JPS5837902B2 - Porous material with excellent water resistance - Google Patents

Description

【発明の詳細な説明】 この発明は、連続押出し発泡成形法によって実際に使用
される製品の厚さにほぼ一致する厚みで製造される肉厚
を１０〜３００ｍｖｔの合威樹脂平板状多孔質体であっ
て、その厚さ方向に所定の密度分布並に気泡径分布を有
した多孔質体に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a flat plate-shaped porous body of Hewei resin with a wall thickness of 10 to 300 mvt, which is manufactured by continuous extrusion foam molding to a thickness that almost matches the thickness of a product actually used. The present invention relates to a porous body having a predetermined density distribution and cell size distribution in its thickness direction.

一般にポリスチレン、ポリエチレン、ポリウレタン、ポ
リ塩化ビニル等の呼称で代表される合成樹脂の独立気泡
構造の多孔質体は、そのものの持つ疎水性、耐水性、断
熱性能がめでられて、例えば構築物の断熱材に広く用い
られている。Porous materials with a closed cell structure made of synthetic resins, generally represented by names such as polystyrene, polyethylene, polyurethane, and polyvinyl chloride, are known for their hydrophobicity, water resistance, and heat insulation performance, and are used as insulation materials for buildings, for example. widely used.

中でも耐水性に優るポリスチレン樹脂、ポリエチレン樹
脂を主戒分とする多孔質体は、水に浸漬された状態及ひ
又は、温度差により多孔質体両表面間に水蒸気圧差が生
じる状態に置かれる屋上断熱、地下蓄熱槽の断熱等に用
いられることもある。Among them, porous bodies mainly made of polystyrene resin and polyethylene resin, which have excellent water resistance, are used on rooftops where they are immersed in water or where a temperature difference causes a water vapor pressure difference between the two surfaces of the porous body. It may also be used for heat insulation, insulation of underground heat storage tanks, etc.

従来の合成樹脂多孔質体は、上述の如き過酷な条件下で
数年間使用されるとき吸水率が体積パーセントで５〜１
０％にも達してしまい結果的に多孔質が保有する断熱性
能が発揮できなくなるという欠点がある。Conventional synthetic resin porous materials have a water absorption rate of 5 to 1% by volume when used for several years under the above-mentioned harsh conditions.
There is a drawback that the heat insulating properties of porous materials cannot be exhibited as a result of reaching 0%.

本発明者等はこの欠点の解消を多孔質体の断熱性能の向
上をも加味して図ることを考えた。The present inventors considered an attempt to eliminate this drawback by also taking into account improvement in the heat insulation performance of the porous body.

一般に、合戒樹脂多孔質の断熱特性は、同一条件下の比
較では、気泡径が小さい程、密度が小さい程、断熱性能
が向上すると考えられており、従って、熱伝播が、伝導
伝播、対流伝播が支配的である領域では、より小径気泡
の、より低密度多孔質を得ることが、理論上は多孔質の
断熱性能の向上につながることになると云われている。In general, it is believed that when comparing the heat insulating properties of porous resin under the same conditions, the smaller the bubble diameter and the lower the density, the better the heat insulating performance becomes. It is said that in a region where propagation is dominant, obtaining a porous structure with smaller diameter bubbles and a lower density will theoretically lead to an improvement in the heat insulating performance of the porous structure.

しかしながら現実、ことに合成樹脂の連続押出し発泡威
形にあっては、例えば密度２ ５ ｋｇ／ ｍ”を超え
て小さい多孔質体を、０． １ ｍｍ未満の小径気泡状
態で得ることは困難である。However, in reality, especially when it comes to continuous extrusion foaming of synthetic resins, it is difficult to obtain small porous bodies with a density of more than 25 kg/m'' in the form of small-diameter cells of less than 0.1 mm. be.

この理由は小径気泡化方向の多孔質体密度の低密度化は
、気泡数を多くすることが至上条件になるのに対し、気
泡数を密度低下に必要なだけ増加させることが極めて困
難だからである。The reason for this is that while increasing the number of cells is the ultimate condition for reducing the density of the porous material in the direction of small-diameter cells, it is extremely difficult to increase the number of cells to the extent necessary to reduce the density. be.

