阅读说明：本技术 包含气凝胶的复合绝热片材 (Composite thermal insulation sheet comprising aerogel ) 是由 吴景实 李悌均 韩炳旭 全容奭 朴祥佑 金重年 于 2018-08-21 设计创作，主要内容包括：本发明涉及一种包含气凝胶的复合绝热片材及其制造方法。本发明提供了一种超薄气凝胶复合片材,该超薄气凝胶复合片材具有低粉尘、高强度和高绝热特性,从而具有提高的用于电子设备的实用性。(The present invention relates to a composite thermal insulation sheet comprising aerogel and a method of manufacturing the same. The present invention provides an ultra-thin aerogel composite sheet having low dust, high strength, and high thermal insulation characteristics, thereby having improved practicality for electronic devices.)

1. A composite insulation sheet comprising:

an aerogel sheet;

a sol-impermeable coating formed on one surface of the aerogel sheet; and

one or more functional layers formed on the other surface of the aerogel sheet.

2. The composite thermal insulation sheet of claim 1, wherein the coating comprises one or more selected from the group consisting of Polyamide (PA), Polyethylene (PE), polyethylene terephthalate (PET), Polyimide (PI), and silicon.

3. The composite insulation sheet of claim 1, wherein the sol comprises one or more selected from the group consisting of zirconia, yttria, hafnia, alumina, titania, ceria, silica, magnesia, calcia, magnesium fluoride, and calcium fluoride.

4. The composite thermal insulation sheet according to claim 1, wherein the functional layer exhibits one or more functions selected from the group consisting of heat diffusion, insulation, sound absorption, vibration resistance, water impermeability, and permeability to water vapor.

5. The composite insulation sheet of claim 1, wherein the sheet is inorganic fibers, organic fibers, or a combination thereof.

6. The composite insulation sheet of claim 1, wherein the sol-impermeable coating has a thickness of 30 μ ι η or less.

7. The composite insulation sheet of claim 1, wherein the aerogel sheet has a thickness of 2 millimeters or less.

8. The composite insulation sheet of claim 1, wherein the composite insulation sheet has a thickness of 3 millimeters or less.

9. A method of making a composite thermal insulation sheet, the method comprising:

forming a sol-impermeable coating on one surface of a fibrous sheet;

impregnating the other surface of the fiber sheet with a sol and a catalyst;

forming a wet gel sheet by gelling the impregnated sheet;

forming an aerogel sheet by drying the wet gel sheet; and

forming one or more functional layers on the aerogel sheet.

10. The method of claim 9, wherein said composite insulation sheet comprises an aerogel sheet having a sol-impermeable coating formed on one surface thereof and a functional layer formed on the other surface thereof.

11. The method of claim 9, wherein the sol-impermeable coating is formed on one surface of the fibrous sheet by placing fibers on a coating to which a release paper is attached and then performing heat treatment.

12. The method of claim 11, further comprising removing the release paper from the coating after gelation is complete.

Technical Field

The present invention relates to composite thermal insulation sheets comprising aerogel and methods of making the same.

Background

Electronic products such as notebook computers, OLEDs, and TVs have hot spots generated by heat sources, so that consumer perceptibility may be deteriorated due to local heat release on the surface of the device. In addition, when heat is improperly diffused to the outside using a simple insulation material, excessively accumulated heat may cause system failure, shorten the life span of a product, or cause explosion or fire in a severe case. Various kinds of heat insulating materials have been applied to solve such problems caused by heat generation. However, an optimum thermal insulating material that is thin and excellent in thermal insulating performance has not been developed so far. Therefore, various studies and technical developments are still being made.

In order to solve such typical problems, the present invention has been made in an attempt to solve the above problems by applying aerogels that are attracting attention as highly efficient heat insulating materials.

Aerogels are highly porous materials composed of nanoparticles, having high porosity, specific surface area, and low thermal conductivity, and thus are attracting attention as efficient thermal insulation materials, sound insulation materials, and the like.

Meanwhile, since aerogel has very low mechanical strength due to its porous structure, an aerogel composite obtained by impregnating fibers such as inorganic fibers or organic fibers, which are conventional thermal insulation fibers, with aerogel is prepared and used. However, such aerogel composite materials have poor adhesion between fibers and aerogel particles, so that aerogel particles are separated during processing such as cutting and bending, resulting in generation of dust and deterioration in durability, which may cause damage to equipment when used as a heat insulating material for electronic products and the like.

