WO2017212299A2

WO2017212299A2 - Artificially produced, intense infrared radiation emitting ceramic composites

Info

Publication number: WO2017212299A2
Application number: PCT/HU2017/000036
Authority: WO
Inventors: Gábor KUNFALVI; Sándor KALMÁR
Original assignee: Kunfalvi Gábor; Kalmár Sándor
Priority date: 2016-06-07
Filing date: 2017-06-02
Publication date: 2017-12-14
Also published as: WO2017212299A3; WO2017212299A8

Abstract

The subject of the invention is the procedure for production of intense infrared radiation emitting composite ceramics, in which: a) we homogenize 31-41 weight% of kaolin, 15-27 weight% of sawdust, 0-1.6 weight% of iron(lll)-oxide, 0-2.60 weight% of titanium-dioxide and 27-46 weight% of lignin at room temperature, whereby we will obtain a paste; b) the paste is extruded into rods, then dried, whereby dry rods will be obtained; c) the dried rods are treated in oxygen-free inert gas atmosphere in two steps: first at 400-650°C. whereby we will obtain baked rods; d) the baked rods are cooled in two stages, whereby we will receive cold rods; e) the cold rods are ground in several stages to average particle size of 2-5 pm, which will give us a composite ceramics powder. Further on, the subject of the invention is the procedure for production of intense infrared radiation emitting composite ceramics, where instead of kaolin tourmaline is used. Also, the subject of the invention is the intense infrared radiation emitting composite ceramics that is produced with our methods, and its application in infrared radiant textile products, infrared emitting hygiene products and in human medicine.

Description

Artificially produced, intense infrared radiation emitting ceramic composites

The invention

The subject of invention is the preparation process of intense infrared radiation emitting composite ceramic material. The method itself lays in homogenization of a certain proportion of natural kaolin or tourmaline with organic components, sawdust and lignin, iron (III) oxide and titanium dioxide, and extrusion of the obtained paste into rods, then drying them, heat treatment of the rods in oxygen-free inert atmosphere, cooling of baked rods and finally grinding of the cold product.

Furthermore, the subject of invention is the ceramic composite with high level of infrared radiation emission, produced by the abovementioned method, and its use in textile products with infrared radiation range, infrared emitting hygiene products and human medicine. Scientific and technical background

All living organisms are subject of electromagnetic radiation reaching the earth from the sun as major source of radiation and from other emitting objects in the interstellar space. With respect to the complete electromagnetic radiation, the infrared radia- tion covers the range of 750nm - 200pm (-14000 - 50cm^"1). It lays between the long wavelengths red edges of the visible and the short edges of microwave spectral regions. Infrared region can be divided into near infrared (NIR, 14000 - 4000cm^"1 or 750nm - 2.5pm), mid-infrared (MIR, 4000 - 400cm^"1 or 2.5 - 25pm) and far-infrared (FIR, 400 - 50cm^"1 or 25 - 200pm) spectral regions.

In essence, each matter absorbs certain proportion of electromagnetic radiation falling on it. Black body is the matter that absorbs all the radiation. When the blackbody is in unchanging temperature state, it emits back this absorbed energy, which is called "blackbody radiation". As the temperature of the body rises, the amount of radiant energy from the material becomes higher. The increase follows the Stefan-Boltzmann law and is proportional to the fourth power of the absolute temperature (T): E= σχΤ⁴ = 5.6697 10^"12 x T⁴ [W/cm²].

One common feature of the infrared radiation is that the effect of radiation weakens in direct proportion to the square of the length. That is, the farther the irradiated body is from the source of the radiation, the weaker the effect of radiation is. Another feature is that the infrared rays do not heat up the main components of air; they only heat up the objects that are irradiated. Some of the infrared radiation is absorbed by the irradiated body, depending on the properties of the body, and is then converted into heat, while the rest is reflected back or passes through the body. In the infrared radiation, the energy is transferred purely in the form of heat, which can be perceived by the thermo receptors in human skin as radiant heat.

Infrared or thermal radiation has been effectively used for thousands of years to treat certain diseases and "repair" discomforts. Heated saunas are only one of the oldest treatments to deliver infrared radiation in controlled environment and controlled "exposure" time. Beneficial effects of naturally occurring Maifan stone, tourmaline and Jade on the human body were recognized by the ancient Chinese as remedy, which were described in various medicinal books. Nowadays, it was found that the beneficial effects of these minerals are the result of 8-14μηι wavelength of infrared radiation emission, causing the molecular level in organisms increase; the molecules get into agitated energy state, which in turn activates biological processes and cell metabolism.

Modern industry has been using infrared emitting materials/items for heating surface of solid objects and drying for several decades. These industrial emitters are usually artificially produced ceramics that have an essential feature of high surface temperature (800-1800°C); their radiation wavelength is between 1.6 - 3.9μιη, while the energy density of the radiating surface is 1.2 - 7.5W/cm².

Some of patents for industrially used infrared radiating materials are related to particular materials/material composites, while others describe the use of these substances in various fields.

Main features of the methods for preparing infrared radiation emitting materials for industrial applications are that they typically contain difficult to access and expensive metal oxides, and the procedures themselves are highly energy consuming (e.g.: need of high heat temperature, above 1000°C), and are also costly for their infrastructure. High temperature conditions in industrial use can also be required for such resulting material composites (for example, these are coatings for baking plates). Therefore, in many cases, these materials can only effectively emit IR radiation in high-temperature condi- tions.

Such procedure example is the KR 100404456 B1 Patent Document, which describes a method of a FIR-emitting ceramic suitable for coating oven surfaces, and thereby makes it suitable for the oven surfaces to use the far-infrared rays, preventing the intermolecular loosening of the ceramics, improving thermal regulation, and prevent- ing the surface of the meat to be baked from sticking. The production involves washing ground natural ceramic material with water, fractionation, agglomeration of water- dispersed ceramic material and its precipitation, multiple heating and rapid cooling of the precipitated ceramics in a rotary kiln, which give us a set of finely divided particles. The ingredients of the ceramics are Si0₂, Al₂0₃, CaO, MgO, Ti0₂, Zr0₂, Na₂0, K₂0, Fe₂0₃, etc. The size of fractioned ceramic material particle is 3-10 micrometres.

Unlike the previous patent, the KR20020009963 Patent describes an antibacterial ceramic glass composite material of high porosity and big surface area, which emits far infrared radiation at room temperature with high efficiency. This material is particularly suitable for using in kitchenware, medical articles and food containers. The used in- gredients are Ag₂0, Li₂C0₃, CaC0₃, Ti0₂ es H₃P0₄. The highest temperature used in the manufacturing process is also very high (1250-1350°C).

The KR 20040096475 A Patent provides a method for preparing high-strength FIR-emitting ceramic balls. This method includes homogenization of 70-90 weight% powder ceramic material and 30-10 weight% of charcoal; forced mixing of the mixture in the presence of water; formulation of ceramic balls by shaping the ceramic mixture into balls with a diameter of 1-25 mm; heating and baking of the ceramic balls in vacuum chamber; rapid cooling of the baked ceramic balls in nitrogen and polishing the surface of the ceramic balls.

