JPS6020110B2 - Manufacturing method of self-hardening mold binder - Google Patents
Manufacturing method of self-hardening mold binderInfo
- Publication number
- JPS6020110B2 JPS6020110B2 JP1976681A JP1976681A JPS6020110B2 JP S6020110 B2 JPS6020110 B2 JP S6020110B2 JP 1976681 A JP1976681 A JP 1976681A JP 1976681 A JP1976681 A JP 1976681A JP S6020110 B2 JPS6020110 B2 JP S6020110B2
- Authority
- JP
- Japan
- Prior art keywords
- furfuryl alcohol
- industrial
- boiling point
- manufacturing
- urea
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
- B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
- B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
- B22C1/22—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins
- B22C1/2233—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- B22C1/224—Furan polymers
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Mold Materials And Core Materials (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Description
【発明の詳細な説明】
本発明は目硬性鋳型用粘結剤の製造法に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a binder for hard molds.
目硬性鋳型用粘結剤としてはフルフリルアルコール・尿
素ホルムアルデヒド共縮合樹脂、フルフリルアルコール
・フェノールホルムアルデヒド共縮合樹脂等があるがこ
れらフルフリルアルコールを使用する樹脂は鋳型製造時
に刺激臭を発し作業環境の悪化をもたらしている。本発
明はこの欠点を改良した目硬性鋳型用粘結剤の製造法を
提供するものである。通常、目硬性鋳型用粘結剤のフル
フリルアルコール・尿素・ホルムアルデヒド共縮合樹脂
の製造法にはフルフリルアルコール、尿素およびホルム
アルデヒドを共縮合させた後脱水工程を行なう方法、お
よび脱水後更にフルフリルアルコールを添加し共縮合を
行なう方法がある。Binding agents for hard molds include furfuryl alcohol/urea formaldehyde co-condensed resins, furfuryl alcohol/phenol formaldehyde co-condensed resins, etc. However, resins that use furfuryl alcohol emit a pungent odor during mold manufacturing and are harmful to the work environment. This has led to the deterioration of The present invention provides a method for producing a binder for hard molds that improves this drawback. Normally, the method for producing furfuryl alcohol/urea/formaldehyde co-condensed resin, which is a binder for hard molds, involves co-condensing furfuryl alcohol, urea and formaldehyde, followed by a dehydration process, and then further furfuryl alcohol after dehydration. There is a method of co-condensing by adding alcohol.
またフルフリルアルコール・ホルムアルデヒド・フェノ
ール共縮合樹脂においてはホルムアルデヒド、フェノー
ルを縮合させた後脱水しフルフリルァルコールを添加し
共縮合させる製造法が一般的である。上記製造法におい
て脱水工程後更にフルフリルアルコールを添加し共縮合
させる製造法は脱水時に反応装置内の配合量が少ないた
め池珠現象、飛沫同伴の影響を受けにくく脱水工程後に
フルフリルアルコールを添加しない製造法に比べ同一容
量の反応装置では多量の製造が可能となり工業的には非
常に経済的で有効な製造法である。本発明者らは鋳型製
造時の悪臭の原因について検討した結果、前記樹脂製造
工程において脱水工程後に添加する工業用フルフリルア
ルコール中の低沸点分に起因することを見し、出し本発
明にいたつた。Further, for furfuryl alcohol/formaldehyde/phenol co-condensation resin, a common manufacturing method is to condense formaldehyde and phenol, dehydrate them, add furfuryl alcohol, and co-condense the resin. In the above manufacturing method, furfuryl alcohol is further added after the dehydration step and co-condensed. Because the amount of compounded in the reaction device is small during dehydration, it is less susceptible to the effects of the Ikebama phenomenon and droplet entrainment, and furfuryl alcohol is not added after the dehydration step. Compared to the production method, it is possible to produce a large amount using a reactor of the same capacity, making it a very economical and effective production method from an industrial perspective. As a result of investigating the cause of the bad odor during mold manufacturing, the present inventors found that it is caused by the low boiling point content of industrial furfuryl alcohol added after the dehydration step in the resin manufacturing process, and developed the present invention. Ivy.
樹脂製造に使用する工業用フルフリルアルコールは工業
的にはフルフラールの還元によって得られている。Industrial furfuryl alcohol used in resin production is obtained industrially by reduction of furfural.
