layer. The purpose is to produce a mycelium with certain appearance and physical properties.

Furthermore, if an optional step is carried out in the process of adding structural material, then duration of the third incubation is 5-6 days until the thick growing mycelium fills the whole surface parts of the growth medium. At this step, in the whole days, the mycelium on the top surface of the medium is suppressed gently such that the mycelium grows evenly. Pressing can be conducted with bare hand or a planar.

Delamination of the mycelium leather is carried out if the mycelium layers has a maximum age of 14 days since the seeds are fed into the growth medium. At this age, the fungus grows bushy on surface of the growth medium. The outer layer of the outer mycelium is delaminated so that it is separated from growth medium. This process is known as delamination. The delamination process must be conducted gently to avoid any damage on mycelium to be harvested.

In the delamination process, there is almost often that growth medium is attracted to the bottom of the mycelium. For example, this is identical to the process of skinning animal skin which almost often leaves fat and flesh that is also taken on the skin to be separated. So that the skin of harvested mycelium must be cleaned gently (to avoid any damage on surface of the skin) by using a cleaning tool (such as a brush) , to clean the growth medium (residual agricultural wastes) which is raised at the bottom of mycelium layers.

The delamination result needs to be treated by preservation which includes salting and boiling. Salting is conducted by sprinkling salt to the whole surface of mycelium and boiling is conducted by heating the leather of mycelium in the water until it is boiled. The purpose of this preservation is to avoid the mycelium being rotten in which characterized by the release of a foul aroma from the leather of mycelium and the presence of mucus on the surface.

Furthermore, moisturizers are provided to maintain the moisture of the mycelium skin to be used. After the preservation, mycelium is ready for moisturizing process. Thinned organic moisturizer is rubbed to whole upperpart and lower part surface of mycelium. Then the mycelium is left for 30-60 minutes. The mycelium can be dried by aerating until dried into mycelium material. The material is ready for further process.

In another aspect, the present invention provides the use of mycelium material produced by the above method as a substitute for leather, for example without limitation, in the fields of fashion, furniture, and other accessories.

From the results of one of the tests, we obtain data on the ratio of maximum elasticity and pressure that can be borne by mycelium material according to the present invention with another materials as mentioned in Table 1.

Table 1. Result of Elasticity and Maximum Pressure Test

Table 1 shows that elasticity of mycelium material is up to 70% from leather, and far better than synthetic leather.

From another test, we obtained the comparison of production cost for mycelium material of present invention to other materials as mentioned in Table 2.

Table 2. Total Production cost (HPP) Comparison Per Square feet

Table 2 shows that cost of producing mycelium material is cheaper than leather, close to half of the leather's cost.

From Table 1 and Table 2, it can be seen that the mycelium material according to the present invention has characteristics of elasticity close to leather with lowest production cost which is suitable as a substitute for leather. Some other advantages of the mycelium material according to the present invention compared to leather are:

- raw materials for the production process are easily available and inexpensive since they derived from various agricultural wastes;

- raw materials and natural processes such that they are clean and environmentally friendly;

- the whole process uses much less energy and water than conventional animal skin; - it has relatively less impact to environment compared to animal skin, because it produces very small amount of greenhouse gases (C0 ₂ or NH ₄₎ ;

- it does not require a large place for production;

- the production process is relatively short (1-2 weeks) compared to conventional cattle skin (2-3 years);

- The shapes and sizes are flexible and can be adjusted according to the consumer' s demand (possible in the large size) ;

- appearance and strength are identical to animal skin and adjustable according to their physical character (thickness and pattern) ;

- possible to be applied widely for various applications similar to conventional animal skin;

- coloring and preservation process use a lot of natural materials no need artificial chemicals which are not environmentally friendly and toxic are being used;

- it uses raw materials and natural process, such that they can be disposed to the environment and degraded naturally; unlike synthetic leather containing plastic and synthetic preservatives .

The present invention can be utilized to produce mycelium material with unlimited size. Unlike the animal's skin (cattle, goats, reptiles) that have limited size of animals that are a source of leather raw material (30-40 sqf maximum), this material can be made with sizes that are theoretically unlimited. The only factor that limit the size of mycelium material are only the size of the mould and structure used so that the material can be made to the smallest size to the largest size (for example, more than 500 sqf) and mass produced in a short time. Therefore, the present invention complies with industrial applicability. The used terms refer to the terms commonly used in such field or sector. The difference of interpretation shall be referred to common understanding in the art.