【発明の詳細な説明】[Detailed description of the invention]
本発明は、熱硬化性樹脂成形品の製造法に係
り、断熱材料などとしての性能を向上させるため
の改良に関する。
断熱材料として従来から用いられている熱硬化
性樹脂成形品には次のようなものがある。例え
ば、綿布、紙等のセルロース基材をフエノール樹
脂、エポキシ樹脂等の本来断熱性、耐熱耐久性の
よい熱硬化性樹脂で結合硬化せしめたものがあ
り、これは80〜120℃の耐熱耐久性能と７×
10-4Cal／cm・sec・℃程度の熱伝導率を有する。
また、ガラス、アスベスト等の無機質基材を上記
と同様の熱硬化性樹脂で結合硬化せしめたもの
は、130〜200℃の耐熱耐久性と10×10-4〜11×
10-4Cal／cm・sec℃の熱伝導率を有する。これら
の熱硬化性樹脂成形品は、いずれもフエルト類、
樹脂発泡体、熱可塑性樹脂成形品等では得られな
い耐熱性、耐圧縮強度を有し、また、金属類とは
比較にならない高い断熱性を有するものである。
しかし、上記の熱硬化性樹脂成形品について
も、例えば自動車用ヒートインシユレータとし
て、あるいは電気器具の高温部分で電気絶縁材料
として使用する場合など130〜200℃の高温度領域
において優れた断熱性と耐熱耐久性と機械的強度
を同時に保持せんとすることは次に示す如く充分
でなかつた。
(1) 断熱性の良いセルローズ基材を使用した熱硬
化性樹脂成形品は高い断熱性を示すが、セルロ
ーズ基材の耐熱性が良いために100〜120℃以上
の高温では耐熱耐久性が不足する。
(2) 高い耐熱耐久性をもつ無機質繊維基材を使用
した熱硬化性樹脂成形品は130〜200℃の高温領
域においても耐熱耐久性は優れるが、無機質繊
維基材は熱伝導率が少し高いので断熱性は若干
劣る。
(3) 上記(2)において断熱性を改良するために、無
機質繊維基材を結合硬化せしめる熱硬化性樹脂
の含有量を増加すると断熱性は向上するが成形
品は脆くなつたり機械的強度は低下する。
本発明の目的は、上述のようなそれぞれの場合
における欠点を除去し、130〜200℃の高温領域に
おいても断熱性能、耐熱耐久性能、機械的強度お
よび電近的性能の優れた熱硬化性樹脂成形品を提
供することである。
上記目的を達成するために、本発明は、耐熱性
に優れる完全硬化したフエノール樹脂粉末を活用
し、このフエノール樹脂粉末と無機質繊維を配合
して混練したＢステージのフエノール樹脂成形材
料を所定形状に加熱加圧成形するものである。耐
熱性に優れる完全硬化したフエノール樹脂の粉末
と無機質繊維補強基材をフエノール樹脂で結合成
硬化せしめた熱硬化性樹脂成形品は、耐熱耐久
性、断熱性に優れ、また脆くなつたり高い温度で
使用しても熱応力割れを生じることはない。
実施例
重量比で耐熱性フエノール樹脂30％と基材とし
て完全硬化したフエノール樹脂の粉末30％とガラ
ス繊維40％を混練してＢステージ（常態では硬化
しているが熱あるいは溶剤で可塑化する状態、以
下同様）の成形材料を得た。この成形材料を所定
の形状に加熱加圧成形して成形品とした（以下発
明品という）。次に、従来の熱硬化性樹脂成形品
の例について説明する。
従来例 １
実施例と同様のフエノール樹脂30％とガラス繊
維70％を混練してＢステージの成形材料を得た。
この成形材料を所定の形状に加熱加圧成形して成
形品とした（以下従来品１という）。
従来例 ２
実施例と同様のフエノール樹脂55％と紙45％と
を混練してＢステージの成形材料を得た。この成
形材料を所定の形状に加熱加圧成形して成形品と
した（以下従来品２という）。
第１表に発明品及び従来品１，２の機械的強
度、断熱性、耐熱性についての試験結果を示す。
The present invention relates to a method of manufacturing a thermosetting resin molded article, and relates to an improvement for improving the performance as a heat insulating material. Thermosetting resin molded products conventionally used as heat insulating materials include the following. For example, there are products in which cellulose base materials such as cotton cloth and paper are bonded and cured with thermosetting resins such as phenolic resins and epoxy resins, which inherently have good heat insulation and heat resistance durability. and 7×
It has a thermal conductivity of about 10 -4 Cal/cm・sec・℃.