The KR 20040104287 A Patent describes process of gaining positive ions and far infrared radiation ceramic materials, which is obtained from mixing clay and ceramic powder containing positive ions. This method includes mixing of 70-95 weight% clay, such as ochre soil, red clay, Jade stone, diamond, gold, etc. with 5-30 weight% of Ca-, K-, Na-, Mg-, Fe-, etc. containing ceramic powder; shaping desired forms; burning them at 600-1000°C, glazing the baked forms, and then baking the glaze at 900-1300°C. The resulting forms are beneficial for the human body and are also environmentally friendly.

The KR 20030017935 Patent also describes production of FIR emitting materials. The process uses amethyst in combination with conventionally FIR emitting materials, which helps achieve an increase in the radiation efficiency. In this process amethyst, jade, ochre soil and ceramic material are used. The sintering is carried out at 850- 1200°C, and after that, glazing is burnt at 1000-2000°C.

The EP 0994827 B1 Patent describes ceramic materials capable of emitting far infrared radiation with better thermic, chemical and physical stability. The aim of this invention is to increase the efficiency of infrared radiation. The goal is achieved with the help of Cr₂0₃ and Fe₂0₃ based material supplemented with CaC0₃. Ceramic material containing Cr₂0₃, Fe₂0₃, Si0₂, MgO, Al₂0₃, CaO and CuO is homogenised with CaC0₃. Then the mixture is melted in a solar furnace at about 2600°C in oxidizing atmosphere, under conditions where oxygen loss is minimized. The melted material is cooled in water and then the obtained material is ground and the powder is applied in the desired objects. The examples show numerical performance evaluation, which is based on the principle that the radiators treated with ceramics will warm up less applying the same electrical power than the radiators coated with the prototype material; and this, is a clear criterion of the fact that the former are capable of greater radiation emission (dissipation). The performance evaluation applies for the temperature range 70-160°C.

In addition to a number of industrial applications, application on human body is also described in the literature.

Thanks to researches and technical developments conducted in the Far East and the USA, there are now infrared radiant elements that can be applied with great intensity without adverse effects in medicine, alternative medicine and cosmetology. Their general characteristics are low surface temperature (60-120°C) and 2-25μιη wavelength infrared radiation.

These infrared rays are invisible and are completely absorbed in the human body. They deeply penetrate below the skin surface where they are converted into thermal energy, and are spread rapidly via the bloodstream throughout the body, causing a pleasant feeling of warmth.

Methods developed for use on the human body are also high energy consuming processes in many cases. This is true despite the fact that the composite materials used on human body need to have high IR emission capacity at low temperatures, thus their thermal stability is not an essential requirement. Nevertheless, they are all produced at high processing temperatures.

For example, Patent KR20050006719 A describes production of ceramic products for medical use capable of far-infrared radiation and anions emission. This process involves mixing of a ceramic powder, aluminium oxide, tourmaline with water, extrusion of the resulting mixture and sintering the cast ceramic mixture at 1400°C. In this way a porous crystalline ceramic material is obtained, which is then mixed with pharmaceutical perfumes and materials with chitosan-component mixture, immersed into edible vegetable oil and finally dried.

The KR 20030080352 Patent also describe a process of manufacturing a ceramic product, which besides IR emission is capable of emission of other components that are beneficial to human health. The KR 20040079798 A Patent discloses a method which has an antibacterial and perfuming effect, as well as far-infrared emitting and ultraviolet-shielding properties. In the process, 65-90 weight% silicon dioxide and aluminium oxide, 1.5-8 weight% magnesium oxide, 1.5-6 weight% calcium oxide, 1.0-10 weight % of sodium oxide, 0.5-7 weight% calcium oxide and small amounts of iron, or 95-99 weight% of aluminium oxide and silicon dioxide are mixed with 5-40 weight% of organic solvent, and the mixture is reacted at lower than 5 Torr pressure at 65-200°C for 1-8 hours.

In Patent KR20010077476 there is also a description of production of a FIR emitting ceramics. In this process silica is processed with conventional ceramic material. The resulting product has sterilizing and deodorizing effects. Main ingredients are silica powder, clay, kaolin, diatomite, and ceramic materials, in addition to calcite, bentonite, dolomite, etc.

Document No US2006/0266979 A1 describes a ceramic powder with high FIR emissivity, high-density bio ceramics produced of it and the whole production process. The process describes stirring of 85-92 weight% alumina, 3-7 weight% of silica, 3-7 weight% of magnesium oxide and 1-4 weight% of clay material with various additives in 60°C water. The particle size of ceramic powder received in the process is 60-80 mesh. During the process, the powder is places into moulds, where it is formed with the help of pressure, and the received ceramic moulds are then sintered for 12 hours in an oxidiz- ing atmosphere at about 1600°C. The obtained bio ceramic material emits beneficial for the human body far infrared rays, reduces and delays formation of harmful oxidation and formation of the polymerization materials when cooking and baking with edible oils and fats. The bio ceramic emission in the range of 5-20μιη is 93% of the emission of a black body at the same temperature.

Document No US 6,591 , 142 B1 describes a material, polyvinyl-fluoride, which is capable of strong IR emission exclusively in the range of 9-12pm and can be shaped well at the same time. In possession of these properties, the material can be used in numerous FIR therapeutic devices.

In the light of the above stated, we can see that there is a great need worldwide for IR radiation emitting materials, such as composites, for human use, which are easily found in nature, readily available inexpensive materials with little additives and can be technologically prepared within low energy consuming technological processes and simple infrastructure. In addition, there is a significant need to ensure intense infrared radiation capable composites, which are better than infrared radiant materials with simi- lar properties found in nature (tourmaline, jade, Maifan stone, Tachi-stone). In addition, these materials have to be effective in emitting infrared radiation at temperatures typical for living conditions (in 20-40°C temperature range).

When the FIR waves penetrate our bodies, they are converted into energy. The production of energy is so close to the radiant energy of the body that our body takes in 93% of the infrared waves reaching the skin. Overdose is not possible because the radiation energy which the cells can no longer utilize will simply pass through them. Radiation activates the self-regulatory system in the tissues to alleviate the upset physical balance and to lead to recovery. As a result of FIR radiation, cells produce enzymes that activate phagocytes, helping them to remove damaged and diseased tissues. The infrared wavelength energy causes raising of temperature and triggers biochemical processes. Another important factor of FIR radiation effect on the human body is that due to the effects of these waves, the nitrogen monoxide, also known as nitric oxide is released, which dilates the capillaries and improves circulation.

The purpose of invention Considering the above mentioned, the purpose of our invention is to provide a ceramic composite material that can be easily found in nature, readily available inexpensive material with little additives and can be technologically prepared within low energy consuming technological processes and simple infrastructure. In addition, it is better than infrared radiant materials with similar properties found in nature (tourmaline, jade, Maifan stone, Tachi-stone) and has better radiant/emitting abilities. Another aim of the invention is that this material manufactured within new technological process has effective emitting infrared radiation capability at temperatures typical for living conditions (in 20-40°C temperature range).

