JPS61252364A - Composite fiber and fiber structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to fibers with good heat absorption and low emissivity. More specifically, the present invention relates to heat ray absorption and heat ray selective absorption fibers that have a high ability to absorb high-temperature radiant heat and emit less self-heat.

[Prior art]

The technical content of fiber insulation materials that have been proposed to date has mostly been to incorporate a large amount of air with low thermal conductivity, and to further prevent air convection, the air layer has been subdivided into fibers.

Recently, in order to prevent heat radiation, which is another factor in heat transfer, the use of mirror surfaces has been considered and has already been put into practice.

[Problem that the invention seeks to solve]

However, the method of simply combining mirror surfaces and fibers to prevent heat radiation, for example, when used as clothing, can prevent the radiation of human body heat, but it also reflects and blocks the heat rays of high-temperature bodies from the outside. This will cause inconvenience.

[Purpose of the invention]

The present invention solves these problems and provides a fiber that is absorbent and heat-retaining, that is, can absorb heat rays from the outside and raise the internal temperature, while at the same time blocking the transfer of heat such as human body temperature.

[Means for solving problems]

In order to solve this problem, the present invention employs the following configuration. In other words, a heat ray absorbing material that exhibits absorbency for electromagnetic waves with an average wavelength of 7 μm or less and an average wavelength of 1
It is a composite fiber in which at least one substance selected from heat ray reflective substances that exhibits reflectivity for electromagnetic waves of 4 μm or more is present on at least a part of the surface of the fiber main body, and one is a composite fiber with this composite fiber and another substance. It is a fibrous structure made by mixing fibers.

The heat ray absorbing substance in the present invention has the ability to selectively absorb electromagnetic waves with an average wavelength of 7 μm or less, and can be applied or sprayed to a desired thickness on part or all of the surface of the fiber body. It can be coated or laminated by appropriate means such as lamination or lamination. An example of such a substance is chromium.

Metal compounds that can be deposited or plated, such as cobalt, copper, aluminum, etc., with metal oxides showing particularly favorable performance. In the present invention, those having an absorption capacity of 80% or more are preferably selected. The thinner the metal oxide film is, the more selectively absorbing electromagnetic waves it exhibits, and a unique performance emerges in that it absorbs heat rays with an average wavelength of 7 μm or less, but reflects heat rays with an average wavelength of 14 μm or more. .

The heat ray reflective material in the present invention is defined as having an average wavelength of 14
It is a material that has the ability to reflect electromagnetic waves of μm or more, and can be laminated to an arbitrary thickness on the fiber surface using the same method and form as the heat ray absorbing material. Examples of such substances include the metals mentioned above, and it is important that the metals form a mirror surface state.

For example, it is effective to use materials that have a mirror effect, such as aluminum powder adhered to the fiber surface together with a binder, or vacuum-deposited aluminum.

There is no limit to the laminated thickness of these metals and metal compounds, but for applications requiring flexibility and texture, thinner layers are preferable, and the layer thickness is 1000 μm or less, preferably 500 μm or less.

The energy radiated by an object increases as its surface becomes hotter. The electromagnetic wavelengths emitted at this time are distributed, with higher temperatures shifting toward shorter wavelengths. The average electromagnetic wavelength can be obtained from the Wien displacement law using the following formula, assuming that the radiating object is a black body.

5326/T=λ T: Absolute temperature (Ko) λ: Average photon wavelength (μm) In the present invention, it is necessary for the short wavelength absorption portion to absorb a large amount of electromagnetic waves emitted from a body with a temperature higher than about 760 K. be.

Such fibers absorb electromagnetic waves from high-temperature solids and transmit heat inside through the composite fibers by conduction and convection, providing warmth to the inside of the fiber structure, such as the human body, but in general, they absorb heat rays. Objects with good heat rays emit large amounts of heat, resulting in large losses. When a heat radiating object is a black body, it radiates thermal energy proportional to the fourth power of the absolute temperature, as defined by the Stefan-Boltzmann law, but heat radiation can be prevented by using a mirror surface for the radiating object. The heat rays emitted from the human body are distributed in the long wavelength region. The average wavelength is about 14 μm according to Wien's displacement law, and when used as heat-absorbing thermal clothing, a surface that reflects this wavelength range is required. The composite fiber of the present invention may also be used as a fiber product that emits wavelengths of about 14 μm, and those that reflect wavelengths longer than this wavelength are effective.

