WO2015033481A1

WO2015033481A1 - Process for manufacturing carbonized cloth

Info

Publication number: WO2015033481A1
Application number: PCT/JP2013/079795
Authority: WO
Inventors: 道宇可児; 基弘上野
Original assignee: Kani Dou
Priority date: 2013-09-05
Filing date: 2013-11-01
Publication date: 2015-03-12
Also published as: JP2015052175A; EP3042988A4; EP3042988A1; JP6217040B2; US20160222550A1

Abstract

The present invention addresses the problem of providing a process for manufacturing a carbonized cloth which exhibits conductivity and such softness and strength that the cloth can withstand processing. A process for manufacturing a carbonized cloth by heating a cellulose-containing cloth in a furnace, comprising: a cloth-disposing step for disposing the cloth in a furnace; a first temperature-rising step for providing an inert atmosphere to at least a region which is in the inside of the furnace and in which the cloth is disposed, and rising the internal temperature of the furnace to a level that is close to and lower than the temperature at which the cloth is carbonized; a second temperature-rising step for providing, after the first temperature-rising step, an atmosphere which is more reductive than the inert atmosphere in the first temperature-rising step to at least the region which is in the inside of the furnace and in which the cloth is disposed, and rising the internal temperature of the furnace to 1200 to 1400ºC; a keeping step for keeping, for a prescribed time, the internal temperature which has been risen to 1200 to 1400ºC in the second temperature-rising step; a temperature-lowering step for lowering gradually the internal temperature of the furnace after the lapse of the prescribed time; and a furnace-opening step for opening the furnace after the internal temperature of the furnace has lowered to about 100ºC or lower in the temperature-lowering step.

Description

Carbonized fabric manufacturing method

The present invention relates to a carbonized cloth manufacturing method for manufacturing a carbonized cloth by heating a cloth containing cellulose in a furnace.

Charcoal obtained by carbonizing organic matter is used as a heating element by obtaining electrical conductivity, or as an adsorbent due to its large surface area and high porosity, and is used in various fields. . In particular, the carbonized cloth obtained by carbonizing the cloth is suitable as a planar heating element such as a floor heating device or a snow melting device.

Generally, carbonized cloth can be manufactured by heating in an inert atmosphere, but if carbonization is not sufficient, conductivity may not be obtained.

JP 2009-129807 A

Therefore, an object of the present invention is to provide a method for manufacturing a carbonized cloth that can be a highly efficient heating element that generates heat instantaneously after power is turned on.

The following inventions are provided as means for solving the above problems. That is, a carbonized cloth manufacturing method for manufacturing a carbonized cloth by heating a cloth containing cellulose in a furnace, wherein the cloth arranging step for arranging the cloth in the furnace and at least the cloth arranging area in the furnace are inactive. A first temperature raising step for raising the temperature to a temperature before the cloth is carbonized, and after the first temperature raising step, at least the cloth arrangement region in the furnace is relative to at least the inert atmosphere in the first temperature raising step. A second heating step for raising the temperature to 1200 ° C. to 1400 ° C., a maintaining step for maintaining the furnace temperature that has reached 1200 ° C. to 1400 ° C. for a predetermined time by the second heating step, A carbonized fabric manufacturing method comprising: a temperature lowering step for gradually lowering the furnace temperature after a predetermined time has elapsed; and a furnace opening step for opening the furnace after the temperature inside the furnace becomes approximately 100 ° C. or lower by the temperature lowering step. Subjected to.

Further, in the carbonized cloth manufacturing method, the cloth provides a carbonized cloth manufacturing method using cotton as a raw material. In the maintenance step, a carbonized cloth manufacturing method is provided in which the predetermined time is approximately 1 to 2 hours. Moreover, the carbonized cloth manufacturing method in which the time spent for the temperature lowering step is 20 hours or more is provided. Moreover, the said furnace opening step provides the carbonized cloth manufacturing method which opens and closes a furnace intermittently so that the temperature in a furnace may not fall rapidly.

According to the present invention, it is possible to provide a method for manufacturing a carbonized fabric that can be a highly efficient heating element that generates heat instantaneously after power is turned on.