即ち、一般に気泡の形或は核剤等の使用でできた気泡核
を或長させて所定の径寸法にするのであるが、核剤量、
の過量の使用は生じた気泡核の成長を阻害し、結果的に
小径気泡になっても密度の低下に継がらないし、核剤量
を減量調整して気泡核の戒長を図ろうとすると、気泡核
の成長が不均一となり気泡相互が吸収合体して、気泡数
を減じ結局、中〜犬径気泡の低密度品になるか、或は小
径気泡の高密度品になってしまう現象が生じるからであ
る。That is, in general, the bubble shape or the bubble core formed by using a nucleating agent or the like is lengthened to a predetermined diameter size, but the amount of the nucleating agent,
The use of an excessive amount of nucleating agent inhibits the growth of the resulting bubble nuclei, and even if the bubbles become small in diameter, this does not lead to a decrease in density. The growth of bubble nuclei becomes uneven, and the bubbles absorb each other and coalesce, reducing the number of bubbles, resulting in a low-density product with medium to small-diameter bubbles, or a high-density product with small-diameter bubbles. It is from.

その上に小径気泡・低密度化の方向は、気泡膜を薄肉化
することになることから発泡或形の過程での気泡の連通
化現象が生じ易く独立気泡に富む多孔質体が得難い問題
もが併発する等、押出発泡成形法で独立気泡構造の小径
気泡・低密度多孔質体を得ることは難カルい技術とされ
ている。In addition, the direction of smaller diameter cells and lower density means that the cell membrane is made thinner, which tends to cause the bubbles to become interconnected during the foaming or shaping process, making it difficult to obtain a porous material rich in closed cells. It is considered to be a difficult technique to obtain a small-diameter, low-density porous body with a closed-cell structure using the extrusion foam molding method.

更に一方、上述の過酷な使用条件下での多孔質体の断熱
性能の向上化には、必ずしも多孔質体の低密度化が，良
策とは思えない。Furthermore, on the other hand, lowering the density of the porous body does not necessarily seem to be a good idea for improving the heat insulation performance of the porous body under the above-mentioned severe usage conditions.

その理由は、定体積内の固体成分が少なくなれば耐水性
が低下するのは当然のことと予測されるからである。The reason for this is that it is expected that as the solid component within a given volume decreases, the water resistance will naturally decrease.

本発明者等は、このような現状に鑑み上述の如き、押出
発泡或形の現状技術で生じる現象を、多孔質体の厚み断
面方向に取入れてこれを組合せば、現状技術そのままで
は得ることのできない別の性質を持つ多泡質体が得られ
るとする仮説の下に研究を重ねた結果ようやく本発明を
完成したものである。In view of the current situation, the inventors of the present invention have proposed that by incorporating the phenomena that occur in the current technology of extrusion foaming as described above in the thickness cross-sectional direction of the porous body and combining them, it will be possible to obtain a phenomenon that cannot be obtained with the current technology as it is. The present invention was finally completed as a result of repeated research based on the hypothesis that a porous material with different properties could be obtained.

本発明の目的は、多孔質体全体としての断熱性能並に耐
水性（吸水による経時断熱性能の持続性）に優れ且つ、
圧縮強度、曲げ強度等の機械特性及び切断、切削加工性
には何等遜色のない押出発泡或形による一体物の多孔質
体を提供することにある。The purpose of the present invention is to have excellent heat insulation performance and water resistance (sustainability of heat insulation performance over time due to water absorption) as a whole of the porous body, and
The object of the present invention is to provide a one-piece porous body made of extruded foam that has comparable mechanical properties such as compressive strength and bending strength, and cutting and cutting workability.

以下本発明の内容を、重要な要件にそって詳述する。The content of the present invention will be explained in detail below along with important requirements.

本発明の重要な要件は、 ■ 実際に使用される製品の厚さにほぼ一致する厚みで
製造される合威樹脂平板状多孔質体を、厚み断面の上・
下層部と中央層部とで密度及び気泡径の双方が異なる三
層様分布をもった一体の独立気泡に富む多孔質体とする
。The important requirements of the present invention are: (1) The flat plate-shaped porous body of Hewei resin, which is manufactured with a thickness that almost matches the thickness of the product actually used, is
A porous body rich in closed cells has a three-layer-like distribution in which both the density and the cell diameter are different between the lower layer and the middle layer.