The lower the thermal emissivity, the greater the effect, but a binder is sometimes used to provide durability, and in this case the thermal emissivity tends to be high, but the thermal emissivity is 20%.
The following are valid. In the present invention, the above-described heat ray absorbing substance may be attached to any fiber, or the heat ray-low emissivity substance may be attached to any fiber. Furthermore, in the present invention, these two types of composite fibers may be used as a mixture, or one of these composite fibers may be mixed with another fiber, or the above two types of fibers may be mixed with another fiber. It can also be used in combination with fibers.

In the present invention, the two types of substances mentioned above may be bonded to the surface of the fiber body as long as they are attached to at least a portion of the fiber body, and may be attached continuously or intermittently in the length direction of the fiber.

In another embodiment of the invention, the substance may completely cover the surface of the fiber body, creating an annular surface layer when viewed in cross section.

In another embodiment of the present invention, the above two types of substances can be formed simultaneously on the surface of the same fiber main body, and the form may be intermittently in the length direction of the fiber, or may be formed in a layered manner. It may be arranged in a stacked or parallel manner.

In the present invention, the substance may be applied to each single fiber as described above, but the above-mentioned treatment may be applied to the form of a fiber structure, that is, a woven fabric, a vA material, or a nonwoven fabric. It may be something that is administered.

There are various methods of attachment, such as transferring a film-like surface, vapor deposition or sputtering, or coating or spraying a metal or metal compound with a binder, but in the case of fabric, it is possible to transfer the film. In the case of fibers, vapor deposition or spraying is preferred.

The fibers may be any of the following slit fibrous materials: natural fibers, synthetic fibers, and synthetic films, but materials such as polyamide,
Polyester is easy to process and has excellent durability.

For practical use, heat ray-absorbing material composite fiber alone is sufficient, but in this case it absorbs heat rays and generates high temperatures, providing heat to the human body, for example, but on the contrary, conduction and convection effects Therefore, heat transfer to the outside may easily occur.

In addition, in the case of only a heat ray reflective material composite fiber, it has the effect of reflecting and storing the heat rays built in, but it does not have the effect of absorbing new heat rays, so in this case too, heat transfers to the outside and The temperature will decrease.

Therefore, it is preferable to prevent such a temperature drop, and for example, it is selected to use a fiber made of a composite of both of the above-mentioned substances at the same time, or to use a mixture of heat-retaining and heat-insulating materials. Materials containing a large amount of air are particularly effective as heat-retaining and heat-insulating materials. There are two methods of mixing, stacking and mixing, and either method may be used in the present invention. As such a material, a material with low thermal conductivity is selected, and a material containing air is preferable. Furthermore, it is preferable to have a structure that prevents convection (movement) of this air. Specifically, fibrous substances are mentioned, and fibrous structures such as cotton-like filaments, nonwoven fabrics, and textiles are preferably applied. When these fiber structures are laminated, the purpose can be achieved by applying the composite fiber of the present invention or a fiber structure formed therefrom to the outermost layer. In addition, when mixing, the composite fiber of the present invention and other fibers are mixed.

Mixed spinning, mixed knitting and weaving. In this case, the mixing ratio of composite fibers is preferably at least 20% by weight.

The amount of air in heat-retaining and heat-insulating materials affects the heat-retaining ability, but as a measure of heat-retaining ability, at least
LO is necessary, and the higher it is, the better, but if it is too high, the absorbed heat rays will not reach the human body and only the absorbent fiber material will become hot.

To measure the CLO value, use a heat retention tester manufactured by Ohtsuka Kagaku Seiki Seisakusho to calculate the input heat required to maintain a heater temperature of 40°C with the outside temperature constant, and calculate the amount of heat input to be 0.18°C/kca.
l/nr-hr is shown as ICL, 0.

In addition to preventing conduction and convection, it also prevents radiation, which is another factor in heat transfer, making it even more effective when heat-absorbing fibers are used in combination. Various methods can be considered for the polymerization and lamination, and any method can be employed, but stitching with a sewing machine or the like, or a method using an adhesive or the like is preferable, but depending on the purpose, simply lamination may be used. The polymerization stacking order may be any combination except that the absorbent fiber material is located on the side directly exposed to the hot body. However, in order to increase the durability of the absorbent surface, there is also a method of placing a rough cloth or the like on the outermost layer.

Composite fibers made of heat-absorbing fibers are effective even when mixed with general fibers. If it is at least 20% or more, a heat ray absorption effect will occur.

The composite fiber of the present invention will be explained with reference to the drawings.

FIG. 1 is a diagram showing an example of the composite fiber of the present invention. Cases in which part 1 having a high absorption capacity for average electromagnetic wavelengths of 7 μm or less and part 2 having reflective performance for average electromagnetic wavelengths of 14 μm or more coexist, and cases in which each is combined individually.

(There are three types of Q. Fig. 2 shows a structure in which the base of such composite fiber 3 is laminated with ordinary fiber 114. It may also be a mixture of these.

The heat ray absorbing and heat ray selectively absorbing fibers of the present invention are used as a basic material, and any textile product may be used, but as a general rule, if the surrounding environment has an average electromagnetic wavelength of 7.
It is limited to applications when there is an object that emits wavelengths of μm or less. For example, the products include futons that dry in the sun, mountain climbing equipment, gloves, hats, curtains, clothing for watching sports, and sports clothing.

〔Example〕

Example 1 A heat-absorbing composite fiber was created by mixing chromium oxide powder, an acrylic resin binder, and a solvent with a plain weave fabric made of polyester fiber and having a basis weight of 140 g/rrr, and applying a heat-absorbing thin film surface by spraying. . The heat ray absorption coefficient α at this time was 0.89. As a conduction and convection prevention layer, a sheet of polyester stable fiber with a fineness of 1 denier is made using a card machine and has a basis weight of 200 g/rrr.
A heat-retaining layer was created. The heat retention power of this heat insulation layer is 2 to 3
It is CLO. The heat ray selective absorption composite fiber of the present invention was prepared by simply laminating the two. On the other hand, in order to compare the performance, a conventional fiber without a heat ray absorbing surface was similarly prepared. The conventional plain woven fabric is black.

Both were exposed to a high temperature body with a color temperature of 5000 K in an artificial climate chamber, and the temperature was measured to check the selective absorption performance. The irradiation intensity of the high temperature body is 650kcal/rd-hr.

There are two temperature measurement points: one on the surface of the heat-absorbing fiber material and one on the lower surface of the heat-retaining layer, for a total of four points including the conventional product.

The temperature is 5℃, the humidity is 50%R1 (the results are shown in Table 1, and the results are as shown in Table 1. The heat-selective absorbing composite fiber of the present invention can withstand temperatures of 10℃ or more compared to those using conventional fibers. Become.

Example 2 A heat-absorbing conjugate fiber was prepared by adhering a heat-absorbing thin film containing copper oxide as a main component to a plain weave of polyester filament fabric having a basis weight of 100 g/g using an adhesive.

The heat ray absorption coefficient α at this time was 0.91. transmission.

As a convection prevention layer, a heat retaining layer made of polyester filament having a fineness of 0.8 denier and having a basis weight of 100 g/rrr, a thickness of 5-B, and a heat retaining power of 1.5 CLO was prepared. In addition, polyester filament fabric weight 100g/
A heat-absorbing composite fiber was prepared by bonding an aluminum low-emission thin film surface to a Nl plain weave with an adhesive. The three parts are made of heat-absorbing fiber material.

The thermal layer and the heat ray absorbing fiber material were partially sewn together using a quilting sewing machine in that order to create a heat ray selective absorbing fiber material. At this time, the absorption surface and low-emission surface were exposed to the outside. Similarly,
A conventional fiber material without a heat ray absorption surface and a heat ray low incidence surface was created. Heat retention power 0.8 CL on top of polyurethane foam insulation layer
A knitted fabric of O was placed, and both were placed on top of it. In order to check the absorption and heat retention performance in the same manner as in Example 1, the surface and heat retention conditions were set at a temperature of 10°C, a humidity of 60%, and an irradiation intensity of 570 kcal/rrr-hr. The subsurface temperature of the lower nine sections of the layer was measured. The results are shown in Table 1, and the composite fibers of the present invention have good absorption of heat rays, rapid temperature rise, and do not allow heat to escape.

Example 3 Chromium oxide on polyester staple raw cotton.

A heat-absorbing composite fiber is created by mixing the powder, binder, and solvent and applying a heat-absorbing surface using a spray method, and then mixing it with 55% of non-applied Momen fiber to obtain a fabric weight of 2.
A heat-absorbing composite fiber having a plain weave of 00 g/rrf was prepared. Heat retention power 2.1CL composed of polyester fiber
A heat ray selective absorption composite fiber 3 was made by combining it with a heat retaining layer of O. On the other hand, as a comparative product, a conventional fiber material without a heat ray absorbing surface of the same standard was prepared, and an experiment was conducted under the same conditions as in Example 1. The results are shown in Table 1, and the product of the present invention had a higher absorption capacity and a higher heat retention effect.

(Margins below this page) Example 4 Aluminum was attached to a polyester film by vacuum evaporation to provide a highly reflective surface for heat rays.

Fine chromium oxide powder, an acrylic resin binder, and a solvent were mixed with each other by a spray method to form a thin film on both sides of this. The heat ray absorption coefficient α of this film is 0.90. The emissivity ε was 0.22.

The film was slit to a width of 0.3 mm to create a filament-like composite fiber according to the present invention.

Using this, a jersey knitted fabric of 200 g/rrr was created. On the other hand, a black conventional knitted fabric 1 of the same standard was prepared as a comparative product.

A cotton-like fabric having a heat retention capacity of 2.7 CLO was laminated on both to create a clothing product.

Both were exposed to a high-temperature body with a color temperature of 5000 K in an artificial climate chamber, and the temperature was measured to check the heat ray selective absorption performance.

The irradiation intensity of the high temperature body was 0.75 KW/of·hr, and the temperature measurement points were two points: the surface of the heat ray selective absorption fiber material and the bottom of the cotton-like fabric. The temperature is 5℃ and the humidity is 60%RH.

The results are shown in Table 2, and the fibers using the composite fiber of the present invention reach high temperatures at all positions.

Example 5 Copper oxide powder,
An acrylic resin binder and a solvent were mixed to form a thin film on both sides, and the fiber was slit to a width of 0.5 vna to produce a heat-absorbing composite fiber. A plain woven fabric was prepared by mixing polyester spun yarn with a cotton count of 40 and cotton yarn at a weight ratio of 8:2. For comparison, Fabric 2 of the same standard was made and its heat ray absorption performance was tested.

The temperature was measured using a copper-constantan thermocouple at two points: on the surface of the fiber material and on the surface of the polyurethane foam placed under the fiber material.

The results of an experiment conducted in an artificial climate chamber under the same conditions as in Example 4 are shown in Table 12, and the composite fibers according to the present invention have good absorption of electromagnetic waves and a high temperature.

〔Effect of the invention〕

The heat ray selective absorption composite fiber according to the present invention can absorb radiant energy emitted from high-temperature objects located in the environment, cut off radiant energy from objects that has increased due to absorption or self-heating, and can quickly absorb electromagnetic waves and retain heat. It is possible.

[Brief explanation of drawings]

Figures 1 (A) to (C) show one composite fiber according to the present invention.
It is a figure which shows an example. FIG. 2 is an example of a fiber structure in which the composite fibers shown in FIG. 1 are mixed. DESCRIPTION OF SYMBOLS 1... Heat ray absorption part, 2... Heat ray reflection part, 3... Composite fiber, 4... Fiber.

Claims (12)

[Claims] (1) The fiber body is made of at least one material selected from a heat ray-absorbing material that absorbs electromagnetic waves with an average wavelength of 7 μm or less and a heat-ray reflective material that reflects electromagnetic waves with an average wavelength of 14 μm or more. A composite fiber characterized by being present on at least a part of the surface of the composite fiber. (2) The composite fiber according to claim 1, wherein the heat ray absorbing substance or the heat ray reflecting substance is a metal compound. (3) The composite fiber according to claim 1, wherein the heat ray absorbing substance is a metal oxide. (4) The composite fiber according to claim 1, wherein the heat ray reflective material is a specular metal. (5) At least one substance selected from a heat ray absorbing material that exhibits absorbency for electromagnetic waves with an average wavelength of 7 μm or less and a heat ray reflective material that exhibits reflectivity for electromagnetic waves with an average wavelength of 14 μm or more is on the surface of the fiber body. A fiber structure characterized in that at least a portion of the composite fiber is mixed with other fibers. (6) The fiber structure according to claim 5, which is achieved by a laminated structure using a mixture of the two types of fibers. (7) The fibrous structure according to claim 6, wherein the other fiber is a fiber having a heat retention ability greater than ICLO. (8) The fiber structure according to claim 5, wherein the mixing of the two types of fibers is achieved by blending, blending, or knitting or weaving. (9) The fiber structure according to claim 8, wherein the blending rate of the composite fiber is at least 20% by weight. (10) The fiber structure according to claim 5, wherein the heat ray absorbing substance or heat ray reflecting substance of the composite fiber is a metal compound. (11) The fiber structure according to claim 5, wherein the heat ray-absorbing substance of the composite fiber is a metal oxide. (12) The fibrous structure according to claim 5, wherein the heat-reflective substance of the composite fiber is a mirror-like metal.