Surprisingly, the ceramic composite obtained within the present invention over- comes not only the tourmaline infrared radiation/emitting ability in the given temperature range, but is also close to the theoretical black body (as theoretical reference) radiation. It approaches 97-99% of the emission levels of laboratory blackbody radiation at a temperature of about 30°C, whereas at the human body temperature (36.5 degrees Celsius), the heat effect is rising. This feature makes it particularly suitable to achieve target- ed biological effects (stimulation of blood and lymphatic circulation, boosting metabolism, stimulation of immune system, increasing oxygen uptake, improvement of hydration ability), as well as efficient use of it in many areas of human medicine (sterilization, pain relief, accelerated regeneration and wound healing, removing toxins from tissue). Developed by us and continually reproducible raw material belongs to the world's most powerful infrared emitting materials. It overcomes by 4-6% not only the emission ^• of rock mineral, tourmaline, which is used for similar purposes, but also by 7-10% some really few artificially produced raw materials with such effects.

Short summary of the invention

The invention provides a method for production of composite ceramic material with intense infrared radiation or emission, where

a) we emulsify at room temperature 31-41 weight% of kaolin with 15-27 weight% of sawdust, 0-1.6 weight% of iron(lll) oxide, 0-2.60 weight% of titanium dioxide and 27 -

46 weight% of lignin, obtaining a paste,

b) the paste is then extruded into rods and dried for several days, thus we receive dry rods,

c) the dried rods are heated to 400-650°C in oxygen-free inert gas in two stages, and finally we obtain baked rods,

d) the baked rods are then cooled in two stages, thus giving us cold rods, e) cold rods are ground in several steps until the particle diameter is 2-5pm, which is how the composite ceramic powder is obtained.

Furthermore, the invention provides a method for an intense infrared radiation- producing composite ceramic in which in the above procedure tourmaline is used instead of kaolin.

In addition, the invention makes intensive infrared radiating ceramic composite possible for using in textile products emitting infrared radiation, hygiene products emitting infrared radiation and in human medicine.

Detailed description of the invention

While working on the invention, particular attention was paid to the use of readily available, inexpensive raw materials and the fact that they can be transformed with low energy consumption and within less costly production steps. These requirements are largely met with application of kaolin, tourmaline, organic material, titanium dioxide, iron oxide, and lignin.

In the process of invention, we used kaolin from Sarisap (Hungary). During the examination with X-ray diffraction phase analysis (XRD) of these crystals, the following components were discovered: kaolinite (Al2Si₂0₅(OH)4 56 weight%, calcite (CaC0₃) 9 weight%, muscovite (KAl2(Si₃AI)O ₀(OH)2) 3 weight%, quartz (Si0₂) 26 weight%, goe- thite (FeOOH) 3 weight%, rutile (Ti0₂) 2 weight%. The content and thermal transformations of kaolinite in the kaolin sample was measured by thermo-gravimetric test. Mass loss of the sample, observed on the basis of derivatograph images, below 1000°C showed the following: between 26°C and 120°C - 1.34 weight% (type: adhering water), between120°C and 650°C - 7.84 weight% (type: kaolinite structural water), between 650°C and 999°C - 3.12 weight% (type: carbonate C0₂ content). In this temperature range, kaolinite was transformed into metakaolinite. Total weight loss of the sample under 999°C was 12.38 weight percentage. Based on the measured weight losses, the kaolin from Sarisap contains 56.4% of kaolinite and 7.1 % of calcite. Chemical content of the kaolinite: 56 weight% Si0₂, 29 weight% Al₂0₃, 10 weight% H₂0, 1 ,3 weight% Fe₂0₃, 0.8 weight% K₂0, 0.6 weight% Ti0₂, 0.6 weight% CaO, as well as little amount of MgO, Na₂0 and organic carbon.

Tourmaline with the best infrared radiation efficiency values used in the invention was from a Chinese sample.

The organic material used in the process connected to the invention is sawdust, which comes from dried hardwood (oak), has high calorific value (15.10 MJ/kg) and low moisture content (8-9%). The moisture content in different experiments was less than 10-12%. Before application of hardwood sawdust, we used a sieve with mash 6.5x6.5 mm. In the present invention, oak can be replaced with other hardwood species as well (pedunculate oak, acacia, beech, hornbeam, etc.), but the softwood species and pines with their burning properties and resin content are factors significantly affecting the result.

The used iron oxide (Fe₂0₃) and titanium dioxide (Ti0₂) are commercially available iron oxide and titanium dioxide.

Lignin used in the invention (30-60% of magnesium lignosulfonate solution (CAS:

8061-54-9) (Magnesium lignosulfonate, liquid (30-60%))) can be found under the trade name of Chemische Werke Zell-Wildshausen GmbH (CWZ), from manufacture in Stockstadt (Germany).

Production of composite ceramic within the invention happens in several steps. The manufacturing steps are as follows: emulsification, extrusion, heat treatment, cooling, drying and grinding.

In the first step, the listed ingredients are homogenized in a kettle equipped with a stainless steel mixer for 40 minutes, at a temperature close to room temperature. It is really important to maintain ambient temperature as described for mixing, because the resulting from mixing frictional heat increases temperature itself. If it overheats, the emulsion becomes too malleable, which could cause problems in the moulding phase. .

The starting weight percentage of the materials in the invention process: 31-41 weight% of kaolin, 15-27 weight% of sawdust, 0-1.6 weight% iron (III) oxide, 0-2.6 weight% of titanium dioxide and 27-46 weight% of lignin.

In a preferred example, the starting weight percentage of the materials in the present invention: 31-36 weight% of kaolin, 15-24 weight% of sawdust, 0-1.4 weight% iron (III) oxide, 0-2.3 weight% of titanium dioxide and 36-44 weight% of lignin.

In a more favourable example, the starting weight percentage of the materials in the present invention: 31-36 weight% of kaolin, 15-24 weight% of sawdust, 1.2-1.4 weight% iron (III) oxide, 1.9-2.3 weight% of titanium dioxide and 36-44 weight% of lignin.

In an alternative example, the starting weight percentage of the materials in the present invention: 36.10 weight% of turmalin, 24.07 weight% of sawdust, 1.44 weight% iron (III) oxide, 2.29 weight% of titanium dioxide and 36.10 weight% of lignin.

In a most favourable example, the starting weight percentage of the materials in the present invention: 31.38 weight% of kaolin, 20.92 weight% of sawdust, 1.26 weight% iron (III) oxide, 1.99 weight% of titanium dioxide and 44.46 weight% of lignin.

After homogenization, the malleable mass is subjected to extrusion in a twin- screw extruder, thus producing 15-20 cm long and 2.5 cm diameter rods. Then, the moulded rods are stored in air-conditioned and well-ventilated room for 12 days, resulting in solid rods with 6-10% weight-loss.

In the next step, the composite ceramic of the invention undergoes heat treatment. When planning heat treatment process, typical atmosphere, temperatures, times, heating profiles as well as all existing knowledge and experience regarding designed materials must be considered. The person who is skilled in this field has the knowledge necessary for choosing optimal heat-treatment. Choosing the optimal heat treatment form is consistent with the goal formulated in the introduction, i.e. to produce a composite ceramic material that shows high infrared emission efficiency at a temperature close to room temperature.