In addition, inorganic base materials such as glass and asbestos bonded and cured with the same thermosetting resin as above have heat resistance durability of 130 to 200°C and 10 × 10 -4 to 11 ×
It has a thermal conductivity of 10 -4 Cal/cm・sec°C. These thermosetting resin molded products are all made of felt,
It has heat resistance and compressive strength that cannot be obtained with resin foams, thermoplastic resin molded products, etc., and also has high heat insulation properties that are incomparable to metals. However, the above-mentioned thermosetting resin molded products also have excellent heat insulation properties in the high temperature range of 130 to 200 degrees Celsius, such as when used as heat insulators for automobiles or as electrical insulation materials in high-temperature parts of electrical appliances. It was not sufficient to simultaneously maintain heat resistance, durability, and mechanical strength as shown below. (1) Thermosetting resin molded products using a cellulose base material with good heat insulation properties show high heat insulation properties, but because the cellulose base material has good heat resistance, it lacks heat resistance and durability at high temperatures of 100 to 120 degrees Celsius or higher. do. (2) Thermosetting resin molded products using inorganic fiber base materials with high heat resistance and durability have excellent heat resistance and durability even in the high temperature range of 130 to 200℃, but inorganic fiber base materials have slightly high thermal conductivity. Therefore, the insulation properties are slightly inferior. (3) In order to improve the heat insulation properties in (2) above, increasing the content of the thermosetting resin that binds and hardens the inorganic fiber base material improves the heat insulation properties, but the molded product becomes brittle and its mechanical strength decreases. descend. The purpose of the present invention is to eliminate the drawbacks in each case as described above, and to create a thermosetting resin that has excellent heat insulation performance, heat resistance durability performance, mechanical strength, and electrical performance even in the high temperature range of 130 to 200°C. The purpose is to provide molded products. In order to achieve the above object, the present invention utilizes completely cured phenolic resin powder with excellent heat resistance, and forms a B-stage phenolic resin molding material into a predetermined shape by blending and kneading this phenolic resin powder with inorganic fibers. It is molded by heating and pressure. Thermosetting resin molded products, which are made by bonding and curing completely cured phenolic resin powder with excellent heat resistance and an inorganic fiber reinforced base material with phenolic resin, have excellent heat resistance, durability, and insulation properties, and do not become brittle at high temperatures. No thermal stress cracking will occur during use. Example By weight, 30% heat-resistant phenolic resin, 30% completely cured phenolic resin powder as a base material, and 40% glass fiber are kneaded to form a B-stage (hardened under normal conditions, but plasticized with heat or solvent). A molding material was obtained in the same condition as above). This molding material was molded under heat and pressure into a predetermined shape to produce a molded product (hereinafter referred to as the invention product). Next, an example of a conventional thermosetting resin molded product will be explained. Conventional Example 1 A B-stage molding material was obtained by kneading 30% phenolic resin and 70% glass fiber as in Example.
This molding material was molded under heat and pressure into a predetermined shape to form a molded product (hereinafter referred to as conventional product 1). Conventional Example 2 A B-stage molding material was obtained by kneading 55% phenolic resin and 45% paper as in Example. This molding material was molded under heat and pressure into a predetermined shape to form a molded product (hereinafter referred to as conventional product 2). Table 1 shows the test results for the mechanical strength, heat insulation, and heat resistance of the invented product and conventional products 1 and 2.
【表】
耐熱性試験はUL規格の試験方法に準じた。
第１表から明らかなように、本発明品は機械的
強度、断熱性、耐熱性のいずれも優れている。熱
伝導率７×10-4Cal／cm・sec℃と11×10- 4Cal／
cm・sec℃との差は、200℃の熱源に10mm厚の試験
片を接触せしめたときの試験片の反対側の表面温
度130℃と160℃になる程度の大きな耐熱効果の差
につながるものである。
本発明の効果をまとめると次のとおりである。
(1) 完全硬化したフエノール樹脂の粉末は、成形
品本体を形成するフエノール樹脂と同様４×
10-4Cal／cm・sec℃程度の低い熱伝導率を有し
耐熱性もあるので、これを用いた熱硬化性樹脂
成形品は断熱性に優れ、無機質繊維の配合と相
まつて130％〜200℃の高温領域において耐熱耐
久性も優れる。
(2) 基材としてガラス繊維などの無機質繊維を混
合した場合に熱硬化性樹脂の含有率を増して断
熱性を上げても脆くなつたり熱応力割れを生じ
たりすることがなく、十分な機械的強度を保持
している。
(3) 完全硬化したフエノール樹脂の粉末を使用し
ているので高温領域においても電気絶縁性に優
れ断熱材としての用途だけでなく電気器具の絶
縁部材としても優れる。[Table] The heat resistance test was conducted in accordance with the UL standard test method. As is clear from Table 1, the products of the present invention are excellent in mechanical strength, heat insulation, and heat resistance. Thermal conductivity 7×10 -4 Cal/cm・sec℃ and 11× 10 -4 Cal/
The difference between cm・sec℃ leads to a large difference in heat resistance effect, such as when a 10mm thick test piece is brought into contact with a 200℃ heat source, the surface temperature on the opposite side of the test piece is 130℃ and 160℃. It is. The effects of the present invention are summarized as follows. (1) The completely cured phenolic resin powder is 4×
It has a low thermal conductivity of about 10 -4 Cal/cm・sec°C and is also heat resistant, so thermosetting resin molded products using this material have excellent heat insulation properties, and together with the inorganic fiber composition, it has a thermal conductivity of 130% ~ It also has excellent heat resistance and durability in the high temperature range of 200℃. (2) When inorganic fibers such as glass fibers are mixed as a base material, even if the content of thermosetting resin is increased to improve insulation properties, it will not become brittle or cause thermal stress cracking, and will have sufficient mechanical strength. It maintains its objective strength. (3) Since it uses completely cured phenolic resin powder, it has excellent electrical insulation properties even in high-temperature areas, making it excellent not only for use as a heat insulator but also as an insulating member for electrical appliances.