■ 該上・下層部は、密度ｄｓ（表面から約３間の部分
で示す代表値）が４ ０ 〜１ ０ ０ｋｇ／ ｍ’、
平均気泡径Ｉｓ（厚み方向の測定値）が０．０２〜０．
４朋の各範囲とし該中央層部は、密度ｄｃ（中央部約３
ｙｒｔｔｎの部分で示す代表値）が２５〜５ ０ ｋｇ
／ ｍ、平均気泡径１ｃ（厚み方向の測定値）が０．１
〜０．６ｍｍの各範囲とする。■ The upper and lower layers have a density ds (typical value shown in the area between about 3 mm from the surface) of 40 to 100 kg/m',
The average cell diameter Is (measured value in the thickness direction) is 0.02 to 0.
Each area has a density dc (about 3
Typical value shown in yrttn part) is 25 to 50 kg
/ m, average bubble diameter 1c (measured value in the thickness direction) is 0.1
Each range is 0.6 mm.

以上のＣ■の組合せの合成樹脂多孔質体である。This is a synthetic resin porous body having a combination of the above C■.

その必要理由として、先ず■は、現状の押出発泡成形技
術上の制約及び得られる多孔質体の特性的制約とを三層
様分布をもつ一体の多孔質体として組合せることで打関
し、現状技術では得られなかった異種の多孔質体を創作
しようとする本発明の基本的技術思想を示すものである
。The reasons why this is necessary are as follows: First, the current extrusion foam molding technology constraints and the characteristic constraints of the obtained porous body can be combined into an integrated porous body with a three-layer distribution. This shows the basic technical idea of the present invention, which aims to create a different type of porous body that could not be obtained by technology.

次に■の理由は、現状の押出発泡技術で得られる多孔質
体の調整が可能で、且つ本発明の目的に合う密度と気泡
径の範囲の選択である。Next, the reason for (2) is that the porous body obtained by the current extrusion foaming technology can be adjusted, and the range of density and cell diameter can be selected to meet the purpose of the present invention.

即ち例えば、密度ｄｓが４ ０ｋｇ／ ｍ’未満では耐
水性が悪化するし逆に１００ｋｇ／ｍ”を越えるもので
は、多孔質体全体としての密度が高まり断熱性能が低下
することにつながるからである。That is, for example, if the density ds is less than 40 kg/m', water resistance deteriorates, whereas if it exceeds 100 kg/m', the density of the porous body as a whole increases, leading to a decrease in heat insulation performance. .

平均気泡径１ｓは上記密度の範囲にあって、０．０２ｍ
ｍ未満では破泡連通化が目立ち、断熱性能・耐水性が低
下するし０．４間を超える気泡径では、断熱性能が低下
するし、中央部層多孔質体の、機械的特性を補う役割を
失うからである。The average bubble diameter 1s is within the above density range and is 0.02m.
If the diameter of the bubbles is less than 0.4 m, the bubbles will become conspicuous and the insulation performance and water resistance will deteriorate. If the diameter of the cells exceeds 0.4 m, the insulation performance will decrease. This is because you will lose.

中央部層の密度ｄｃ，気泡径ＩＣは、主に多孔質体本来
の断熱性能と機械的特性を保持・調整するもので、例え
ば、密度ｄｃが２ ５ ｋｇ／ ｍ’未満では、気泡径
が０．６山のものでも気泡の連通化が進み、断熱性能及
び機械特性が悪化するし、逆に気泡径が０．１間のもの
でも密度ｄｃが５ ０ ｋｇ／ｍ３を超えて大きいもの
では、断熱性能が得られない上に切断・切削加工性が悪
化するのである。The density dc and the cell diameter IC of the central layer are mainly used to maintain and adjust the insulation performance and mechanical properties inherent to the porous material. For example, when the density dc is less than 25 kg/m', the cell diameter is Even if the diameter of the bubbles is between 0.6 and 0.6, the air bubbles will become interconnected and the insulation performance and mechanical properties will deteriorate.On the other hand, even if the diameter of the bubbles is between 0.1 and the density dc is larger than 50 kg/m3, In addition to not being able to obtain thermal insulation performance, cutting and machinability deteriorate.