Heat treatment goes on in an inert gas (nitrogen or carbon dioxide) atmosphere free from oxygen.

In one example of the invention, heat treatment was carried out in a furnace heated to 540°C, with subsequent loading of rods, keeping them there for 40 minutes, heating up the furnace to 620°C, further keeping of rods there for 60 minutes, and then taking them.

In a more favourable example of the invention, heat treatment was carried out in a furnace heated to 540°C, with subsequent loading of rods, keeping them there for 5 minutes, heating up the furnace to 620°C, further keeping of rods there for 20 minutes, and then taking them.

But in a most favourable example of the invention, heat treatment was carried out in a furnace heated to 420°C, with subsequent loading of rods, keeping them there for 20 minutes, heating up the furnace to 600°C, further keeping of rods there for 20 minutes, and then taking them.

Heat treatment process must be controlled by a computer, in a furnace with controlled heat treatment process, which should also have an inert-gas transfer system. The inert gas may be nitrogen or carbon dioxide.

The next step in the production is product cooling. This can be achieved in two ways. One option is to place the rods into a bed of sand at room temperature, keeping them away from the ambient air for a few hours, followed by taking them out of the sand. According to another cooling option, ceramic rods, after having been taken out from the furnace, are placed in a closed, insulated "closet", where during cooling, nitrogen or carbon dioxide shielding gas is blown, to ensure airtight environment. After a few hours of cooling phase, the rods can be removed from the cooling area.

The solid ceramic rods should be placed separately for storage in a well- ventilated area at room temperature. The burning and drying loss of the starting materials is about 35-38 weight%. The entire cooling process takes 72 hours.

The last step of the manufacturing process is grinding. First, the rod form of the product should be subject to hammer milling process. The aim of this process is that the product should be brought into shape suitable for a refining procedure. The desired particle size at this stage is 6-8 mm. The second phase is ball milling, which is conducted in a special dry-mill. As a result, the particle size should not be bigger than 1.5-2.0 mm. The main shape and size is obtained in the third process stage. This can be achieved by using an air jet mill. The essence of operation of this device is that material particles hit each other until the desired size is reached, and then the separator will release the particles, which go through the particle sorter. During production, control measurements should be made per amount, which must be carried out with a laser particle analyser and documented. Examining the product efficiency on the basis of infrared emission and other comparatives, our experiments showed that the most effective range is the 2- 5 micron range. This size can be produced with 0.5 kg/hour performance.

The process of micronization provides an opportunity for our material to be used effectively and practically without limitation in almost any application. By using a special milling process with the help of a jet mill, the material is milled into a grain of 2 microns. This means that a cubic centimetre of material forms approximately 5000 square metres of infrared radiating surface. On the one hand, this size provides use of little active agent to achieve a surface with high vibration, and, on the other hand, it makes it possible to apply the material in small size technologies.

We examined the size and IR emission ability of the composite ceramic particles of the invention with the laboratory blackbody radiation for emissivity of different particle composites. We obtained 97.3% of the emission efficiency in the case of average particle size of 2 microns. The radiation efficiency of larger particle size slightly decreased, i.e. we measured 96.6% and 96.0% emissivity respectively for 5 to 10 microns average particle size samples.

For estimation of infrared emission capacity of the ceramic material of the present invention, infrared emission spectroscopy (IRES) is used.

Infrared emission spectroscopy (IRES) is a special branch of experimental infrared (IR) spectroscopy that can be considered as an alternative to the more commonly used ab- sorption, reflection, diffuse reflection or photo acoustic (PA) techniques. The goal of an IR emission measurement is usually the same as that of an IR absorption spectroscopic analysis: to get an insight, through the study of the vibrational energy levels of the system, into the chemical structure, configuration and conformation of molecules, and the characteristics of chemical bonding and intermolecular interactions within the sample.

When producing the IR emission spectrum, the source of IR radiation is the sample itself, which is usually heated at higher temperature than room temperature, and is compared with the black body, having the same temperature as the sample. A practical requirement in IRES is to keep the molecules intact during excitation of emission of IR radiation. Thus, depending on the sample to be examined, the temperature is kept rela- tively low, typically between 40 and 200 °C.

In case of IR absorption, a molecule must go from ground state to an excited vibrational state. IR emission is the opposite process: a molecule must go from an excited vibrational state back to the ground state. However, in order to have a detectable flux of emitted radiation, a significant proportion of molecules must be in the vibrational excited state. This is the principal drawback to IRES: to achieve such a population of vibrational modes, whose transitions are observed in the mid-infrared region, the sample must be heated above ambient temperature. In accordance with Kirchhoff's law, there is a close correspondence between the emission and absorption spectra of a sample.

The laws of thermal radiation concerning the emission of a blackbody play a fun- damental role in optical emission spectroscopy, as they define the conditions for spontaneous thermal emission of any object. An object absorbing all the radiation falling on it is called an absolute blackbody or simply blackbody. On the other hand, emission of black body has maximal emissivity at all wavenumbers of the emission spectrum. The total radiated energy is proportional to the area under the radiance curves. Therefore, the simplest way to measure radiant energy is just by recording single beam emission spectra of black colour composite samples and compare them to the blackbody spectrum measured at the same temperature. Quantitatively it can be done just by integration of the single beam spectra in the whole spectral region exhibiting none zero radiant intensity.

With the applied FTIR spectrometer, we can register one-beam emission spectra, which provide emitted radiation energy distribution of the wave-scale (measuring unit cm^"1). The energy distribution can be found in the ordinate scale. The spectrometer software gives and displays this energy value in so-called "arbitrary units". The intensity distribution of blackbody radiation is known from the Planck law of emission. Thus, the measured emission spectra of one beam ordinate can be precisely stated either in W/cm³, or in J m^"1 -s^"1 units. In the literature, the emission-ordinate scale has several names: Spectral radiance, Spectral radiant energy density or Energy density (arbitrary units). For our measurements, we used the last, more comfortable scale, which is automatically applied by the spectrometer.

Nevertheless, the emission energy range can be specified in units of absolute energy density, on the basis that the maximum intensity of black body emission at temperature 323K (50°C) is 5 10^"3 W/cm³. So the "maximum intensity of radiation" (MIR) can be converted into energy density (W cm³) units, instead of "arbitrary units".

Emission properties of a sample can be quantitatively stated in such a way, that the integral intensity of the emission spectrum (area under the curve) is compared to the black body radiation integral intensity. These values are called "integrated emission intensity" (I El), and integration is carried out in the entire measurement range (4000-200 cm^"1). Integration is automatically performed by the spectrometer software on colour images in a digital format. On our images, the emitted energy is always shown in arbitrary units. For the quantitative evaluation of performance of the ceramics of our invention, we have used the integrated emission intensity (IEI) values, on one hand; and radiation intensity maxima (RIM) on the other hand. IEI values of ceramics of our invention out- perform the measured/calculated IEI values of tourmaline at similar temperature.