しかしこの還元時には部分的に更に還元が進行して２ー
メチルフランおよびテトラヒドロフルフリルアルコール
等の副生物を生じる。また原料のフルフラールもフルフ
リルアルコール中に残存してしまう。これらフルフラー
ル、テトラヒドロフルフリルアルコールおよび２ーメチ
ルフラン等の工業用フルフリルアルコール中の低沸点分
が刺激臭の主な原因であり、本発明においてはこれらの
低沸点分を目硬性鋳型用粘結剤の製造工程中に留出除去
することを特徴とする。However, during this reduction, further reduction partially proceeds to produce by-products such as 2-methylfuran and tetrahydrofurfuryl alcohol. Further, the raw material furfural also remains in the furfuryl alcohol. These low boiling point components in industrial furfuryl alcohols such as furfural, tetrahydrofurfuryl alcohol, and 2-methylfuran are the main cause of the irritating odor, and in the present invention, these low boiling point components are used as a binder for hard molds. It is characterized by being removed by distillation during the manufacturing process.
すなわち、本発明はフルフリルアルコール、尿素および
フェノールから選ばれる少くとも１種以上とホルムアル
デヒドを反応させた後脱水し、次いで工業用フルフリル
アルコールを添加反応させ、次いで配合した工業用フル
フリルアルコール量の１〜１の重量％に相当する低沸点
分を共沸蒸留または減圧濃縮により留出除去することを
特徴とする。That is, the present invention involves reacting formaldehyde with at least one selected from furfuryl alcohol, urea, and phenol, followed by dehydration, then adding and reacting industrial furfuryl alcohol, and then reducing the amount of industrial furfuryl alcohol blended. It is characterized in that a low-boiling point component corresponding to 1 to 1% by weight of the amount of water is removed by distillation by azeotropic distillation or vacuum concentration.
通常工業用フルフリルアルコール中の低沸点分をフルフ
リルアルコール製造時に蒸留により除去した場合、これ
ら低沸点分の含有量が少ないため低沸点分だけを分留す
ることは困難であり、実際にはフルフリルアルコールが
一部、低沸点分とともに除去され収量が低下し、このよ
うにして得られた高純度フルフリルアルコールは高価な
ものとなりこれを使用した場合、製品価格の上昇につな
がる。If the low boiling point components of industrial furfuryl alcohol are removed by distillation during the production of furfuryl alcohol, it is difficult to fractionally distill only the low boiling point components because the content of these low boiling point components is small; A portion of furfuryl alcohol is removed along with the low-boiling point components, resulting in a decrease in yield, and the high purity furfuryl alcohol thus obtained is expensive, leading to an increase in the price of the product if it is used.
本発明では安価な低沸点分を含む工業用フルフリルアル
コールを使用し目硬性鋳型用粘緒剤の製造工程中に共縦
蒸留または減圧濃縮により工業用フルフリルアルコール
中の低沸点分を留出除去し刺激臭の少ない目硬性鋳型用
粘結剤を得ることを可能にしたもので本発明の場合、フ
ルフリルァルコール製造時に蒸留にて低沸点分を除去す
る方法に比べ、フルフリルアルコールが反応し樹脂化し
ているため低沸点分とともに除去されにくくなっており
フルフリルアルコールの損失を防げ、また同一容量の反
応装置で多量の製造ができる製造法の特色を損うことも
なくなお且つ高価な高純度フルフリルアルコールを使用
せず刺激臭の少ない目硬性鋳型用粘給剤を得ることがで
きその効果は大きい。本発明において、工業用フルフリ
ルアルコール添加前のフルフリルアルコール・尿素・ホ
ルムアルデヒド共縮合樹脂、フルフリルアルコール・フ
ェ／一ル・ホルムアルデヒド共縮合樹脂等の共縮合樹脂
の合成は通常行われている条件下で反応させる。In the present invention, industrial furfuryl alcohol containing an inexpensive low-boiling point component is used, and the low-boiling point component in the industrial furfuryl alcohol is distilled out by co-vertical distillation or vacuum concentration during the manufacturing process of a sticky agent for hard molds. In the case of the present invention, furfuryl alcohol is removed compared to the method of removing low boiling point components by distillation during the production of furfuryl alcohol. Because it reacts and becomes a resin, it becomes difficult to remove along with the low-boiling point components, which prevents the loss of furfuryl alcohol, and also does not impair the characteristics of the manufacturing method, which allows large quantities to be produced using the same capacity reactor, and is also expensive. It is possible to obtain a viscous agent for hard molds with less irritating odor without using high-purity furfuryl alcohol, and the effect is great. In the present invention, the synthesis of co-condensed resins such as furfuryl alcohol/urea/formaldehyde co-condensed resin and furfuryl alcohol/fer/formaldehyde co-condensed resin before addition of industrial furfuryl alcohol is carried out under the usual conditions. React below.