The flowchart which shows the flow of each step which comprises the manufacturing method of this embodiment. Photograph by FE-SEM of carbonized fabric manufactured by the manufacturing method of this embodiment Photograph by FE-SEM of carbonized fabric manufactured by the manufacturing method of this embodiment Photograph by FE-SEM of carbonized fabric manufactured by the manufacturing method of this embodiment Photograph by FE-SEM of carbonized fabric manufactured by the manufacturing method of this embodiment Photograph by FE-SEM of carbonized fabric manufactured by the manufacturing method of this embodiment Photograph by FE-SEM of carbonized fabric manufactured by the manufacturing method of this embodiment Raman spectroscopic analysis result for carbonized fabric manufactured by the manufacturing method of the present embodiment The conceptual diagram which shows the application example of the carbonization cloth manufactured by the manufacturing method of this embodiment The conceptual diagram which shows the application example of the carbonization cloth manufactured by the manufacturing method of this embodiment

Embodiments of the present invention will be described below. In addition, this invention should not be limited to these embodiments at all, and can be implemented in various modes without departing from the gist thereof.
<Summary of Embodiment>

In the carbonized fabric manufacturing method of the present embodiment, the temperature is raised in an inert atmosphere to a temperature before carbonization, and then the temperature is further raised to 1200 ° C. to 1400 ° C. while maintaining the inside of the furnace in a reducing atmosphere, and is maintained for a predetermined time. . Such a manufacturing method makes it possible to manufacture a carbonized fabric that can be a highly efficient heating element that generates heat instantaneously after power is turned on.
<Embodiment Configuration>

FIG. 1 is a flowchart showing the flow of each step constituting the carbonized fabric manufacturing method of the present embodiment. This embodiment is a carbonized cloth manufacturing method for manufacturing a carbonized cloth by heating a cloth containing cellulose in a furnace. As shown in the figure, a “fabric placement step” (S0101), Temperature step ”(S0102),“ second temperature raising step ”(S0103),“ maintenance step ”(S0104),“ temperature lowering step ”(S0105), and“ furnace opening step ”(S0106). It is a waste.

Cloth of this embodiment contains cellulose. For example, it is made by weaving or weaving vegetable cellulose fibers such as cotton, hemp, silk, bamboo, ridges, and wood pulp. Moreover, the cloth which consists of a recycled fiber which melt | dissolves a natural fiber or polymer once, and makes it a fiber may be sufficient. Moreover, it is good also as a nonwoven fabric as well as the thing knitted or woven. Further, the cloth is not necessarily limited to a planar shape, and may be a string shape.

“Cloth placement step” (S0101) is a step of placing the cloth in the furnace. The furnace is only required to be able to control the temperature in the furnace, shut off the outside air, and control so that the atmosphere in the furnace can be an inert atmosphere or a reducing atmosphere.

The form of the cloth arranged in the furnace is arranged by laminating cloths cut according to the size of the arrangement area, arranged in multiple folded without cutting, or in a wound state Or may be arranged.

The region in the furnace where the cloth is disposed is not particularly limited, but it is preferably disposed in a region where the above temperature control and in-furnace control are satisfactorily achieved. That is, when an inert gas is introduced into the furnace, if there may be a region where the inert gas is difficult to reach, it is not preferable to place a cloth in such a region.

In addition, when carbon monoxide is generated by incomplete combustion of the burner to create a reducing atmosphere in the furnace, it is arranged so that the combustion flame does not directly hit the cloth, or with a refractory metal, etc. It is preferable to arrange the cloth so as to be isolated from the combustion flame.

The “first temperature raising step” (S0102) is a step of raising the temperature to a temperature before the cloth is carbonized with an inert atmosphere in at least the cloth arrangement region in the furnace. The temperature at which the cloth is carbonized varies depending on the material and composition of the cloth, but is generally about 300 ° C to 500 ° C. Depending on the temperature at which the disposed fabric is carbonized, the fabric placement region is made an inert atmosphere until such temperature is reached. Examples of the inert gas for making the inert atmosphere include nitrogen gas, helium gas, argon gas, neon gas, and the like. By raising the temperature in an inert atmosphere, carbonization is promoted without burning the cloth. Note that the time spent for the first temperature raising step depends on various conditions such as the material and amount of the cloth and the volume of the furnace, and is, for example, about 0.5 to 3 hours. When the temperature is raised in an excessively short time, there is a possibility that the fibers constituting the cloth may break or split due to a sudden volume change.

In the “second heating step” (S0103), after the first heating step, at least the cloth arrangement region in the furnace is made a reducing atmosphere relatively to the inert atmosphere in at least the first heating step, 1200 ° C. This is a step of raising the temperature to ˜1400 ° C.

“To make the reducing atmosphere relatively less than the inert atmosphere in the first temperature raising step” is to make the reducing atmosphere contain more in the furnace than the inert atmosphere. By making the inside of the furnace a relatively reducing atmosphere, carbonization is promoted by the oxygen scavenging action on the cloth, and impurities are removed to obtain a carbonized cloth with high carbon purity.