Sample preparation for IR emission measurements of black powders is very difficult (as it is in the case of the composite ceramic of the invention), since it is difficult to control the thickness and quantity of the sample in powdered form. The first step in transformation of the disadvantaged sample was carried out in a mill, by homogenizing the ceramics with potassium bromide (KBr) powder, as non-emitting material. Then the homogeneous fine powder was pressed into a 13 mm diameter pellets. Obtained in this way ceramic powder embedded into KBr matrix, is perfect for determination of emissivi- ty of the ceramics of our invention.

Further performance evaluation of the composite ceramics of the present inven- tion can be done visually. The visual assets are partly the IR emission spectra themselves; on the other hand, they are represented on infrared thermal images of humans. The infrared images were measured with Somatoinfra®.

The IR emission spectra curves showed that the IR-emission performed by the ceramics approximated the theoretical black body radiation. The emitted energy, from the point of its effect on the human body, is very significant in relevant wave-number range, i.e. approaches the theoretical black body radiation, or radiation emitted by the black body used in laboratories. The IR emission spectra curves also show that the high IR emission ability of the exposed ceramic can be most effectively used at room temperature (25-35°C). This makes ceramics particularly suitable to achieve targeted bio- logical effects, as well as to use effectively it in human medicine.

What concerns theoretical background of Somatoinfra® measurements, one should know that the infrared camera used for diagnostic testing receives signals radiated by the human body in infrared range, and transmits them to a specific computer. The computer converts the signals into range that can be detected by the human eye, which allows you to see these rays. The infrared diagnostic test is therefore not temperature measuring test, not a simple heat map. It can depict the dynamic life processes (or infrared radiation emitted by them) with high sensitivity and precision. Thus, it can visualize different inflammations, tumours, varicose disorders, degenerative changes of spine and joints, as well as other cellular metabolic processes. Description of Figures

Figure No.1 : Derivatogram of non-heat-treated material

Figure No_:2: Derivatogram of heat-treated product

Figure No.3: Microstructure of the ceramic composite material (3000-x magnification) Figure No.4: SEM image of the ceramic composite particles crystalline (20000-x magnification)

Figure No.5: Microstructure of the carbon inclusions in the ceramic composite

Figure No. 6: SEM diffraction pattern of the carbon inclusions in the ceramic composite Figure No.7: Comparing the theoretical black body radiation with the composite sample emissions, produced in the synthesis described in Example No.7, at 25°C (lowest), 50°C (middle) and 70°C (top) temperatures. The emission patterns have been corrected with the emissions of the device.

Figure No.8: The emission spectrum of composite ceramics of Example No.7 at 50°C

(top) and infrared absorption spectrum of the sample (bottom)

Figure No.9: Thermal image recorded before wearing the neckband

Figure No.10: Thermal image recorded after wearing the neckband

Examples

Example No.1

600 g of kaolin were put into a kettle supplied with a stainless steel mixer, which was then mixed at 15-28°C temperature for 3 minutes with the speed of 25-30 rev/min; and then 400 grams of sawdust were continuously added for 1 minute and the obtained mixture was stirred for 5 minutes. While mixing continuously, with 1 minute of feeding time, 240 g of iron (III) oxide and 380 g of titanium dioxide were added, and the obtained mixture was stirred for another 5 minutes. In the next phase, the measured (600 g) lignin was added. The duration of continuous mixing was another 5 minutes. The material was then stirred for another 20 minutes in a continuously operating emulsifier. The total combining and mixing time lasted approximately 40 minutes.

The mixture obtained after homogenisation was then shaped in the extruder.

With the help of the twin-screw extruder, 15-20 cm long, 2.5 cm in diameter rods were formed, which were then placed separately on ventilating material, well separating them from the other rods, providing the perfect air circulation. The ventilating device must be a flat horizontal surface. The moulded products must be kept in air-conditioned, well- ventilated area. The constant temperature should be within range of 17-19°C during this time. The bars have to be rotated every 3 days by 90 degrees, until about 6.0-7.0 weight% loss is achieved. This period took 12 days. After the rods had been fully dried, they were be kept in a well-ventilated dry place until baking.

Heat treatment of the rods was carried out in a computer-controlled DENKAL 6B type heat treatment furnace, which has an inert-gas transfer system and a temperature control unit. Heat treatment was carried out in an oxygen-free environment in nitrogen (or C0₂) atmosphere, and that started with heating up the furnace to the temperature of 420°C. The furnace interior, from the moment of its opening to the time of inserting the rods, cools back to about 390-400°C. Keeping the rods at constant temperature (420°C) took about 20 minutes. After that, the furnace was heated up to 600°C and the rods were kept in the furnace for additional 20 minutes.

The next step of the process was removing the rods from the furnace. This consisted of placing the rods onto the prepared 20°C cold sand bed, taking into consideration that hiding the rods and thereby closing them off from the ambient atmosphere must be achieved very fast (preferably within 10 seconds). The process of cooling was carried out for 3 hours, after which the rods were removed from the cooling matter. The hardened rods should be stored separately from each other, in well-ventilated area, at 20-22°C. The active ingredient loss during baking and drying is about 35-38%. Total cooling time was 72 hours.

The final step of the procedure is the grinding process. First, the rods should be subject to hammer milling process, after which the obtained desired particle size is 6-8 mm. The next phase is ball milling, which is conducted in a special dry-mill. As a result, the particle size should not be bigger than 1.5-2.0 mm. The last step of grinding (mi- cronization) was carried out using an air jet mill.

During micronization, control measurements should be made per amount with a laser particle analyser. Examining the product efficiency on the basis of infrared emission and other comparatives, our experiments showed that the most effective range is the 2-5 micron range. This size can be produced on used devices with 0.5 kg/hour performance.

According to the spectrometer detector's smallest amplification degree ("A"), the integrated emission intensity of the composite ceramic material obtained in this way at 50°C was 69.51 , while the maximum intensity was 0.0695. For tourmaline, these values were 64.01 and 0.0647, or in the case of the black body, the values were 82.5 and 0.0908 respectively. The integrated emission intensity of composite ceramic is greater than that of the tourmaline, and approximates -the integrated emission intensity measured for the black body at a similar temperature.

Example No. 2

Composite ceramics of this example was prepared in the same way as in Example No.1 , except that instead of kaolin, tourmaline was used. The amount of the mixed ingredients in the kettle was as follows: 600 g tourmaline, 400 g of sawdust, 240 g of iron oxide, 380 g of titanium dioxide, 600 g of lignin.

Integrated emission intensity of the ceramic composite obtained in this way at 50°C was 70.23, while the maximum of the radiation intensity was 0.0699 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is greater than that of tourmaline, and approximates the integrated emission intensity of the black body measured at a similar temperature. Example No.3

Composite ceramics of this example was prepared in the same way as in Example No.1. However, the amount of the mixed ingredients was as follows: 700 g of kaolin, 300 g of sawdust, 240 g of iron oxide, 380 g of titanium dioxide, 900 g of lignin.

Integrated emission intensity of the ceramic composite obtained in this way at 50°C was 71.36, while the maximum of the radiation intensity was 0.0706 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is greater than that of tourmaline, and approximates the integrated emission intensity of the black body measured at a similar temperature. Example No.4

Composite ceramics of this example was prepared in the same way as in Example No.1 , except that we did not use iron oxide or titanium dioxide. The amount of the mixed ingredients was as follows: 600 g of kaolin, 400 g of sawdust, 800 g of lignin.