Accordingly, in order to solve the above problems, the present invention provides an aerogel composite sheet having low dust, high strength, and high heat insulation characteristics to improve its applicability to electronic devices.

[ Prior art documents ]

(patent document 1) US 8,021,583B 2(2011, 9 months and 9 days)

Disclosure of Invention

Technical problem

An aspect of the present invention provides an ultra-thin composite thermal insulation sheet having low dust, high strength, and high thermal insulation characteristics so as to be used for electronic devices, and a method of manufacturing the same.

Technical scheme

According to one aspect of the present invention, there is provided a composite thermal insulation sheet comprising an aerogel sheet, a sol-impermeable coating formed on one surface of the aerogel sheet, and one or more functional layers formed on the other surface of the aerogel sheet.

According to another aspect of the present invention, there is provided a method of manufacturing a composite thermal insulation sheet, the method comprising: forming a sol-impermeable coating on one surface of a fibrous sheet; impregnating the other surface of the fiber sheet with a sol and a catalyst; forming a wet gel sheet by gelling the impregnated sheet; forming an aerogel sheet by drying the wet gel sheet; and forming one or more functional layers on the aerogel sheet.

Advantageous effects

According to the composite thermal insulation sheet of the present invention, dust generation is reduced by the sol-impermeable coating layer formed on one surface, so that high thermal insulation efficiency and processing convenience can be provided.

Further, according to the composite thermal insulation sheet of the present invention, the mechanical strength is improved by the coating layer, so that the durability can be improved.

Further, according to the composite thermal insulation sheet of the present invention, other necessary functions can be ensured by the functional layer.

Drawings

The following drawings attached hereto illustrate preferred embodiments of the present invention by way of examples and together with the detailed description of the present invention given hereinafter serve to further understand the technical concept of the present invention, and therefore, the present invention should not be construed as limited solely by the matters in the drawings.

Fig. 1 is a graph showing the thermal conductivity of the composite thermal insulation sheets of examples and comparative examples.

Detailed Description

Hereinafter, the present invention will be described in more detail to facilitate understanding of the present invention. In this case, it should be understood that the words or terms used in the specification and claims should not be construed as having meanings defined in common dictionaries. It is to be further understood that the words or terms are to be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the technical spirit of the present invention, based on the principle that the inventor may properly define the meaning of the words or terms in order to best explain the present invention.

In general, electronic products may have hot spots generated by heat sources, so that quality may be deteriorated due to local heat release on the surface of the device. Therefore, the present invention is intended to use an aerogel sheet as a highly efficient thermal insulation material.

However, the aerogel sheet has poor adhesion between the fibers and the aerogel, so that aerogel particles are separated during processing such as cutting and bending, and the aerogel sheet has poor strength resulting in poor durability. Therefore, its application as a heat insulating material to electronic products and the like is limited.

Accordingly, an aspect of the present invention provides an ultra-thin composite thermal insulation sheet having low dust, high strength and high thermal insulation characteristics so as to be widely used in electronic products, and a method of manufacturing the same.

Hereinafter, the composite thermal insulation sheet of the present invention and the method of manufacturing the same will be described in detail.

According to one aspect of the present invention, there is provided a composite thermal insulation sheet comprising an aerogel sheet, a sol-impermeable coating formed on one surface of the aerogel sheet, and one or more functional layers formed on the other surface of the aerogel sheet.

In order to reduce dust generation, which is a typical problem, the composite thermal insulation sheet of the present invention is characterized by introducing a sol-impermeable coating on one surface of the aerogel sheet.

In particular, the coating comprises one or more selected from the group consisting of Polyamide (PA), Polyethylene (PE), polyethylene terephthalate (PET), Polyimide (PI) and silicon.

The coating is characterized in particular by being sol-impermeable. When the sol is impregnated into the organic or inorganic fibers during the preparation of the aerogel sheet, the coating of the present invention prevents the sol from penetrating the fibers and flowing outward, thereby preventing the aerogel from being exposed to the surface of the aerogel sheet and achieving low dust characteristics. Meanwhile, the other surface (on which the coating layer is not formed) may prevent the aerogel from being exposed to the outside by the functional layer to be described.

