JP2019127961A - Heat insulation sheet and manufacturing method thereof - Google Patents

Abstract

To obtain a heat insulation sheet excellent in insulation property and adiabaticity, and capable of securing a predetermined distance even in a case where pressure is applied.SOLUTION: A heat insulation sheet 11 comprises: a fiber sheet 12 having a space therein; a low compression region 13 provided on at least a part of the fiber sheet 12, and provided across a first surface of the fiber sheet 12 and a second surface opposite to the first surface; and silica xerogel carried in the space other than the low compression region 13 in the fiber sheet 12. The low compression region 13 is configured such that a compression ratio at the time of applying pressure of 0.7 MPa is equal to or less than 5%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat insulating sheet used as a heat insulating measure and a method for manufacturing the same.

  In recent years, measures for heat insulation have been increasingly required for the energy efficiency of various devices. For this reason, various heat insulating materials are used. As a typical example thereof, glass wool, urethane foam, or a heat insulating sheet in which silica xerogel is supported on a non-woven fabric can be mentioned.

  As prior art document information related to the invention of this application, for example, Patent Document 1 is known.

JP, 2011-136859, A

  However, some devices apply pressure to the heat insulating material, but when the pressure is applied to the heat insulating material to be compressed, the heat insulating performance is deteriorated. Therefore, there is a demand for a heat insulating sheet that hardly deteriorates the heat insulating performance even when pressure is applied.

  In order to solve the above problems, the present invention provides a fiber sheet having a space inside and a part of the fiber sheet, and is provided from the first surface of the fiber sheet to the second surface opposite to the first surface. The low compression region and a silica xerogel supported in a space other than the low compression region of the fiber sheet, wherein the low compression region has a compressibility when a pressure of 0.7 MPa is applied. The heat insulation sheet is configured to have a value of 5% or less.

  By comprising as mentioned above, while being able to obtain the heat insulation sheet excellent in insulation and heat insulation, even if a pressure is applied from both sides, the heat insulation sheet which a heat insulation performance does not deteriorate easily can be obtained.

Cross section of heat insulation sheet in one embodiment of the present invention Top view of heat insulation sheet in one embodiment of the present invention The top view of another heat insulation sheet in one embodiment of the present invention

  Hereinafter, the heat insulation sheet in one embodiment of the present invention is explained, referring to drawings.

  FIG. 1 is a sectional view of a heat insulating sheet in one embodiment of the present invention, and FIG. 2 is a plan view thereof.

The heat insulation sheet 11 is comprised from the fiber sheet 12 which has space inside, and the silica xerogel carry | supported by the space of the fiber sheet 12, and thickness is about 3 mm. Fiber sheet 1
2 is made of glass fibers having an average fiber thickness of about 10 μm, and the proportion of space in the fiber sheet 12 is about 90%. The inner space of the fiber sheet 12 is filled with silica xerogel (not shown). Since this silica xerogel has a nano-sized space inside, the thermal conductivity of the portion filled with this silica xerogel is 0.018 to 0.024 W / m · K, and the thermal conductivity of air. It is smaller than that. This silica xerogel is a broad xerogel in a state where the gel is dried, and it may be obtained not only by ordinary drying but also by methods such as supercritical drying and freeze drying.

  Usually, a heat insulating sheet having such a structure is harder to be compressed than urethane foam, glass wool, etc., but when a pressure of 0.7 MPa is applied, it is compressed to 70% to 90% of the original thickness. . In this case, the thermal conductivity itself does not deteriorate so much, but the heat insulation performance deteriorates as the thickness decreases.

  On the other hand, the low compression area | region 13 is provided in the center part of the heat insulation sheet 11 from one surface to the other surface. In the low compression area 13, the internal space of the fiber sheet 12 is filled with the epoxy resin, so that the compression rate when a pressure of 0.7 MPa is applied is 5% or less.

  By comprising in this way, even if a pressure is applied to a part of heat insulation sheet 11, it can prevent being compressed over the whole heat insulation sheet 11 by supporting in the low compression area | region 13. FIG. This can prevent the thermal insulation performance from deteriorating.

  The cross-sectional shape of the low compression region 13 is a shape that spreads from one surface to the other surface. By doing in this way, the surface with a narrow cross-sectional shape can contact | abut to the direction where temperature tends to become higher, and it can make it easier to obtain the heat insulation effect.

  Here, the compression ratio is a value of (t0−t1) / t0 when the thickness in a state where pressure is removed after applying a pressure of 0.7 MPa to a sheet having a thickness of t0 is a percentage. It shows what was displayed.

  Further, the region filled with silica xerogel is in a state where it is difficult for the adhesive or the like to adhere thereto. On the other hand, an adhesive material or the like can be applied to the portion where the low compression region 13 is exposed. Therefore, by providing an adhesive material in the low compression region 13, the heat insulating sheet 11 that can be temporarily fixed and easily assembled can be obtained.

  In FIG. 2, the low compression region 13 is provided only in the central portion of the heat insulating sheet 11, but the low compression region 13 may be provided in the central portion and the peripheral portion as shown in FIG. Further, as shown in FIG. 3B, it may be provided so as to surround an annular portion that is not the low compression region 13. Further, it may be formed in a cross shape as shown in FIG. Further, as shown in FIG. 3D, these may be divided and combined.

  The low compression region 13 is less thermally insulating than the region filled with silica xerogel. For this reason, the proportion of the low compression region 13 in the heat insulating sheet 11 is preferably small. However, if the ratio becomes too small, it becomes difficult to withstand pressure. Therefore, it is desirable that the ratio of the low compression region 13 to the heat insulating sheet 11 is 5% or more and 30% or less.

  Next, the manufacturing method of the heat insulation sheet | seat in one embodiment of this invention is demonstrated.

  First, a fiber sheet 12 made of glass fiber and having a thickness of about 3 mm is prepared.

  Next, epoxy resin is filled in the internal space of a part of the fiber sheet 12 and cured. The cured epoxy resin has a compression ratio of 5% or less when a pressure of 0.7 MPa is applied, and is filled from one side to the other side.

  As a method for filling an epoxy resin into a part of the internal space of the fiber sheet 12, for example, a liquid epoxy resin placed in a cylinder can be injected into the internal space of the fiber sheet 12 through a needle pierced into the fiber sheet 12. The needle stuck near one surface of the fiber sheet 12 is injected while being pulled out to the other surface. At this time, as the tip of the needle approaches the other surface, by adjusting so as to reduce the injection pressure, the cross section of the region filled with the epoxy resin is formed so as to spread from the other surface to the one surface. Can.

  Next, the fiber sheet 12 is immersed in a sol solution formed by adding hydrochloric acid to, for example, an aqueous solution of sodium silicate, and the sol solution is impregnated into the internal space of the fiber sheet 12. At this time, the sol solution does not enter the region filled with the epoxy resin, and the internal space of the fiber sheet 12 in other regions is filled with the sol solution. The sol solution is gelled, hydrophobized, and dried to fill the inner space of the fiber sheet 12 with silica xerogel to obtain the heat insulating sheet 11.

  In the heat insulating sheet 11 produced in this manner, the area filled with the epoxy resin is an area which is much more difficult to compress than the area filled with the silica xerogel, and this area is referred to as a low compression area 13.

  Thus, by providing the low compression area | region 13 in a part of heat insulation sheet 11, even if a pressure is applied to a part of heat insulation sheet 11, it is compressed over the heat insulation sheet 11 whole by supporting in the low compression area | region 13. Can be prevented. This can prevent the thermal insulation performance from deteriorating.

  Furthermore, by changing the arrangement of the needles, a low compression region is easily formed in a desired shape, such as providing a low compression region in the central portion and the peripheral portion, surrounding a circular non-low compression region, or forming a cross shape. be able to.

  Although the heat insulation sheet may be used as it is, it is preferable to provide a protective layer on the surface so that the silica xerogel does not separate.

  The heat insulating sheet and the manufacturing method thereof according to the present invention can obtain a heat insulating sheet that is hard to be compressed even when pressure is applied and has little deterioration in heat insulating performance, and is installed, for example, so as to be sandwiched between an oil pan of an automobile and an outer wall of an automobile motor. It is useful as a heat insulation sheet of the place where the compressive force is applied.

11 insulation sheet 12 fiber sheet 13 low compression area

Claims (9)

A fiber sheet having a space therein, a low compression region provided in a part of the fiber sheet and extending from a first surface of the fiber sheet to a second surface opposite to the first surface; and the fiber Silica xerogel supported in a space other than the low compression region of the sheet, wherein the low compression region has a heat insulation ratio of 5% or less when a pressure of 0.7 MPa is applied. Sheet. The heat insulation sheet according to claim 1, wherein a compression ratio when applying a pressure of 0.7 MPa in a region other than the low compression region is 10% or more and 30% or less. The heat insulating sheet according to claim 1, wherein a cross-sectional shape of the low compression region is a shape that spreads from the first surface to the second surface. The heat insulating sheet according to claim 1, wherein the low compression region is obtained by impregnating and curing a thermosetting resin to the fiber sheet. The said low compression area | region is a heat insulation sheet of Claim 1 provided in the center part of the said heat insulation sheet. The heat insulating sheet according to claim 5, wherein the low compression region is provided in a peripheral portion and a central portion of the heat insulating sheet. The heat insulation sheet of Claim 1 which made the ratio which occupies for the said heat insulation sheet of the said low compression area | region 5% or more and 30% or less. Preparing a fiber sheet having a space inside, and injecting a thermosetting resin at a predetermined location of the fiber sheet from a first surface of the fiber sheet to a second surface opposite to the first surface And a step of curing the thermosetting resin, and immersing the fiber sheet obtained by curing the thermosetting resin in a predetermined sol solution, in a space other than the region where the thermosetting resin is provided on the fiber sheet. A step of impregnating xerogel to obtain a heat insulating sheet, and a method for producing the heat insulating sheet. The thermosetting resin is injected using a needle, and by adjusting the injection amount according to the height of the fiber sheet, the cross-sectional shape of the thermosetting resin is applied from the first surface to the second surface. The manufacturing method of the heat insulation sheet of Claim 8 made into the shape which spreads.