すなわちフルフリルアルコール・尿素・およびフェノー
ルから選ばれる少くとも１種以上とホルムアルデヒドを
アンモニア、水酸化ナトリウム、トリメチルアミン等の
塩基触媒使用で反応させる。または塩基触媒使用で反応
後、塩酸、シュウ酸、パラトルェンスルホン酸等の酸性
触媒を用い更に反応させる。フルフリルアルコールは高
純度のものを用いてもよいし、工業用フルフリルアルコ
ールを用いてもよい。脱水工程後に添加される工業用フ
ルフリルアルコールは２−メチルフラン、テトラヒドロ
フルフリルアルコール、フルフラール等を０．１〜５％
含む工業的に生産されたフルフリルアルコールを意味す
る。その使用量はフルフリルアルコール、尿素、フェノ
ール等１モルに対して１〜３０モルである。反応は６０
〜１０５ｏｏで０．２〜５時間行ない、その後次の工程
にうつる。共漆蒸留または減圧濃縮で留出除去する量は
配合したフルフリルアルコール量の１〜１の重量％とす
る。That is, at least one member selected from furfuryl alcohol, urea, and phenol is reacted with formaldehyde using a base catalyst such as ammonia, sodium hydroxide, or trimethylamine. Alternatively, after reaction using a base catalyst, further reaction is performed using an acidic catalyst such as hydrochloric acid, oxalic acid, para-toluenesulfonic acid, or the like. Furfuryl alcohol of high purity may be used, or industrial furfuryl alcohol may be used. Industrial furfuryl alcohol added after the dehydration process contains 0.1 to 5% of 2-methylfuran, tetrahydrofurfuryl alcohol, furfural, etc.
means industrially produced furfuryl alcohol containing The amount used is 1 to 30 moles per mole of furfuryl alcohol, urea, phenol, etc. The reaction is 60
- 105 oo for 0.2 to 5 hours, and then proceed to the next step. The amount to be removed by co-lacquer distillation or vacuum concentration is 1 to 1% by weight of the amount of furfuryl alcohol blended.
これはフルフリルアルコール中の低沸点分と縮合水が同
時に共瀕して蟹出するためであり、留出量が１重量％未
満では低沸点分除去の効果が少なく１の重量％を越える
と製品の収量が低下し経済的ではなくなる。共沸蒸留の
操作としては常圧で液温を１０５〜１３０ｑｏまで昇温
し配合したフルフリルアルコール量の１〜１の重量％に
相当する量の留出液が得られたらこれを除去すればよい
。減圧濃縮の場合は液温６０ｑＣ以上、減圧度４０仇肌
日製〆上の条件で低沸点分を除去できる。本発明により
低価格の工業用フルフリルアルコールを使用し刺激臭の
少ない目硬性鋳型用粘結剤を得ることができた。This is because the low-boiling point components and condensed water in furfuryl alcohol co-extract at the same time, and if the distillation amount is less than 1% by weight, the effect of removing the low-boiling point components is small, and if it exceeds 1% by weight, Product yield decreases and becomes uneconomical. The operation of azeotropic distillation is to raise the liquid temperature to 105 to 130 qo at normal pressure and remove the distillate when an amount of distillate corresponding to 1 to 1% by weight of the amount of furfuryl alcohol blended is obtained. good. In the case of vacuum concentration, low boiling point components can be removed under the conditions of a liquid temperature of 60 qC or higher and a vacuum degree of 40 qC or higher. According to the present invention, it was possible to obtain a binder for hard molds with less irritating odor using low-cost industrial furfuryl alcohol.
以下実施例に基いて説明する。The following will be explained based on examples.