Integrated emission intensity of the ceramic composite obtained in this way at 50°C was 71.1 , while the maximum of the radiation intensity was 0.0702 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is greater than that of tourmaline, and approximates the integrated emission intensity of the black body measured at a similar temperature. Example No.5

Composite ceramics of this example was prepared in the same way as in Example No.1. However, the amount of the mixed ingredients was as follows: 600 g of kaolin, 400 g of sawdust, 240 g of iron oxide, 380 g of titanium dioxide, 650 g of lignin.

Integrated emission intensity of the ceramic composite obtained in this way at

50°C was 70.08, while the maximum of the radiation intensity was 0.0709 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is greater than that of tourmaline, and approximates the integrated emission intensity of the black body measured at a similar temperature.

Example No.6

Composite ceramics of this example was prepared in the same way as in Example No.1. However, the amount of the mixed ingredients was as follows: 600 g of kaolin, 400 g of sawdust, 240 g of iron oxide, 380 g of titanium dioxide, 800 g of lignin.

Integrated emission intensity of the ceramic composite obtained in this way at

50°C was 75.27, while the maximum of the radiation intensity was 0.0762 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is greater than that of tourmaline, and approximates the integrated emission intensity of the black body measured at a similar temperature.

Example No.7

Composite ceramics of this example was prepared in the same way as in Example No.1. The amount of the mixed ingredients was as follows: 600 g of kaolin, 400 g of sawdust, 240 g of iron oxide, 380 g of titanium dioxide, 850 g of lignin.

Integrated emission intensity of the ceramic composite obtained in this way at

50°C was 80.84, while the maximum of the radiation intensity was 0.0810 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is much greater than that of tourmaline, and approximates the integrated emission intensity of the black body measured at a similar temperature.

Example No.8

Composite ceramics of this example was prepared in the same way as in Example No.1. The amount of the mixed ingredients was as follows: 600 g of kaolin, 400 g of sawdust, 240 g of iron oxide, 380 g of titanium dioxide, 400 g of lignin. Integrated emission intensity of the ceramic composite obtained in this way at 50°C was 68.59, while the maximum of the radiation intensity was 0.0679 (in case of detector amplification degree "A"). Integrated emission intensity of the composite ceramic is greater than that of tourmaline, and approximates the integrated emission in- tensity of the black body measured at a similar temperature.

To sum up, in Table No.1 we can see that the quality and quantity of used initial materials influence the integrated emission intensity (lEl) and the maximum radiation intensity (SIM) values.

Table No.1

Note: ^* The intensities are given in relative intensity values, which were measured with detector amplification degree "A". Example No.9: Selection of heat treatment temperature profile

The essence of the heat transfer experiments within protective gas atmosphere is to find the optimal heat treatment form after finally decided composition of the product, which leads to the highest efficiency infrared emission and can be continuously reproduced.

Composite ceramics of Example No.7 was subjected to the following heat transfer profiles:

A) Heating up to 540°C, loading, keeping at temperature for 45 minutes, removing;

B) Heating up to 540°C, loading, keeping at temperature for 40 minutes, heating up to 620°C (in 10 minutes), keeping at temperature for 60 minutes, removing;

C) Heating up to 540°C, loading, keeping at temperature for 45 minutes (without protective gas), removing; D) Heating up to 420°C, loading, keeping at temperature for 20 minutes, heating up to 600°C (in 20 minutes), keeping at temperature for 20 minutes, removing;

E) Heating up to 550°C, loading, keeping at temperature for 50 minutes, removing;

F) Heating up to 620°C, loading, keeping at temperature for 45 minutes, heating up to 680°C (in 20 minutes), removing;

G) Heating up to 680°C, loading, keeping at temperature for 65 minutes, removing;

H) Heating up to 540°C, loading, keeping at temperature for 35 minutes, heating up to 680°C (in 10 minutes), removing;

I) Heating up to 540°C, loading, keeping at temperature for 15 minutes, heating up to 620°C (in 0 minutes), keeping at temperature for 20 minutes, removing;

J) Heating up to 540°C, loading, keeping at temperature for 20 minutes, heating up to 620°C (in 10 minutes), keeping at temperature for 70 minutes, removing;

K) Heating up to 1080°C, loading, keeping at temperature for 40 minutes, removing;

L) Heating up to 350°C, loading, keeping at temperature for 20 minutes, heating up to 540°C (in 35 minutes), keeping at temperature for 20 minutes, removing;

M) Heating up to 540°C, loading, continuous heating up to 1080°C, removing and cooling.

Table No.2 contains integrated emission intensity (IEI) and the maximum radiation intensity (SIM) values of the A-M heat treatment profiles of the composite ceramics.

Table No.2

Note: * Values were measured with detector amplification degree "A". After analysing the different heating profiles, we can make the following statements:

1) On the basis of heat treatment, it can be stated, that using protective gas is essential, as in profile C it is almost impossible to evaluate the emission values;

2) Low temperature (540°C) is not enough for reaching desired infrared emission intensity (profiles A and L);

3) Extremely high temperature (1080°C) is too high (kaolin breaks down), thus the infrared emission intensity of the samples is worsening (K and M profiles);

4) Worsening emission values were detected in too long combustion processes and in "one-step" heat treatments (E, G, J profiles);

5) Ideal infrared emission values were observed for the samples prepared in the range of 540-620°C, especially the values where after continuous heat treatment we followed with heating up, then heat-treated the samples at the higher temperature as well (B, D, H, I profiles).

The most intense infrared emission value were shown by D profile.

Example No.10: Analytical studies of phase composition and microstructure of composite ceramics A. STUDY OF NON-HEAT-TREATED RAW MATERIAL

Thermal behaviour of the non-heat-treated raw material mixture of Example No.7 was tested with the help of a derivatograph. On the basis of derivatograph measurements, we determined the following weight losses of the raw materials: between 26°C and 207°C - 15.1 weight% (adhering water evaporates), between 209°C and 400°C - 20.8 weight% (organic acids of sawdust and some of the Iignin decompose), between 400°C and 990°C - 25.9 weight% (structural water of kaolinite evaporates, charcoal and Iignin contents burn out and carbonate decomposition takes place). Total amount of mass loss is 62.49%. We also measured weight loss after 2 hours at 1 10°C in drying cabinet. Mass lost after drying was 13.34%. These results also show substantial absorbent capacity of the material; the first peak on the derivatograph image (Figure No.1 ) comes from adherent water evaporation.

Starting raw material sample used in Example No. 7 was also subjected to ther- mo-gravimetric analysis, up until the final temperature of 1000°C (Figure No.2). In the first step, the adsorbed water (surface water) leaves the composite and mass loss is 4.81 %. Different OH groups of kaolinite decompose fully at 370°C; weight loss% is 9.05. The last step in weight loss is between 370-830°C, which involves decomposition of kaolinite into metakaolinite, as well as burnout of finely dispersed carbon inclusions. The total weight loss is 44.05%

B. STUDY OF HEAT-TREATED UNGROUND PRODUCT

In this study, the crystalline component composition of the composite ceramics of Example No.7 was determined with X-ray diffraction study (XRD), and the chemical composition with X-ray spectrometry (XRFS).