In addition, the coating can be used to supplement the mechanical strength of the aerogel sheet (which is low due to the porous structure of the aerogel). The coating can improve durability by increasing the mechanical strength of the composite thermal insulation sheet.

Meanwhile, the thickness of the sol-impermeable coating layer of the present invention is 30 μm or less, more particularly 10 to 20 μm. When the thickness of the sol impermeable coating layer is greater than the above range, the thermal insulation performance of the composite thermal insulation material may be deteriorated and its application to electronic products requiring an ultra-thin thermal insulation material may be limited. On the other hand, when the thickness is less than the above range, the effect of improving the mechanical strength is insignificant, so that the durability may be poor.

In the present invention, the material capable of forming a sol may include one or more inorganic materials selected from zirconia, yttria, hafnia, alumina, titania, ceria, silica, magnesia, calcia, magnesium fluoride, and calcium fluoride.

Further, the sol may include silicon-containing alkoxide-based compounds, specifically, tetraalkyl silicates such as tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), prehydrolyzed TEOS, methyl triethyl orthosilicate, dimethyl diethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetra-sec-butyl orthosilicate, tetra-tert-butyl orthosilicate, tetrahexyl orthosilicate, tetracyclohexyl orthosilicate, and tetradodecyl orthosilicate.

Further, the alcohol that can be used for producing the silica sol of the present invention may be specifically monohydric alcohols such as methanol, ethanol, isopropanol, and butanol; or polyhydric alcohols such as glycerin, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, and sorbitol, and any one or a mixture of two or more thereof may be used. When considering its miscibility with water and aerogels, the alcohol may be a monohydric alcohol having 1 to 6 carbon atoms, such as methanol, ethanol, isopropanol, and butanol. The above-mentioned alcohol (polar organic solvent) may be used in an appropriate amount in view of the degree of hydrophobicity of the finally produced silica aerogel while promoting the surface modification reaction.

In addition, the composite insulation sheet of the present invention can include one or more functional layers on another surface of the aerogel sheet.

Meanwhile, when an electronic product cannot properly diffuse generated heat to the outside by using a simple heat insulating material, excessively accumulated heat may cause system malfunction, shorten the service life of the product, or cause explosion or fire in severe cases.

Accordingly, the present invention provides a composite thermal insulation layer in which a functional layer is laminated on another surface on which a sol-impermeable coating layer of the composite thermal insulation sheet is not formed, thereby having excellent thermal insulation properties and preventing damage to equipment due to no generation of dust. Furthermore, the composite thermal insulation layer according to the present invention has a structural feature in which heat accumulation in the equipment is prevented due to thermal insulation, thereby preventing damage to the equipment.

Specifically, the functional layer may exhibit one or more functions selected from heat diffusion, insulation, sound absorption, vibration resistance, water impermeability, and permeability to water vapor, and the composite heat insulating sheet of the present invention may include a functional layer that is not limited to the above functions and may exhibit functions required in electronic products to which it is to be used.

Meanwhile, when the functional layer is impermeable to water, the composite heat insulation sheet of the present invention can prevent water from penetrating into the electronic component to prevent damage to the electronic component, and when the functional layer is permeable to water vapor, the electronic component can be prevented from being damaged due to the prevention of water vapor from condensing in the electronic component. The layer that is impermeable to water and permeable to water vapor may comprise a cellulosic material.

In the aerogel sheet included in the composite heat insulation sheet of the present invention, inorganic fibers, organic fibers, or a combination thereof may be used for the sheet.

More specifically, the sheet may be a film, a sheet, a mesh, a fiber, a porous body, a foam, a nonwoven body, or a laminate of two or more layers thereof. Further, a surface roughness or a patterned surface roughness may be formed on the surface thereof according to the use. The sheet may be a fiber capable of further improving thermal insulation performance by containing a space or void through which the sol can be easily embedded in the sheet. In addition, the sheet of the present invention may preferably have low thermal conductivity.

Specifically, the fiber sheet useful in the present invention may be polyamide, polybenzimidazole, aramid, acrylic resin (acryl resin), phenol resin, polyester, polyether ether ketone (PEEK), polyolefin (e.g., polyethylene, polypropylene, or a copolymer thereof, etc.), cellulose, carbon, cotton, wool, hemp, nonwoven fabric, glass fiber, or ceramic wool.