実施例 １
還流冷却器、額洋装層、温度計を備えた四つ口フラスコ
に尿素１２０夕、３７％ホルマリン３５６夕、工業用フ
ルフリルアルコール５機夕、１０％水酸化ナトリウム水
溶液０．６夕を入れ９０ｏ０で３０分反応させた後、８
％塩酸水溶液１．８夕を添加し更に９０００で１時間反
応後、減圧度６００〜７０仇吻Ｈｇで脱水濃縮し尿素変
性フラン樹脂を得た。Example 1 In a four-necked flask equipped with a reflux condenser, a Western-style layer, and a thermometer, 120 hours of urea, 356 hours of 37% formalin, 5 hours of industrial furfuryl alcohol, and 0.6 hours of 10% aqueous sodium hydroxide solution were added. After reacting at 90o0 for 30 minutes,
After adding 1.8% aqueous hydrochloric acid solution and reacting for 1 hour at 9,000℃, the mixture was dehydrated and concentrated at a reduced pressure of 600 to 70℃ to obtain a urea-modified furan resin.
これに工業用フルフリルアルコール３９２夕、シュウ酸
１．４夕を添加し９０℃で１時間反応させその後内溢を
１２０℃まで昇温して共沸蒸留を行ない２４夕の蟹出液
を除去して目硬性鋳型用粘結剤を得た。．実施例 ２
還流冷却器、瀦洋装贋、温度計を備えた四つ口フラスコ
にフヱノール１８８夕、８０％バラホルム７６夕、３７
％ホルマリン１３０夕、２５％アンモニア水溶液３．１
夕を入れ７０００で２間反応させた後、減圧度６００〜
７００柳Ｈｇで脱水濃縮しレゾール型フェノ−ル樹脂を
得た。To this, 392 liters of industrial furfuryl alcohol and 1.4 liters of oxalic acid were added and reacted at 90℃ for 1 hour, then the temperature was raised to 120℃ and azeotropic distillation was performed to remove the 24 liters of crab exudate. A binder for hard molds was obtained. ．． Example 2 Into a four-necked flask equipped with a reflux condenser, a thermometer and a thermometer, 188% of phenol, 76% of 80% roseform, and 37% of phenol were added.
% formalin 130%, 25% ammonia aqueous solution 3.1
After reacting for 2 hours at 7000℃, the degree of decompression is 600~
It was dehydrated and concentrated at 700 Yanagi Hg to obtain a resol type phenolic resin.
これに工業用フルフリルアルコール２９４夕を添加後５
０午○で３０分反応した後、減圧度５００〜６００肋Ｈ
ｇ、内温６５〜７５℃で減圧濃縮し、２６夕の蟹出液を
除去し目硬性鋳型用粘結剤を得た。比較例 １還流冷却
器、櫨洋装直、温度計を備えた四つ口フラスコに尿素１
２０夕、３７％ホルマリン３５６夕、工業用フルフリル
アルコール５８８夕、１０％水酸化ナトリウム水溶液０
．６夕を入れ９０℃で３０分反応させた後、８％塩酸水
溶液１．８夕を添加し更に９０℃で１時間反応後、減圧
度６００〜７０仇舷Ｈｇで脱水濃縮し尿素変性フラン樹
脂を得た。After adding 294 grams of industrial furfuryl alcohol to this,
After reacting for 30 minutes at 0:00 pm, the degree of vacuum is 500-600 H.
The mixture was concentrated under reduced pressure at an internal temperature of 65 to 75°C, and the crab exudate of 26 days was removed to obtain a hard mold binder. Comparative Example 1 1 urea was added to a four-necked flask equipped with a reflux condenser, a cylindrical jacket, and a thermometer.
20 minutes, 37% formalin 356 hours, industrial furfuryl alcohol 588 hours, 10% sodium hydroxide aqueous solution 0
．． After reacting at 90℃ for 30 minutes, 1.8 minutes of 8% aqueous hydrochloric acid solution was added, and after further reaction at 90℃ for 1 hour, the urea-modified furan resin was dehydrated and concentrated at a reduced pressure of 600 to 70 degrees Hg. I got it.