As a result of X-ray diffraction (XRD) study, the following crystal components were found: kaolinite (AI₂Si₂0₅(OH)₄) 16 weight%, calcite (CaC0₃) 6 weight%, musco- vite (KAl2(Si₃AI)O₁₀(OH)₂) 1 weight%, quartz (Si0₂) 18 weight%, magnetite (Fe₃0₄) 3 weight%, Rutile (Ti0₂) 2 weight%. The missing quantities are the so-called X-ray amor- phous materials, which after kaolinite decomposition are metakaolinite, amorphous carbon, charred wood, and lignin. Great proportion of the composite (54 weight%) showed amorphous properties. These components can be fine carbon inclusions, amorphous metakaolinite or organic residues from the lignin. It is impossible even to estimate the mass of the X-ray-amorphous, non-crystalline phase. Given quantitative data is for in- formation purposes only. Based on the identified stages, what concerns heat treatment, we received confirmation that the temperature of heat treatment (permanently) did not reach 600°C (kaolinite was present), and that heat treatment was accomplished in a reducing atmosphere (conditions of oxygen deficiency) (magnetite was generated from goethite).

Results of X-ray powder diffraction test analyses of the kaolinite clay mineral and the composite of Example No.7 are shown in Table No.3

Table No.3

Kaolinite clay Compo¬

Phase analysis Quantity site Notes

Name Stoichiometry (weight%) (weight%)

Kaolinite AI203(OH)4 56 16

Quartz Si02 26 18

Calcite CaC03 9 6

Muscovite KAI2(Si3AI)O10(OH)2 3 1

Goethite FeOOH 3 - Transfor¬

Rutile Ti02 2 2 mation

Magnetite Fe203 - 3 New phase

XRD amorcoal, metakaolinite, etc. 45 54

phous Chemical composition specified with the X-ray spectrometry (XRF) (at 00°C) is the following: Na₂0 1.76%, MgO 3.66%, Al₂0₃ 14.60%, Si0₂ 21.00%, K₂0 0.80%, CaO 1.26%, Ti0₂ 6.80%, Fe₂0₃ 3.61 %, S 1.30%, CI 0.028%, MnO 0.80%, C loss on ignition 40,0%.

Trace element content (ppm) is the following: Co 9.9, Ni 7.5, Cr 4.4, Cu 14.1 , Pb 120.3, Zn 43.8, Rb 183.1 , Sr 80.1 , Y 33.4, Zr 82.2, Mo 5.3, V 21.4, Nb 20.2, Cs 16.0, Ba 808.2, La 71.5, Ce 84.4, Pr 19.8, Nd 67, Th 17.2.

In the X-ray fluorescence analysis, about 56 weight% of the main components are various oxides, whereas calcination loss is about 44 weight%. Surprisingly, many trace elements were found, which may come from naturally occurring kaolinite.

C. STUDY OF THE FINISHED PRODUCT, GROUND UNDER 2pm GRAIN SIZE

As a result of X-ray diffraction (XRD) study, the following crystal components were found: kaolinite (AI₂Si₂0₅(OH)₄) 16 weight%, calcite (CaC0₃) 6 weight%, muscovite (KAI₂(Si₃AI)Oio(OH)₂) 1 weight%, quartz (Si0₂) 22 weight%, magnetite (Fe₃0₄) 8 weight%, Rutile (Ti0₂) 2 weight%, CaMg(C0₃)₂ traces. The missing quantities are the so-called X-ray amorphous materials. Example No.11 : SEM examination of the composite ceramics

This example demonstrates the image of composite ceramics of Example No.7 made with scanning electron microscope (SEM Scanning Electron Microscopy) (Figure No.3).

It can be seen that particle size changes between 2.2 pm and 6.2 μιη, and that the average particle diameter is about 4.2 pm. An individual crystalline particle SEM image is shown in Figure No.4.

The large solid particle (the size of which is about 4x8 pm) consists of different fragments of 200 nm size; the dark spots shown in the picture are the integrated finely divided carbon particles. The carbon inclusions are shown in Figure No.5.

The large carbon agglomerate comprises smaller fragments from 50 to 80 nm in diameter, which form an agglomerate bundle of about 1.4x0.6 pm (the circle diameter is about 1 pm). The fine structure of the bundles suggests that carbon inclusions have high specific surface area. It is interesting to note that carbon inclusions show a weak diffraction pattern (Figure No.6), suggesting that part of carbon inclusions has crystalline graphite structure. Example No.12: IR emission measurements of the composite

Evaluation of IR emission properties of the composite ceramics of Example No.7 was made using IR emission spectra of different temperatures. The first step was to mix the ceramic powder with potassium bromide powder, which does not emit IR radiation. The amount of the ceramic powder, based on total weight of the ceramic powder and potassium bromide was 5.250±0.005 weight% (i.e. 94.75 mg KBr powder was mixed with 5.250 mg ceramic powder). The powder mixture was homogenized in a vibratory mill. The homogeneous fine powder was compressed into tablets with 13 mm diameter. For heating the tablets, we used a HAAKE Phoenix water thermostat; heating was carried out with hot water circulation. Temperature stability was about ±0.1 °C. For creating a MIR (4000-200 cm^"1) emission spectrum image of the heated tablets, we used a FTIR spectrometer of Bomem MB- 02 Michaelson type. The spectrometer was equipped with a caesium iodide-based Ge-Beam splitter, and a DTGS (deuteron-triglycine-sulphate) detector at room temperature. We blew dry nitrogen through the spectrometer. The spectral range of the spectrometer was 4000-200 cm^"1, the selected spectral resolution was 4 cm^"1, and we accumulated 36 interferograms in the emission experiments. We used a Bio-Rad FTS 40 spectrometer for FIR range (700-50 cm^"1) analyses, which was equipped with a wire mesh light divider and a polyethylene windowed DTGS detector. Rinsing of the FIR spectrometer was ensured with efficient air dryer. The spectral range of the spectrometer was 700-50 cm^"1; the selected spectral resolution was 4 cm^"1. For measurements, we accumulated and averaged 256 images.

Emission spectra of the composite ceramics measured at the temperatures of 25, 50 and 70°C can be seen in Figure No.7. For reference, we also depicted the emission spectra of the theoretical black body at the same temperatures. As shown in the figure, the composite ceramics is capable of higher IR emission performance in the range of 980-2000 cm ¹, at 50°C and 70°C than the theoretical black body: the energy emitted in this wave number range is slightly higher than the energy emitted by the theoretical black body. This is not a violation of a general law of physics; we will explain it further on.