Examples of the reducing gas for making the reducing atmosphere include carbon monoxide gas, hydrogen sulfide gas, sulfur dioxide gas, hydrogen gas, and formaldehyde gas. Introducing the reducing gas into the furnace may introduce these gases directly, or install a burner using a fuel gas such as propane or butane in the furnace and incompletely combust it. A gas may be generated. Further, reducing metal particles may be exposed in the furnace by sputtering or vapor deposition, and the inside of the furnace may be made a reducing atmosphere by reaction of these metal particles. Examples of such metals include lithium, cesium, rubidium, potassium, barium, strontium, calcium, sodium, magnesium, thorium, beryllium, aluminum, titanium, zirconium, manganese, tantalum, zinc, chromium, iron, cadmium, cobalt, Nickel, tin, zinc and the like can be used. In addition, each said process for setting it as a reducing atmosphere may be performed collectively, and you may make it perform each process in steps. Further, the fuel gas of the burner is not limited to the gas having the purity of propane or methane of 100%, but may be city gas to which an odorant such as thiol is added.

In the carbonization of cloth, the higher the carbonization temperature, the more the carbon crystallization proceeds. This crystallization is partial, but this improves the conductivity. On the other hand, since the embrittlement progresses as the carbonization is performed at a high temperature, the shape of the cloth may be lost. Therefore, the ultimate temperature in the second temperature raising step is as described above. That is, when the ultimate temperature is below 1200 ° C., it may be difficult to obtain desired conductivity. In addition, when the ultimate temperature exceeds 1400 ° C., embrittlement may progress excessively.

The time taken to reach the temperature reached in the second temperature raising step can be appropriately determined according to the material and amount of the carbonized cloth, the furnace volume, etc., but is preferably about 1 to 5 hours, for example. When the temperature is raised in an excessively short time, there is a possibility that the fibers constituting the cloth may break or split due to a sudden volume change. On the other hand, even if the temperature is increased by spending too much time, the effect is not so much, and time and energy may be wasted.

The “maintenance step” (S0104) is a step of maintaining the furnace temperature that has reached 1200 ° C. to 1400 ° C. for the predetermined time by the second temperature raising step. Carbonization is completed in the maintenance step. The time spent for this step depends on various conditions such as the material and amount of the cloth and the volume of the furnace, and is preferably about 1 to 2 hours, for example. When the time is shorter than 1 hour, carbonization may not be sufficiently performed and desired conductivity may not be obtained. Moreover, when longer than 2 hours, there exists a possibility that embrittlement may advance.

Note that the atmosphere in the furnace in the maintenance step may be an inert atmosphere or a reducing atmosphere. For example, as long as the reducing gas introduced into the furnace in the second temperature raising step exists, the maintenance step may be continuously performed in a reducing atmosphere, or the same as in the second temperature raising step. Further, the maintenance step may be performed while performing a process for making the inside of the furnace a relative reducing atmosphere. As described above, a reducing atmosphere is preferably maintained from the viewpoint of increasing the carbon purity and removing impurities.

“The temperature lowering step” (S0105) is a step of gradually lowering the furnace temperature after the predetermined time has elapsed. A rapid drop in the furnace temperature causes internal stress of the carbonized cloth, which may cause nonuniformity in the structure and properties of the carbonized cloth, and may break or split the fibers constituting the cloth. This step is a step for preventing such an adverse effect. The temperature lowering step is performed in an inert atmosphere or a reducing atmosphere, similarly to the maintenance step, and is preferably performed in the above-described relative reducing atmosphere.

The time spent for the temperature lowering step depends on various conditions such as the material and amount of the cloth and the volume of the furnace, but is preferably 20 hours or more, for example. By slowly decreasing the temperature over this amount of time, it is possible to prevent the above-described adverse effects caused by the rapid temperature decrease.

The “opening step” (S0106) is a step of opening the furnace after the inside of the furnace becomes approximately 100 ° C. or lower by the temperature lowering step. When the furnace is opened in a state where the temperature inside the furnace is high, the carbonized cloth may be in contact with the air and burned.

Note that it is preferable that the opening of the furnace is performed not to maintain the open state after the opening of the furnace for the first time but to open and close the furnace intermittently so that the temperature drop in the furnace is moderate. For example, when opening the furnace for the first time, immediately after opening, the furnace is once closed, and then the furnace is opened again. It is preferable to open and close such a furnace intermittently. Thus, it is preferable to suppress the influence by internal stress etc. by performing a furnace opening so that the furnace temperature may fall gradually.

FIG. 2 is a photograph of the carbonized fabric produced by the carbonized fabric production method of the present embodiment, taken at a magnification of 30 times with an FE-SEM (field emission type scanning electron microscope). The material cloth is a cloth made of natural cotton. FIG. 3 is a photograph of the carbonized cloth taken at a magnification of 100 times. FIG. 4 is a photograph of the carbonized cloth taken at a magnification of 1000 times. 5 to 7 are photographs of the carbonized cloth taken at a magnification of 10,000 times.

FIG. 8 is a diagram showing a result of Raman spectroscopic analysis performed on the carbonized cloth. The spectrophotometer used is “NRS-3100 (JASCO Corporation)” and changed five times (N = 1) under the conditions of laser wavelength of 532 nm, laser light intensity of 10 mW, exposure time of 30 sec, and integration number of 2 times. 1-5) carried out, "G band intensity (1590 cm ^-1)", "D band intensity (1350 cm ^-1)", was determined "Raman intensity ratio (D / G)". According to the measurement results, although the D band intensity is stronger, the G band intensity derived from the graphite structure also exists as it is, so that it is considered that partial graphitization has occurred.

The carbonized fabric manufactured by the manufacturing method of the present embodiment can be applied in various modes as a heating element. FIG. 9 is a conceptual diagram showing carbonized cloth applied as a planar heating element. As shown in the drawing, positive and negative long electrodes are attached to opposing edges of the carbonized cloth (0901) according to the present embodiment (0902, 0903). The carbonized cloth immediately generates heat by connecting the power source (0904) to the positive and negative electrodes and applying a voltage. Such an aspect is suitable when embodied as a floor heating device or a snow melting device.

For example, long and negative electrodes are provided on both side edges in the longitudinal direction of carbonized cloth with a width of 150 mm × length of 1000 mm, and when a voltage is applied by adjusting the voltage to approximately 30 V with a transformer, the current becomes approximately 3 A. Within 2 to 3 seconds after application, the temperature near the surface of the carbonized cloth reaches 80 degrees. Further, this heat generation occurs uniformly throughout the carbonized cloth. Thus, it can be seen that this is an extremely efficient heating element because it reaches a high temperature instantaneously after the power is turned on at an electric power of less than 100 W.

FIG. 10 shows a heating element in which string-like carbonized cloth (1001) is sealed in a quartz glass tube (1002) in a vacuum state. Electrodes are provided at both ends of the string-like carbonized cloth, connected to the power source (1003), and the string-like carbonized cloth generates heat by applying a voltage. Such an aspect is suitable when embodied as a heating device, a cooking device, or a lighting device.
<Effect of embodiment>

The carbonized cloth manufacturing method of the present embodiment can manufacture a carbonized cloth that can be a highly efficient heating element that generates heat instantaneously after power is turned on.

S0101 Fabric placement step S0102 First temperature increase step S0103 Second temperature increase step S0104 Maintenance step S0105 Temperature decrease step S0106 Opening step

Claims

A carbonized cloth manufacturing method for manufacturing a carbonized cloth by heating a cloth containing cellulose in a furnace,
A cloth placement step for placing the cloth in a furnace;
A first temperature raising step for raising the temperature to a temperature before the cloth is carbonized with an inert atmosphere in at least the cloth arrangement region in the furnace;
After the first temperature raising step, the second temperature raising step for raising the temperature to 1200 ° C. to 1400 ° C. by setting at least the cloth arrangement region in the furnace as a reducing atmosphere at least relative to the inert atmosphere in the first temperature raising step. When,
A maintaining step of maintaining the furnace temperature that has reached 1200 ° C. to 1400 ° C. by the second temperature raising step for a predetermined time;
A temperature lowering step for gradually lowering the furnace temperature after the predetermined time has elapsed;
And a furnace opening step of opening the furnace after the inside of the furnace becomes approximately 100 ° C. or lower by the temperature lowering step.
The carbonized cloth manufacturing method according to claim 1, wherein the cloth is made of cotton.
The carbonized cloth manufacturing method according to claim 1 or 2, wherein the predetermined time is approximately 1 to 2 hours.
The carbonized cloth manufacturing method according to any one of claims 1 to 3, wherein a time spent for the temperature lowering step is 20 hours or more.
The method for producing carbonized cloth according to any one of claims 1 to 4, wherein in the furnace opening step, the furnace is opened and closed intermittently so that the temperature in the furnace does not rapidly decrease.