これに工業用フルフリルアルコール３９２夕、シュウ酸
１．４２を添加し９０℃で１時間反応させ目硬性鋳型用
粘結剤を得た。比較例 ２
還流冷却器、櫨洋装層、温度計を備えた四つ口フラスコ
にフェノール１磯夕、８０％パラホルム７６夕、３７％
ホルマリン１３０夕、２５％アンモニア水溶液３．１夕
を入れ７０００で２時間反応させた後、減圧度６００〜
７０動脈Ｈｇで脱水濃縮しレゾール型フェ／ール樹脂を
得た。To this, 392 g of industrial furfuryl alcohol and 1.4 g of oxalic acid were added and reacted at 90° C. for 1 hour to obtain a hard mold binder. Comparative Example 2 In a four-necked flask equipped with a reflux condenser, a layer of oak clothing, and a thermometer, 1 phenol, 80% paraform, 76 %, and 37% paraform were added.
After adding formalin for 130 hours and 3.1 hours of 25% ammonia aqueous solution and reacting at 7000 for 2 hours, the degree of vacuum was 600~
It was dehydrated and concentrated at 70 arterial Hg to obtain a resol type fer/fer resin.
これに工業用フルフリルアルコール２９４夕を添加し５
０００で３び分間反応し目硬性鋳型用粘結剤を得た。上
読谷樹脂を比較対照するため１４あの容積を持つ試験室
内で混練機に珪砂５ｋｇおよび７５％パラトルエンスル
ホン酸水溶液３０夕を入れて３町皆蝿拝漉練した後、上
記実施例および比較例で得られた樹脂７５夕を添加し６
現砂、間額浮浪糠し目硬性鋳型用鋳物砂を得た。Add 294 grams of industrial furfuryl alcohol to this and
000 for 3 minutes to obtain a hard mold binder. In order to compare and contrast Kamiyomitan resin, 5 kg of silica sand and 30 minutes of 75% para-toluene sulfonic acid aqueous solution were put into a kneading machine in a test room with a capacity of 14 hours, and the mixture was mixed with the above Examples and Comparative Examples. Add 75% of the resin obtained in 6
Existing sand and hard molding sand for molds were obtained.
この得られた目硬性鋳型用鋳物砂を試験室内の床上に厚
さ１肌に広げ３分間、７人の人間による感応試験を行な
った。The obtained hard molding sand was spread on the floor of the test chamber to a thickness of 1 skin, and a sensitivity test was conducted by 7 people for 3 minutes.
試験は１回ごとに試験室内の換気を行ない試験者は過去
に目硬性鋳型用半占繕剤の製造または使用の経験の無い
者を選んだ。試験結果を下表に示した。表−１
表−２The test room was ventilated after each test, and testers were selected who had no past experience in manufacturing or using semi-preservatives for hard molds. The test results are shown in the table below. Table-1 Table-2
Claims (1)
選ばれる少なくとも１種以上とホルムアルデヒドを反応
させた後脱水し、次いで工業用フルフリルアルコールを
添加反応させ、次いで配合して工業用フルフリルアルコ
ール量の１〜１０重量％に相当する低沸点分を共沸蒸留
または減圧濃縮により留出除去することを特徴とする自
硬性鋳型用粘結剤の製造法。1. After reacting formaldehyde with at least one selected from furfuryl alcohol, urea and phenol, dehydration is performed, and then industrial furfuryl alcohol is added and reacted, and then blended to give an amount of 1 to 10 of industrial furfuryl alcohol. A method for producing a self-hardening binder for molds, which comprises distilling and removing a low-boiling point component corresponding to % by weight by azeotropic distillation or vacuum concentration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1976681A JPS6020110B2 (en) | 1981-02-12 | 1981-02-12 | Manufacturing method of self-hardening mold binder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1976681A JPS6020110B2 (en) | 1981-02-12 | 1981-02-12 | Manufacturing method of self-hardening mold binder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57134234A JPS57134234A (en) | 1982-08-19 |
| JPS6020110B2 true JPS6020110B2 (en) | 1985-05-20 |
Family
ID=12008454
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1976681A Expired JPS6020110B2 (en) | 1981-02-12 | 1981-02-12 | Manufacturing method of self-hardening mold binder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6020110B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4108270A1 (en) * | 1991-03-14 | 1992-09-17 | Gewerk Keramchemie | TURABLE DIMENSIONS |
| KR101592882B1 (en) * | 2014-06-27 | 2016-02-15 | 주식회사 퓨어스피어 | Manufacturing method for spherical particle of furan resin |
-
1981
- 1981-02-12 JP JP1976681A patent/JPS6020110B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57134234A (en) | 1982-08-19 |
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