次いで■の必要理由は、中央部層に対し、両表層部には
、気泡径の小さい且つ密度の大きい多孔質層を分布させ
る必要性及び、その分布を得る気泡径・密度の組合せの
限度を示す指標を示すものである。Next, the reason for (①) is the need to distribute porous layers with small bubble diameter and high density in both surface layers with respect to the central layer, and the limit of the combination of bubble diameter and density to achieve this distribution. This indicates the index to be displayed.

ｄｓ Ｉｓ 即ちー，一が各々１．２，０．１の値より小さいｄｃ
ｌｃ ときは、中央部層多孔質体の特質、例えば、機械特性及
び又は切断・切削加工性を悪化させないでｄｓ 耐水性を高めることは期待できないし、逆に−，ｄｃ １Ｓ 一が各々２，０．８の値を超えて大きいときは、１Ｃ 断熱性能、及び又は機械特性を悪化させないで耐水性を
高めることが出来ないことを意味している。ds Is i.e. -, dc is less than the value of 1.2, 0.1 respectively
When lc, it is impossible to expect to improve the water resistance of the central layer porous material, such as mechanical properties and/or cutting/machining properties, and conversely, -, dc 1S is 2, When the value exceeds 0.8, it means that water resistance cannot be improved without deteriorating 1C heat insulation performance and/or mechanical properties.

本発明は上記■わ■を組合せたことで、現状の押出発泡
成形技術水準そのままでは得ることのできなかった断熱
性能、耐水性に優れた多孔質体を機械特性、切削・切断
加工性の損なわれない状態のものとして、具現させるこ
とに成功したものである。The present invention combines the above points (W) and (W) to create a porous body with excellent heat insulation performance and water resistance, which could not be obtained using the current extrusion foam molding technology. This is something that we succeeded in bringing to life as something that could not be imagined.

本発明でいう厚さ方向の気泡径の意味は、多孔質体の断
熱性能は熱が流れる方向の気泡径に関係するという知見
から多孔質の厚さ方向の気泡寸法に着目して測定表現し
たという意味である。The meaning of the bubble diameter in the thickness direction in the present invention is expressed by focusing on the bubble size in the thickness direction of the porous material based on the knowledge that the insulation performance of a porous material is related to the bubble diameter in the direction of heat flow. That is what it means.

即ち具体的には上下層部、中央部の各々の厚み３關の代
表部分について断面巾方向に略等間隔に厚み方向へ５本
の直線を引き直線にかかる気泡の厚み方向の直径寸法を
計る操作を別の５個所の断面で繰返し、その値の平均値
で示す。Specifically, five straight lines are drawn in the thickness direction at approximately equal intervals in the cross-sectional width direction for each of the three representative thicknesses of the upper, lower, and central layers, and the diameter of the bubbles in the thickness direction is measured. The operation was repeated at five other cross sections, and the average value is shown.

尚この場合の測定には倍率の明確な拡大装置（１０〜５
０倍）を用いた方が精度が高い。In this case, a magnifying device with a clear magnification (10 to 5
0x) is more accurate.

本発明でいう密度とは多孔質体のかさ密度の意味で、気
泡径の場合と同様に上下層部、中央部の各々の厚み３間
の代表部分から巾約５０ｍｍ、長さ約５０ｍｍのサンプ
ルを片寄ない５個所から切出し体積と重量との比を求め
その各平均値で示す。In the present invention, the term "density" refers to the bulk density of the porous material, and as in the case of the bubble diameter, a sample with a width of about 50 mm and a length of about 50 mm is taken from the representative part between the thicknesses of 3 in the upper and lower layer parts and the central part. Cut out the material from 5 locations that are not lopsided, calculate the ratio of volume to weight, and show the average value of each.

本発明でいう合或樹脂とはポリエチレン、ポリスチレン
、ポリ塩化ビニル等で代表される押出発泡戒形が可能な
樹脂を総称するが、内でも硬質発泡体が得られるポリス
チレン系樹脂を選ぶ方が有利である。The synthetic resin used in the present invention is a general term for resins that can be extruded and foamed, such as polyethylene, polystyrene, polyvinyl chloride, etc., but it is more advantageous to choose polystyrene-based resins that can form rigid foams. It is.