The figure shows that the difference in emission between the ceramics and the theoretical black body is in range between 3000 cnr¹ and 680 cm ¹, and at 50°C is the biggest, i.e. 28%, while at 70°C, it is only 14%, and at 25°C - just 4%. The observed difference decreases with rising of temperature, at 70°C and in range over 1500 cm^"1, the energy emitted by the black body and the ceramic shows high degree of matching. However, at 100°C in the above spectral range, deviation, from the theoretical black body radiation cannot be detected, that is, the sample acts like a black body. Unfortunately, emission spectra measured at 25°C is close to the spectrometer's so-called 'own emission' and is difficult to interpret. Another footnote is that in the range less than 700 cm^"1, light transmittance of the spectrometer decreases rapidly, and at 200 cm^"1, reaches the baseline value (i.e., zero energy). That is why measured emissions are not comparable to the theoretical values in the range under 700 cm^"1.

Figure No.8 shows the explanation of the so-called extra emission appearance. Typical silicate emission bands in the range of 1180-850 cm^"1, characteristic to the ceramic composite, can be well recognized in the upper single beam emission spectrum. Similarly, we can slightly see the 590 cm^"1 and 1416 cm-¹ bands of carbonate. These weak and broad bands are superimposed onto the composite sample blackbody radiation, increasing its intensity. The effect can most likely be explained as rare phenome- non of infrared luminescence. It can be agitated by infrared radiation, by lower layers of black body radiation of the sample or simply by heating. In our experience, the IR luminescence is the most intense in the temperature range between 30°C and 50°C.

The experiment demonstrates that intense IR emission of ceramics exposed to heat effect can be most exploited at temperatures below 50°C. This property makes ce- ramies particularly suitable to achieve intended biological effects and to use it efficiently in human medicine.

Example No.13: Somatoinfra® measurements

For the performance evaluation of IR emission of ceramic composite of Example No.7 we made Somatoinfra® measurements. The measurements were made using fabrics containing ceramic powder and putting it on different parts of the human body. Ceramic powder can be applied on fabric in two ways. One of them is to apply the ceramic powder on the finished fabric; another is to apply ceramic powder on cotton or polyam- ide textile fibres.

In the first case, the ceramic powder has to be emulsified with the carrier material in proportion of 2-5 weight%. Depending on the type of textile, this carrier can be a der- matologically tested skin friendly silicone or polyurethane. The agent can be screen printed on the selected fabric surface with the help of a uniquely patterned template. Fixing can be done by heat treatment or UV-stabilization. In the second case, two options are available. In case of polyamide fibres, an emulsion has to be applied for weaving the infrared active substance into the fibre, and the ceramic powder ration should not be greater than 3.5 weight% of polyamide. Due to the low d-tex size of polyamide fibre, the size of micronized ceramics may not be great- er than 1.5 pm, since it would lead to immediate breaking, damage or loss of flexibility of the fibre.

In case of natural cotton fibre, we use special textile dyes. First, the textile dye has to be mixed with the active agent, whereby we receive a physically and chemically stable slurry structure. Preferably, we use various emulsifiers and stabilizers applied in textile industry, which provide compatibility between the active agent and the textile dye. Then, standard procedure of dying in textile industry takes place. The amount of the active agent in the dye is maximum of 3-4 weight%, whereas the particle diameter is 2.5- 3.5 pm.

During experiments, we examined the effects of the textiles, made as described above, on different parts of the body. First, we measured heat energy radiation of the surveyed person's body part to be examined. Figure No. 9 depicts the heat image before wearing the fabric. Figure No.10 shows heat radiation of the affected part of the body after wearing the fabric for 30 minutes as a neckband.

In addition to thermal image, the amount of absorbed heat energy can also be determined. Converting heat energy into degrees Celsius, we can calculate the degree of detected temperature change on the body surface treated with ceramic powder. Changing the absorbed heat energy into degree Celsius, we observed increase of treated body surface temperature in range between 0.173°C and 0.225°C.

Claims

Patent claims

1. Procedure for intense infrared radiation ceramic composite preparation, char- acterized by the following:

a) we homogenize 31-41 weight% of kaolin, 15-27 weight% of sawdust, 0-1.6 weight% of iron(lll)-oxide, 0-2.60 weight% of titanium-dioxide and 27-46 weight% of lignin at room temperature, whereby we will obtain malleable but mouldable paste,

b) the paste is extruded into rods, then dried for several days, whereby a dry product will be obtained,

c) the dried rods are treated in oxygen-free inert gas atmosphere in two steps: first at 400-550°C for 15-40 minutes, then after repeated heating to 620°C, for another 30-70 minutes, whereby we will obtain baked rods,

d) the baked rods are cooled in two stages: first, for several hours to reach room tem- perature, then for few days more, to receive cold rods,

e) the cold rods are ground in several stages to average particle size of 2-5 μιη, which will give us a composite ceramics powder,

where the sum of weight percentage of the input materials is always 100 weight%.

2. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: we homogenize the input materials listed in step a), i.e.31-36 weight% of kaolin, 15-24 weight% of sawdust, 0-1.4 weight% of iron(lll)-oxide, 0-2.3 weight% of titanium-dioxide and 36-44 weight% of lignin, where the sum of weight percentage of the input materials is always 100 weight%.

3. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: we homogenize the input materials listed in step a), i.e. 31-36 weight% of kaolin, 15-24 weight% of sawdust, 1.2-1.4 weight% of iron(lll)-oxide, 1.9-2.3 weight% of titanium-dioxide and 36-44 weight% of lignin, where the sum of weight percentage of the input materials is always 100 weight%.

4. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: we homogenize the input materials listed in step a), i.e. 31.38 weight% of kaolin, 20.92 weight% of sawdust, 1.26 weight% of iron(lll)-oxide, 1.99 weight% of titanium-dioxide and 44.46 weight% of lignin.

5. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: we homogenize the input materials listed in step a), i.e. 36.10 weight% of turmalin, 24.07 weight% of sawdust, 1.44 weight% of iron(lll)-oxide, 2.29 weight% of titanium-dioxide and 36.10 weight% of lignin.

6. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: as described in step c), the dried rods are treated in oxygen-free inert gas atmosphere in two steps: first at 540°C for 40 minutes, then after repeated heating to 620°C, for another 70 minutes, to obtain baked rods defined in step c).

7. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: as described in step c), the dried rods are treated in oxygen-free inert gas atmosphere in two steps: first at 540°C for 15 minutes, then after repeated heating to 620°C, for another 30 minutes, to obtain baked rods defined in step c).

8. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: as described in step c), the dried rods are treated in oxygen-free inert gas atmosphere in two steps: first at 420°C for 20 minutes, then after repeated heating to 600°C, for another 40 minutes, to obtain baked rods defined in step c).

9. The procedure for production of intense infrared emitting composite ceramics described in claim point No. 1 , characterized by the following: the cold rods, defined in step e) are micronized in several stages: first, to 6-8 mm, second, to 1.5-2.0 mm, then finally, to average particle size of 2-5 μπι, which will give us a composite ceramics pow- der determined in step e).

10. Intense infrared emission radiating composite ceramics, produced in procedure defined in claim point No. 1.

11. Intense infrared emission radiating composite ceramics, produced in procedure defined in claim point No. 8.

12. Application of composite ceramics defined in claim point No.10 or No.1 1 , in infrared radiant textile products, infrared emitting hygiene products and in human medicine.

The authorized person: