JPH1016108A - Heat insulation sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation sheet having excellent heat insulation and continuing the insulation for a long period. SOLUTION: In the heat insulation sheet comprising a base material layer 1, and surface layers laminated on one or both surfaces of the layer 1, the layer 1 is formed of a spun bonding method nonwoven fabric slipped by needle punching and having a density of 0.01 to 0.3g/cm<3> . The layers 2a, 2b are each formed of a spun bonding method nonwoven fabric heat embossed and having a density of 0.1 to 1.5g/cm<3> .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating sheet, and more particularly, to a heat insulating sheet which is excellent in heat insulating properties and whose heat insulating properties are maintained for a long period of time.

[0002]

2. Description of the Related Art Room heaters such as stoves, kotatsu, and hot carpets are used to heat rooms by laying or spreading them on floors or tatami mats. In particular, hot carpets are widely used to spread over a floor or tatami to provide a wide range of heating. Since this hot carpet is spread on a floor or a tatami mat, the contact area with the floor or the tatami mat is large, the loss of heat due to heat transfer from the contact surface increases, and the heating efficiency may be reduced. There is. Therefore, hot carpets are used to cut off heat transfer to the floor or tatami to improve heating efficiency,
It can be spread on the thermal insulation sheet. Conventionally, a sheet made of a blanket, various rugs, a resin foam, a polymer resin sheet, paper, or the like has been used as the heat insulating sheet. Further, a nonwoven fabric having a structure having a heat-resistant resin layer on both sides or one side has been proposed (Japanese Patent Laid-Open No. Hei 6-210803).

[0003]

However, conventional blankets, rugs and the like are difficult to fold and are bulky. Also,
Conventional sheets have the drawback that when laid on these sheets, the hot carpet becomes slippery. Further, in a heat retaining sheet having a structure in which a heat resistant resin layer is provided on both sides or one side of a nonwoven fabric, the base material layer may be densified at the time of manufacturing, and the heat retaining property may be reduced. In addition, they did not yet have sufficient slip prevention properties.

Accordingly, an object of the present invention is to provide a heat-insulating sheet which is excellent in heat-insulating properties and whose heat-insulating properties are maintained for a long period of time.

[0005]

In order to solve the above-mentioned problems, the present invention provides a heat insulating sheet having a base material layer and a reinforcing layer laminated on one or both sides of the base material layer, The base material layer is made of a spunbonded nonwoven fabric having a density of 0.01 to 0.3 g / cm ³ entangled by needle punching, and the reinforcing layer has a heat embossed density of 0.1 g / cm ³ .
There is provided a heat insulating sheet made of spunbonded nonwoven 1-1.5 g / cm ^3.

Hereinafter, the heat retaining sheet of the present invention (hereinafter, referred to as “sheet of the present invention”) will be described in detail.

The sheet of the present invention has a base layer and a reinforcing layer laminated on one or both sides of the base layer. Further, the base material layer or the reinforcing layer may each have only one layer, or may have two or more layers. In addition, it is preferable that the sheet of the present invention, in addition to the base layer and the reinforcing layer, be provided with a slip prevention layer outside the reinforcing layer, since good slip prevention can be obtained. Further, the sheet of the present invention may have a layer having closed cells capable of maintaining voids as needed. For example, it may have a foam layer made of polyethylene, polypropylene, or the like.

[0008] In the sheet of the present invention, the base material layer is a nonwoven fabric produced by a spun bond method and entangled with constituent fibers by a needle punching method. Also,
Since the constituent fibers are entangled with the needles by the needle punching method, the thickness of the constituent fibers is higher than that of the nonwoven fabric or the like formed by the heat embossing method, and the predetermined thickness can be maintained.

The constituent fibers of the nonwoven fabric constituting the base layer include those made of polyolefins such as polypropylene, polyesters, polyacrylates, polyamides, etc., and fibers made of one of these alone may be used. Or a fiber composed of a combination of two or more types.
Among them, excellent in heat resistance and inexpensive,
Nonwoven fabrics composed of fibers made of polypropylene are preferred.

Further, the nonwoven fabric constituting the base material layer has a density of 0.01 to 0.3 g / cm ³ , a high-strength nonwoven fabric can be obtained, and processing is easy. Preferably it is 0.080 to 0.12 g / cm ³ .

The (average) fiber diameter of the constituent fibers of the nonwoven fabric is usually about 2 to 15 denier, preferably about 5 to 10 denier.

Furthermore, the basis weight of this nonwoven fabric is usually 1
A 00~400g / m ^2, in terms secondary processing is easy, and preferably from 100 to 200 g / m ^2.

[0013] Furthermore, the thickness of the nonwoven fabric forming the base material layer is adjusted to form voids that provide a heat retaining effect.
It is preferably 1 to 20 mm, particularly preferably 1 to 4 mm.
mm.

In the sheet of the present invention, the reinforcing layer is provided on one or both sides of the base material layer, and is made of a nonwoven fabric manufactured by a spun bond method and formed by heat embossing. It is in a spot heat bonded state by heat embossing. This heat embossing is usually performed at a temperature of 140 to 160 ° C. and a pressure of 40 ° C.
Performed at ５０50 kg / cm.

The nonwoven fabric constituting the reinforcing layer has a density of 0.09 to 0.20 g / cm ³ , in view of easy processing.
Preferably, it is 0.10 to 0.13 g / cm ³ .

The (average) fiber diameter of the constituent fibers of the nonwoven fabric is usually 2 to 15 denier, and 2 to 10 denier.

Further, the basis weight of this nonwoven fabric is usually 1
It is about ² to 100 g / m ² , and has a reinforcing effect, and is preferably 20 to 50 g / m ^{2 in} that the secondary processing is easy.
m ² .

Further, the thickness of the nonwoven fabric is preferably 0.1 to 1.0 mm, more preferably 0.20 to 0.40 mm, in that secondary processing is easy.

The constituent fibers of the nonwoven fabric constituting the reinforcing layer include those made of polyolefin such as polypropylene, polyester, polyacrylate, polyamide and the like, and fibers made of one of these alone may be used. Further, fibers composed of a combination of two or more types may be used. Among these, a nonwoven fabric composed of polypropylene fibers is preferable because of its excellent heat resistance and low cost.

The thickness of the sheet of the present invention is usually 2 to 5 m.
m. The ratio of the thickness of the reinforcing layer / base material layer is usually about 1/5 to 1/3.

Further, it is preferable that the sheet of the present invention has a slip prevention layer outside the reinforcing layer, because the shift can be effectively prevented. The slip prevention layer is formed on one or both outermost surfaces of the sheet of the present invention.
In addition, the form may be a film, a sheet form, a dot form such as a polka dot pattern, or various forms such as a groove, an irregular shape, a sucker shape, and a composite thereof. It may be in a form that has been done.

The material of the slip prevention layer may be a material having a large static friction coefficient, such as natural rubber, acrylic rubber, synthetic rubber such as olefin rubber, various elastomers, or foams of these rubbers. . Particularly, in the present invention, a layer made of an acrylic rubber-based foam is preferable as the slip prevention layer because it is easy to process and inexpensive. The formation of the slip prevention layer made of the acrylic rubber-based foam is performed by applying an allyl rubber-based foam paint to the outer surface of the reinforcing layer of the sheet of the present invention in a predetermined form by roll coating or the like, and then passing over a heating drum. Then, heating and foaming can be performed. The temperature of the heating drum is usually about 170 to 200C, preferably about 180C. Further, the feeding speed of the sheet of the present invention onto the heating drum is desirably about 10 m / min.

The amount of adhesion of the slip prevention layer is usually
It is about ² to 10 g / m ² , and is preferably about 4 to 8 g / m ^{2 from the} viewpoint that breakage, tearing, and other damages do not occur even if pressure is applied due to the weight of an object placed on the top. Further, the coefficient of friction of the surface of the slip prevention layer is preferably about 0.3 to 0.6.

In the production of the sheet of the present invention, the voids are maintained after laminating the nonwoven fabric forming the base layer, the nonwoven fabric forming the reinforcing layer, and the members forming the layers provided as necessary. And then forming the anti-slip layer on one or both outermost surfaces. The method of integrating the laminated nonwoven fabrics and members is not particularly limited as long as the method can integrate the nonwoven fabrics and members. For example, sewing, a needle punching method, an ultrasonic sealing method, a water jet method, or a method using an adhesive may be used. Among these, since the gap can be maintained and the processing is easy,
A sewing method is preferred. In particular, since processing is easy and can be performed at low cost, a method of straight sewing and integration at 5 inch intervals is preferable, and the sewing form may be any of various forms shown in FIG.

Hereinafter, a configuration example of the sheet of the present invention will be described with reference to FIGS. FIG. 1 shows one configuration example of the sheet of the present invention, which has a three-layer structure having a base layer 1 and reinforcing layers 2a and 2b on both surfaces of the base layer 1.

FIG. 2 shows another example of the sheet of the present invention. The sheet has a base layer 21 and reinforcing layers 22a and 22b on both sides of the base layer 21, and further includes the reinforcing layers 22a and 22b. It has a five-layer structure having slip prevention layers 23a and 23b outside of 22b.

FIG. 3 shows a polyethylene foam 31.
Has base material layers 32a and 32b on both surfaces of the base material layer 3
2a and 32b, reinforcing layers 33a and 33b are provided outside, and further, slip preventing layers 34a and 3
This is a seven-layer structure having 4b.

4 (A) to 4 (D) show a method of laminating and integrating each layer in the sheet of the present invention by sewing, and FIGS. 4 (A) to 4 (D) respectively show (A) substrate layer After laminating non-woven fabrics or other members to be reinforcing layers and other layers arranged as necessary in a predetermined order, sewing them in one direction at a constant interval with a sewing machine, and locking the peripheral edge 41 with a lock sewing machine or the like. (B) After the nonwoven fabric and the members are laminated, they are sewn at an interval in the vertical and horizontal directions so as to be orthogonal to each other, and the peripheral edge 41 is overlocked by a lock sewing machine or the like. (C) After laminating the non-woven fabric and the members, the non-woven fabric and the members are stitched at a constant interval in a diagonal direction to the edge by a sewing machine, and the peripheral edge 41 is locked with a lock sewing machine or the like. (D) After laminating the non-woven fabric and the members, the non-woven fabric and the members are sewn at regular intervals so as to be oblique to the edge and perpendicular to each other, and the peripheral edge 41 is overlocked with a lock sewing machine or the like. The method of sewing and integrating is shown.

The heat retaining sheet of the present invention is not limited to a heat retaining sheet for a hot carpet, and can be used for a packaging material for a heated or frozen food, an electric device such as a kotatsu.

[0030]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples of the present invention, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, the heat retention and the friction coefficient were measured according to the following methods.

The heat retention was measured under the following conditions in accordance with JIS L1096A. Tester: ASTM type heat retention tester Test plate area: 225 cm ² Test plate temperature: 36 ± 0.5 ° C Outside air temperature: about 20 ° C Test time: 60 minutes

The coefficient of friction was measured under the following conditions in accordance with ASTM D1894. Friction force: 200gf Friction target: Aluminum plate

(Example 1) A polypropylene nonwoven fabric (thickness: 1.5 mm, basis weight: 1) manufactured by a spun bond method as a base material layer and entangled with a needle punch
40 g / m ² , density: 0.093 g / cm ³ )
A polypropylene non-woven fabric (thickness: 0.24 m) having a rubber coating applied to the surface as a reinforcing layer on both sides of the non-woven fabric
m, basis weight: 25 g / m ² , density: 0.104 g / cm
³ ) were laminated and sewn at intervals of 5 inches in the pattern shown in FIG. Further, an acrylic rubber-based foamed paint was applied to the outer surfaces of the reinforcing layers on both sides and foamed to form a slip prevention layer, thereby producing a heat insulating sheet having a five-layer structure shown in FIG. About the obtained heat retention sheet, the heat retention rate and the friction coefficient were measured. Table 1 shows the results.

(Example 2) Polypropylene foam (PEF, Toray Industries, Ltd., PEF, thickness: 2.0 mm), polypropylene nonwoven fabric (thickness: 1. 0 mm, weight per unit area: 100 g / m
^2. Density: 0.100 g / cm ³ ), and a polypropylene non-woven fabric (thickness:
0.24 mm, basis weight: 25 g / m ² , density: 0.10
4 g / cm ³ ), and after 5 inches
The pattern was sewn in the pattern shown in FIG. next,
An acrylic rubber foam paint was applied to the outer surfaces of the reinforcing layers on both sides and foamed to form a slip prevention layer, thereby producing a seven-layer heat insulating sheet shown in FIG. About the obtained heat retention sheet, the measurement of the heat retention rate was performed. Table 1 shows the results.

Comparative Example 1 As shown in FIG.
Polypropylene nonwoven fabric manufactured by the spun bond method as No. 1 (thickness: 2.0 mm, basis weight: 200 g / m
^2, density: 0.100 g / cm ³⁾ with, on both sides of the nonwoven fabric, polyethylene film (thickness: 35 [mu] m, density: 0.916 g / cm ³⁾ was laminated to 52a and 52 b, a three-layer structure sheet Was manufactured. The obtained sheet was measured for the heat retention and the coefficient of friction.
Table 1 shows the results.

(Comparative Example 2) The heat retention rate of a dry short-fiber card knee pan nonwoven fabric was measured. Table 1 shows the results.

[0037]

[0038]

The heat retaining sheet of the present invention has excellent heat retaining properties, its heat retaining properties are maintained for a long period of time, and when laid under a heating element such as a hot carpet,
The heat transfer from the hot carpet or the like to the floor or tatami mats can be blocked to improve the heat retaining effect of the hot carpet or the like. Therefore, it is effective for saving power consumption of a hot carpet or the like. It is also effective for preventing slippage and displacement of the hot carpet from the floor and tatami mats.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view showing a configuration example of a heat retaining sheet of the present invention.

FIG. 2 is a partially cutaway sectional view showing another configuration example of the heat retaining sheet of the present invention.

FIG. 3 is a schematic cross-sectional view showing another configuration example of the heat retaining sheet of the present invention.

FIGS. 4A to 4D are schematic plan views illustrating a method of laminating and integrating the heat retaining sheet of the present invention by sewing. FIGS.

FIG. 5 is a schematic sectional view showing a structural example of a sheet manufactured in a comparative example.

[Explanation of symbols]

 Reference Signs List 1 base layer 2a, 2b reinforcing layer 21 base layer 22a, 22b reinforcing layer 23a, 23b slip prevention layer 31 polyethylene foam 32a, 32b base layer 33a, 33b reinforcing layer 34a, 34b reinforcing layer 35a, 35b slip preventing layer 41 Peripheral edge 51 Base layer 52a, 52b Polyethylene film

Claims (4)

[Claims] 1. A heat retaining sheet having a base material layer and a reinforcing layer laminated on one or both sides of the base material layer, wherein the base material layer has a density of 0.1% entangled by needle punching.
A spunbond nonwoven fabric having a density of 0.1 to 0.3 g / cm ³ , wherein the reinforcing layer has a heat-embossed density of 0.1 to 0.3 g / cm ³ ;
Thermal insulation sheet made of spunbond non-woven fabric of 1.5g / cm ^3. 2. The heat insulating sheet according to claim 1, wherein the base material layer and the reinforcing layer are laminated and integrated by sewing, needle punching, ultrasonic sealing, water jetting, or a method using an adhesive. . 3. The base material layer has a thickness of 1 to 20 mm,
The thickness of the reinforcing layer is 0.1 to 1.0 mm.
Or the heat retention sheet of 2. 4. The heat retaining sheet according to claim 1, further comprising a slip prevention layer made of a rubber-based foam outside the reinforcing layer.