本発明でいう切断・切削加工性とは、多孔質体を切断し
たり相決り加工、やといざね加工等の切削加工を行なう
とき、加工端面が欠けたり割れたり、或はささくれが生
じたりすることなく、平滑な加工面として形或されるこ
とをいう。In the present invention, the term "cutting/cutting workability" refers to the possibility that when cutting a porous body, or performing machining such as interlocking machining or chiseling machining, the processed end surface may be chipped, cracked, or have hangnails. It means that it is formed into a smooth machined surface without cutting.

本発明の多孔質体の製法は、現状押出発泡或形技術を、
巧に組合せることによって完成される。The method for manufacturing the porous body of the present invention uses the current extrusion foaming or shaping technology.
Perfected by skillful combinations.

即ち先ずその製法原理について知見・考察をふまえて記
述すると、製法に供する樹脂組戒物には多数の気泡核を
形成する要素と生成した気泡を均質に成長させ、ひずみ
のない薄肉の気泡膜を形成させ得る可塑伸長性に富ませ
る要素及び、金属壁等との摩擦抵抗を小さくして、樹脂
の流動或は滑性を高める要素とが同時に要求される。First, the principle of the manufacturing method will be described based on knowledge and considerations.The resin composition used in the manufacturing method is made by allowing the elements that form a large number of bubble nuclei and the generated bubbles to grow homogeneously to form a thin, strain-free cell film. There is a need for an element that can be formed to enhance plastic extensibility, and an element that reduces frictional resistance with metal walls and the like and enhances the flow or slipperiness of the resin.

その理由は、独立気泡構造の小径気泡多孔質体の形或を
容易にすることの他に後述する様な気泡数の分布及びそ
の成長を局部的（こ変更する手段並に生或成長した気泡
の固化固定を調節する手段の各々の作用を円滑に行なわ
ざるためのものである。The reason for this is that in addition to facilitating the formation of a small-diameter porous body with a closed cell structure, the distribution of the number of bubbles and the growth thereof can be locally changed (as will be described later), as well as the means to locally change the distribution of the number of bubbles and the generation or growth of the bubbles. This is to ensure that the respective functions of the means for adjusting the solidification and fixation of the material are performed smoothly.

次に押出された一体の押出物の厚み方向に、気泡数、気
泡径、密度等の異なる分布を形或させる手段について述
べると、究極のところは押出前乃至押出直後の、流動可
能状態にある樹脂流の中央部と表層部との間に、大きさ
の違う物理的刺激を与えることである。Next, we will discuss the means of forming different distributions of cell number, cell diameter, density, etc. in the thickness direction of the extruded integral extrudate.The ultimate solution is to form a flowable state before or immediately after extrusion. This involves applying physical stimuli of different sizes between the center and surface of the resin flow.

この必要性は、同じ組成の樹脂の中に生じる気泡核数の
分布状態を好ましい状態に調節するためのもので、例え
ば樹脂流の中央部と表層部との間に剪断応力差、分子振
動エネルギー差、伸長応力差等の刺激の差を生ぜしめ、
そこに生れる造核現象の違いを利用するのである。This necessity is to adjust the distribution state of the number of bubble nuclei generated in resins of the same composition to a favorable state. It causes a difference in stimulation such as a difference in stress, a difference in elongation stress, etc.
The difference in the nucleation phenomenon that occurs there is utilized.

そして次には、押出後発泡の或長が進行している樹脂層
の中央部と表層部との間で、温度勾配を与えながら冷却
固化を完了させる。Next, cooling and solidification are completed while applying a temperature gradient between the center portion and the surface layer portion of the resin layer where foaming after extrusion is progressing for a certain period of time.

このことは多孔質体に生じた気泡数分布と気泡径の分布
とを好みの状態に調整するもので、多孔質体の密度分布
を与えることにもつながる最終仕上の段階に当る。This adjusts the bubble number distribution and bubble diameter distribution generated in the porous body to the desired state, and corresponds to the final finishing stage that also leads to giving the porous body a density distribution.

本発明の実施例では、基材樹脂にポリスチレン樹脂を用
いた場合を例示したので、上述の製造方法の具体的内容
は次の手段・条件を採用することで完成されている。In the examples of the present invention, the case where polystyrene resin was used as the base resin was exemplified, so the specific content of the above-mentioned manufacturing method was completed by adopting the following means and conditions.

２ 溶融 押出製造 公知の７５間φ押出製造、即ち加圧・加熱下で溶融中の
樹脂に発泡剤を加圧注入して含有させて混合し、発泡適
性温度に調温しで押出発泡させる通常の押出装置を使用
。2. Melting Extrusion Manufacturing Known 75-diameter extrusion manufacturing, that is, a blowing agent is injected under pressure into the melting resin under pressure and heat, the mixture is mixed, and the temperature is adjusted to the appropriate temperature for foaming, followed by extrusion foaming. using extrusion equipment.

尚、造核調節装置には次の手段を用いた。The following means was used for the nucleation control device.

上記押出装置のダイ相当部上下に、超音波発生装置〔精
電舎電子工業（株）社製、ＳＯＮＯＰＥＴ−ＩＯＯＯＢ
（出力ＩＫＷ））の２台の各々から電気的に接続された
振動伝達部（固定ホーン）を固定し、その先に設けた振
動ホーン部がダイス開ロオリフイスの上面、下面部にな
るように設計されている。An ultrasonic generator (manufactured by Seidensha Electronics Co., Ltd., SONOPET-IOOOB) is installed above and below the die-corresponding part of the extrusion device.
(output IKW)) is designed so that the vibration transmitting parts (fixed horns) electrically connected to each of the two units are fixed, and the vibration horn parts provided at the end become the upper and lower parts of the die opening rotorifice. has been done.

この振動ホーン部は開ロオリフイス両側部を構成する固
定部材と嵌合溝で上下振動可能に側部固定され、高さ１
１ｎｖＩＬ１横巾３００ｍｍの開口面積のオリフィスが
形成されている。This vibrating horn part is fixed on the sides so that it can vibrate up and down using the fixing members and fitting grooves that make up both sides of the opening lower orifice, and has a height of 1
1nvIL1 An orifice with an opening area of 300 mm in width is formed.

４ 多孔質冷却装置及び条件 ダイ面近傍から押出方向の５７７１の長さに亘り多孔質
体に約１ｓＯｇ／ｆｆｌの接面挾圧を与えると共に多孔
質体を最終５０℃以下に冷却する過程で多孔質体の中央
部と表面部との間に与える２５〜４０℃の範囲の温度差
を、押出直後〜約３ｍ長さの部分で設定できるようにし
た上下一対の金属板接面冷却装置で、約１ｍ長単位の金
属製中空ブロックが各々断熱材を介して５個千列に接続
されていて、各々の中空部に冷却水が独立して流通出来
るように構成された装置である。4 Porous cooling device and conditions A contact pressure of about 1 sOg/ffl is applied to the porous body over a length of 5771 in the extrusion direction from the vicinity of the die surface, and the porous body is cooled to a final temperature of 50°C or less. A pair of upper and lower metal plate contact surface cooling devices that can set the temperature difference in the range of 25 to 40 °C between the center and surface of the mass from immediately after extrusion to approximately 3 m long. The device is constructed in such a way that five metal hollow blocks each measuring approximately 1 meter in length are connected in 1,000 rows through heat insulating materials, and cooling water can flow through each hollow section independently.

第１表は、上記具体的装置条件を用いて各種の組合せ実
験を行なって得た６種類の板状多孔質体について、評価
した結果を実施例１〜６として一覧表にしたものである
。Table 1 lists, as Examples 1 to 6, the evaluation results of six types of plate-shaped porous bodies obtained by conducting various combination experiments using the above-mentioned specific equipment conditions.

上記製法で得た多孔質板は、その上下表面に接面冷却で
生じる薄膜を有しているので、実施例１，３，４．６の
ものはこれを除去し、実施例２，５ではこれを残したも
ので示す。The porous plate obtained by the above manufacturing method has thin films on its upper and lower surfaces that are generated by cooling the contact surfaces, so this was removed in Examples 1, 3, and 4.6, and in Examples 2 and 5. This is shown by what remains.

比較のために、通常の押出発泡成形法で得た４種（比較
例１，２，３．４）について、本発明品と同じ評価を行
ない参考に供するようにした。For comparison, four types (Comparative Examples 1, 2, and 3.4) obtained by a conventional extrusion foam molding method were subjected to the same evaluation as the products of the present invention and used for reference.

第１表中の、上下層部、中央部の密度（ｄｓ，ｄｃ）及
び平均気泡径（ Ｉｓ ，ｌｃ）は本文記載の方ｄｓ
Ｉｓ 法で測定した値でー，−は各々計算値を示す。In Table 1, the density (ds, dc) and average bubble diameter (Is, lc) of the upper and lower layer parts and the center part are as described in the text ds
The values were measured using the Is method, and - and - indicate calculated values.

ｄｃ Ｔｃ 第１表中の耐水性及ひ断熱性能の評価は下記による。dc Tc The evaluation of water resistance and heat insulation performance in Table 1 is as follows.

耐水性評価法（促進吸水試験） 板状多孔質体を巾１００ｍｍ，長さ１００ｍｍ（厚み２
５山）の大きさに５本切出し、各々の乾燥重量を測定し
た後、目標７０℃に温調した水槽内に水面下約５０朋に
水没するように各々の多孔質体を金網で固定し、その条
件を１００日間に亘って維持した後取出した。Water resistance evaluation method (accelerated water absorption test)
After cutting out 5 pieces of the same size (5 mounds) and measuring their dry weight, each porous body was fixed with a wire mesh so that it was submerged approximately 50 mm below the surface of the water in a water tank whose temperature was controlled to a target of 70°C. The conditions were maintained for 100 days and then removed.

取出した各多孔質体は無水アルコール内に５秒間浸漬し
た後、５０℃の温風下で５分間放置して表面部の付着水
分を除去し、多孔質体重量を測定して下式でその吸水率
（体積パーセント〕−を言４．して５個の平均値で示す
。Each porous body taken out was immersed in absolute alcohol for 5 seconds, and then left for 5 minutes under warm air at 50°C to remove moisture adhering to the surface.The weight of the porous body was measured and its water absorption was calculated using the following formula. The ratio (volume percent) is expressed as the average value of 5 values.

尚本評価法の吸水率は、本文記載の「過酷な条件下使用
時」の代用特性で、吸水率が１％を越えて大きいものと
、１％未満のより小さいものとは実用上の経時断熱性能
の持続性に大差が生じることが、実験的に確かめられて
いるので、この値をもって「耐水性」とした。The water absorption rate in this evaluation method is a substitute characteristic for "when used under harsh conditions" as stated in the text, and those with a water absorption rate greater than 1% and those with a smaller water absorption rate less than 1% are based on actual aging. It has been experimentally confirmed that there is a large difference in the sustainability of insulation performance, so this value is defined as "water resistance."

断熱性能（熱伝導率） 製造１日後の多孔質体を巾２ ５ ０關、，長さ２５０
順（厚さ２５ｍｍ）の大きさに切出し、２４℃目標に調
温した恒温室で１日静置後、ＡＳＴＭＣ５１８平板比較
法に準じ測定した値で、Ｏ℃での値に換算して示した。Insulation performance (thermal conductivity) The porous body after 1 day of manufacture has a width of 250 mm, and a length of 250 mm.
The values were measured according to the ASTMC518 flat plate comparison method after being cut into pieces (thickness 25 mm) and left for one day in a constant temperature room controlled to a target temperature of 24 degrees Celsius.The values are converted to values at 0 degrees Celsius. .

この値は、より小さい値の方が断熱性能に優れることを
意味する。This value means that the smaller the value, the better the heat insulation performance.

水蒸気透過量 ＡＳＴＭＥ ９６に準拠、即ち、厚み２５朋の多孔質
体を介してその両側が２３℃で相対温度差が５０％とな
る条件下で生じる水蒸気透過量（ｇ／ｍ“ｈ）で示す。Water vapor permeation amount Based on ASTM E 96, that is, it is expressed as the amount of water vapor permeation (g/m"h) that occurs through a porous body with a thickness of 25 mm under the condition that the relative temperature difference is 50% at 23 ° C on both sides. .

第１表の結果によると、本発明の多孔質体の耐水性は、
体積吸水率で０．５％以下の値を示し、比較品の１５〜
２．４％の値の耐水性に対し、有意性をもって改善され
ていると云える。According to the results in Table 1, the water resistance of the porous body of the present invention is as follows:
It shows a value of 0.5% or less in terms of volumetric water absorption, and the comparison product has a value of 15~
It can be said that the water resistance is significantly improved compared to the water resistance value of 2.4%.

この現象効果の傾向は、水蒸気透過量の関係傾向ともほ
ぼ一致し、水蒸気の移動に伴なう多孔質体への水分蓄積
量の低減にもつながる。The tendency of this phenomenon effect almost coincides with the relational tendency of the amount of water vapor permeation, and also leads to a reduction in the amount of water accumulated in the porous body due to the movement of water vapor.

本発明の上記耐水性の向上化は、多孔質体の密度を高め
たり多孔質表面の薄膜にたよったりしたものではないの
で、断熱性能を高められた水準に於で完成されていると
ころに本発明の特長があると云える。The above-mentioned improvement in water resistance of the present invention is not achieved by increasing the density of the porous body or by relying on a thin film on the porous surface. It can be said that there are features of the invention.

又本発明の第１表の多孔質体の各々についてＡＳＴＭＤ
−１６２１に示される「圧縮強度」及びＡＳＴＭＣ２０
３−５８に示される「曲げ強度」について評価したと
ころ、各々２．７〜３ｋｇ／ｃＩＩＬ及び５〜８ｋｇ／
ｃｙｙｔの値を示し、比較品に比べて優れた値を示しこ
そすれ、何等遜色は見出せなかった。Also, for each of the porous bodies in Table 1 of the present invention, ASTMD
- “Compressive strength” shown in 1621 and ASTM C20
When the "bending strength" shown in 3-58 was evaluated, it was 2.7 to 3 kg/cIIL and 5 to 8 kg/cIIL, respectively.
cyyt value, and showed an excellent value compared to the comparative product, and could not find any inferiority.

又、多孔質の端面にやとい実切削加工を施こす実験も行
なったが、比較品に比べて何等遜色はなく、優れた仕上
精度を示した。We also conducted an experiment in which the end face of the porous material was subjected to groin cutting, and the results showed no inferiority compared to comparative products, showing excellent finishing accuracy.

上記構或を満す本発明の多孔質体は、防水のない屋上断
熱・地下蓄熱槽断熱用等の改良された断熱材として、広
くその用途の拡大が期待できる。The porous body of the present invention that satisfies the above structure can be expected to have a wide range of applications as an improved heat insulating material for non-waterproof rooftop insulation, underground heat storage tank insulation, and the like.

Claims (1)

【特許請求の範囲】 １ 連続押出し発泡或形方法によって実際に使用される
製品の厚さにほぼ一致する厚みで一体に製造される独立
気泡に富む合成樹脂平板状多孔質体において、厚さ方向
の上下表面から約３間の部分の密度ｄｓが４０〜１００
ｋｇ／ｍ、この部分の厚さ方向の平均気泡径ＩＳが０．
０ ２〜０。 ４關、厚さ方向の中央部約３朋の部分の密度ｄｃが２
５ 〜５ ０ ｋｙ／ ｍ、この部分の厚さ方向の平均
気泡径１ｃが０．１〜０．６ｍｍの範囲にあり、かつ、
ｄｓ ， ｄｃ ， Ｉｓ ， ｌｃの間にｄｓ
Ｉｓ １．２＜−＜；：２および０． １ ＜−＜： ０．
８なる関係− ｄ ｃ − −１
ｃ−を満す３層様分布であることを特徴とする合戒樹脂
多孔質体。[Scope of Claims] 1. In a synthetic resin plate-like porous body rich in closed cells manufactured in one piece by a continuous extrusion foaming or shaping method to a thickness that almost matches the thickness of a product actually used, the thickness direction The density ds of the part between about 3 from the upper and lower surfaces of is 40 to 100
kg/m, and the average bubble diameter IS in the thickness direction of this part is 0.
0 2~0. 4. The density dc of the central part about 3 mm in the thickness direction is 2.
5 to 50 ky/m, the average bubble diameter 1c in the thickness direction of this part is in the range of 0.1 to 0.6 mm, and
ds between ds, dc, Is, lc
Is 1.2<-<;: 2 and 0. 1 <-<: 0.
8 relationship - d c - -1
A porous resin material having a three-layer distribution satisfying c-.