Meanwhile, the thickness of the aerogel sheet of the present invention is 3mm or less, specifically 2 mm or less, more specifically 1 mm or less. When the thickness of the aerogel sheet is greater than the above range, application thereof to electronic products requiring an ultra-thin thermal insulation material may be limited, and when the thickness is less than the above range, durability may be deteriorated due to extremely low mechanical strength and thermal insulation performance may be poor.

Further, the composite thermal insulation sheet of the present invention has a thickness of 3mm or less, specifically 2 mm or less, more specifically 1 mm or less. When the thickness of the composite thermal insulation sheet is greater than the above range, it may be difficult to apply to electronic products requiring ultra-thin thermal insulation materials, and when the thickness is less than the above range, processability may be deteriorated.

Further, the present invention provides a method of manufacturing the composite thermal insulation sheet.

Specifically, the method of making the composite thermal insulation sheet of the present invention comprises: forming a sol-impermeable coating on one surface of a fibrous sheet; impregnating the other surface of the fiber sheet with a sol and a catalyst; forming a wet gel sheet by gelling the impregnated sheet; forming an aerogel sheet by drying the wet gel sheet; and forming one or more functional layers on the aerogel sheet.

More specifically, the sol-impermeable coating layer may be formed by placing fibers on a coating layer having a release paper attached thereto and then performing heat treatment.

In this case, the release paper is a material that protects an adhesive surface by being in contact with the adhesive surface of an adhesive tape, an adhesive paper, a label, or the like, and is peeled off at the time of use to complete its use.

In the method of forming the sol-impermeable coating of the present invention, the release paper is used to fundamentally prevent the aerogel from being exposed to the surface of the aerogel sheet.

Specifically, in the case where a coating layer is formed on one surface of a fiber sheet in the absence of a release paper and then a solution containing a sol and a catalyst is impregnated on the other surface of the fiber sheet, when the solution is excessive to the extent that the fiber sheet cannot be impregnated with all the solution, an aerogel is formed on the surface of the coating layer from the sol overflowing the fiber sheet, so that the coating layer is contaminated, and in this case, the coating layer cannot sufficiently prevent dust generation.

Therefore, in the method of manufacturing the composite thermal insulation sheet of the present invention, a release paper containing a coating material is prepared, and then fibers are placed on the coating material, followed by heat treatment to form a coating layer on one surface of the fiber sheet. Next, the release paper attached to the coating layer is removed after the gelation is completed to prevent the surface of the coating layer from being contaminated.

Subsequently, the sol and the catalyst are impregnated into the other surface of the fiber sheet, and the impregnated sheet is gelled to form a wet gel sheet.

The catalyst of the present invention promotes gelation by raising the pH of the sol, and specifically, a basic catalyst can be used.

The basic catalyst may be an inorganic base such as sodium hydroxide and potassium hydroxide; or an organic base such as ammonium hydroxide. However, in the case of an inorganic base, metal ions contained in the compound may coordinate with the Si — OH compound. Therefore, organic bases may be preferred. Specifically, the organic base may be ammonium hydroxide (NH)₄OH), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), methylamine, ethylamine, isopropylamine, monoisopropylamine, diethylamine, diisopropylamine, dibutylamine, trimethylamine, triethylamine, triisopropylamineTributylamine, choline, monoethanolamine, diethanolamine, 2-aminoethanol, 2- (ethylamino) ethanol, 2- (methylamino) ethanol, N-methyldiethanolamine, dimethylaminoethanol, diethylaminoethanol, triethanolamine, 2- (2-aminoethoxy) ethanol, 1-amino-2-propanol, triethanolamine, monopropanolamine, or dibutanolamine, and any one or a mixture of two or more thereof may be used. More specifically, the base of the present invention may be ammonium hydroxide (NH)₄OH)。

Meanwhile, the present invention may further include an aging step in which the silica gel is maintained at a suitable temperature so that chemical changes thereof can be completely accomplished to improve mechanical stability, and thereafter, the present invention may further include a surface modification step in which the surface of the gel is hydrophobized to inhibit absorption of moisture in the air, thereby maintaining low thermal conductivity.

The wet gel sheet can then be dried to form an aerogel sheet, which can be done by atmospheric drying or supercritical drying.

Finally, one or more functional layers can be formed on the aerogel sheet, thereby forming a composite insulation sheet comprising an aerogel sheet having a sol-impermeable coating formed on one surface thereof and a functional layer formed on the other surface thereof.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.