JPH0464764B2 - - Google Patents
Info
- Publication number
- JPH0464764B2 JPH0464764B2 JP12129783A JP12129783A JPH0464764B2 JP H0464764 B2 JPH0464764 B2 JP H0464764B2 JP 12129783 A JP12129783 A JP 12129783A JP 12129783 A JP12129783 A JP 12129783A JP H0464764 B2 JPH0464764 B2 JP H0464764B2
- Authority
- JP
- Japan
- Prior art keywords
- acid
- urea
- weight
- resins
- methylolacrylamide
- 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
- XPFVYQJUAUNWIW-UHFFFAOYSA-N furfuryl alcohol Chemical compound OCC1=CC=CO1 XPFVYQJUAUNWIW-UHFFFAOYSA-N 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 15
- 229920005989 resin Polymers 0.000 claims description 15
- 239000011347 resin Substances 0.000 claims description 15
- CNCOEDDPFOAUMB-UHFFFAOYSA-N N-Methylolacrylamide Chemical compound OCNC(=O)C=C CNCOEDDPFOAUMB-UHFFFAOYSA-N 0.000 claims description 14
- 239000004576 sand Substances 0.000 claims description 11
- 239000011230 binding agent Substances 0.000 claims description 8
- 239000007849 furan resin Substances 0.000 claims description 7
- 239000004202 carbamide Substances 0.000 claims description 5
- XSQUKJJJFZCRTK-UHFFFAOYSA-N urea group Chemical group NC(=O)N XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 5
- 239000005011 phenolic resin Substances 0.000 claims description 4
- 229920001568 phenolic resin Polymers 0.000 claims description 4
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 claims 1
- 239000002253 acid Substances 0.000 claims 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 229920001807 Urea-formaldehyde Polymers 0.000 description 6
- 239000003054 catalyst Substances 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 3
- 150000002240 furans Chemical class 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- JOXIMZWYDAKGHI-UHFFFAOYSA-N toluene-4-sulfonic acid Chemical compound CC1=CC=C(S(O)(=O)=O)C=C1 JOXIMZWYDAKGHI-UHFFFAOYSA-N 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000006087 Silane Coupling Agent Substances 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- WYTZZXDRDKSJID-UHFFFAOYSA-N (3-aminopropyl)triethoxysilane Chemical compound CCO[Si](OCC)(OCC)CCCN WYTZZXDRDKSJID-UHFFFAOYSA-N 0.000 description 1
- JIRHAGAOHOYLNO-UHFFFAOYSA-N (3-cyclopentyloxy-4-methoxyphenyl)methanol Chemical compound COC1=CC=C(CO)C=C1OC1CCCC1 JIRHAGAOHOYLNO-UHFFFAOYSA-N 0.000 description 1
- PAWQVTBBRAZDMG-UHFFFAOYSA-N 2-(3-bromo-2-fluorophenyl)acetic acid Chemical compound OC(=O)CC1=CC=CC(Br)=C1F PAWQVTBBRAZDMG-UHFFFAOYSA-N 0.000 description 1
- SJECZPVISLOESU-UHFFFAOYSA-N 3-trimethoxysilylpropan-1-amine Chemical compound CO[Si](OC)(OC)CCCN SJECZPVISLOESU-UHFFFAOYSA-N 0.000 description 1
- UUEWCQRISZBELL-UHFFFAOYSA-N 3-trimethoxysilylpropane-1-thiol Chemical compound CO[Si](OC)(OC)CCCS UUEWCQRISZBELL-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 229920000877 Melamine resin Polymers 0.000 description 1
- 229930040373 Paraformaldehyde Natural products 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- SRSXLGNVWSONIS-UHFFFAOYSA-N benzenesulfonic acid Chemical compound OS(=O)(=O)C1=CC=CC=C1 SRSXLGNVWSONIS-UHFFFAOYSA-N 0.000 description 1
- 229940092714 benzenesulfonic acid Drugs 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- WSFSSNUMVMOOMR-UHFFFAOYSA-N formaldehyde Substances O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 1
- HDNHWROHHSBKJG-UHFFFAOYSA-N formaldehyde;furan-2-ylmethanol Chemical compound O=C.OCC1=CC=CO1 HDNHWROHHSBKJG-UHFFFAOYSA-N 0.000 description 1
- SLGWESQGEUXWJQ-UHFFFAOYSA-N formaldehyde;phenol Chemical compound O=C.OC1=CC=CC=C1 SLGWESQGEUXWJQ-UHFFFAOYSA-N 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- MQWFLKHKWJMCEN-UHFFFAOYSA-N n'-[3-[dimethoxy(methyl)silyl]propyl]ethane-1,2-diamine Chemical compound CO[Si](C)(OC)CCCNCCN MQWFLKHKWJMCEN-UHFFFAOYSA-N 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 229920002866 paraformaldehyde Polymers 0.000 description 1
- ODGAOXROABLFNM-UHFFFAOYSA-N polynoxylin Chemical compound O=C.NC(N)=O ODGAOXROABLFNM-UHFFFAOYSA-N 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000011134 resol-type phenolic resin Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- BPSIOYPQMFLKFR-UHFFFAOYSA-N trimethoxy-[3-(oxiran-2-ylmethoxy)propyl]silane Chemical compound CO[Si](OC)(OC)CCCOCC1CO1 BPSIOYPQMFLKFR-UHFFFAOYSA-N 0.000 description 1
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
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)
- Compositions Of Macromolecular Compounds (AREA)
Description
本発明は酸硬化型鋳物砂用粘結剤組成物に関す
るものである。
更に詳しくは本発明は酸硬化型樹脂にＮ−メチ
ロールアクリルアミドを添加溶解してなる鋳型強
度を向上させる鋳物砂用粘結剤組成物に関するも
のである。
鋳型および中子の製造に使用される粘結剤とし
て従来よりフエノール樹脂、フラン樹脂、尿素樹
脂、メラミン樹脂又はその変性物が用いられてい
ることは公知である。特に、フエノール樹脂やフ
ラン樹脂については、粘結剤の低廉化、鋳型割れ
の改善や注湯後の鋳型崩壊性の改善を目的にフル
フリルアルコール−尿素−ホルムアルデヒド、フ
エノール−尿素−ホルムアルデヒドやフルフリル
アルコール−フエノール−尿素−ホルムアルデヒ
ドの各成分を縮合した尿素変性樹脂が広く使用さ
れている。
しかし、これら尿素変性樹脂においては、その
尿素変性の度合を大きくすることは、鋳型強度・
表面安定度の低下、貯蔵中の不溶性沈殿物の発生
或いは再生砂中の窒素含有量増大による鋳物欠陥
の発生等の問題が生じる。
本発明者はかかる尿素変性樹脂の欠点を改良す
べく種々検討した結果、尿素成分の全て又はその
一部の代わりにＮ−メチロールアクリルアミドを
添加溶解することにより、尿素変性樹脂の利点を
損なうことなく鋳型強度を向上させ、貯蔵中の不
溶性沈殿物の発生もなく、しかも尿素変性樹脂に
比らべ単位重量当りの窒素含有量が小さい為再生
砂中の窒素含有量を著しく低減出来、更に尿素変
性樹脂に比較して低粘度で取扱いも容易である鋳
物砂用粘結剤組成物を見い出し本発明に到着し
た。
即ち、本発明は酸硬化型樹脂に対しＮ−メチロ
ールアクリルアミドを酸硬化型樹脂とＮ−メチロ
ールアクリルアミドの混合物中の含有量が２〜50
重量％となる様添加溶解してなる酸硬化型鋳物砂
用粘結剤組成物を提供するものである。
本発明の組成物中のＮ−メチロールアクリルア
ミドの含有量の範囲は尿素変性樹脂に比らべ広
く、実用上は酸硬化型樹脂−Ｎ−メチロールアク
リルアミド混合物中２〜50重量％、好ましくは２
〜40重量％である。２重量％未満では効果が小さ
く、50重量％を越えると鋳型強度の低下がみられ
る。
尚、更に鋳型強度を向上させる目的で本組成物
中にシランカツプリング剤を含有することも出来
る。シランカツプリンク剤としては、γ−（２−
アミノエチル）アミノプロピルメチルジメトキシ
シラン、γ−アミノプロピルトリメトキシシラ
ン、γ−アミノプロピルトリエトキシシラン、γ
−メルカプトプロピルトリメトキシシラン、γ−
グリシドキシプロピルトリメトキシシラン等が挙
げられる。
本発明に用いられる酸硬化型樹脂としては、フ
ルフリルアルコール、或いはフルフリルアルコー
ル−ホルムアルデヒド、フルフリルアルコール−
尿素−ホルムアルデヒド、フエノール−ホルムア
ルデヒド、フエノール−尿素−ホルムアルデヒド
の各成分を縮合したフラン樹脂、フエノール樹脂
及びそれらの尿素変性樹脂が使用できる。
本発明の粘結剤組成物の酸性硬化触媒としては
塩化アンモニウム、硝酸アンモニウム、塩化第二
鉄、リン酸、塩酸、硫酸、パラトルエンスルホン
酸、ベンゼンスルホン酸、キシレンスルホン酸等
の有機酸、無機酸およびこれらの塩類が使用でき
る。
以下本発明の詳細について実施例をもつて説明
する。
実施例 １〜４
常法により、フルフリルアルコール中で尿素お
よびパラホルムアルデヒドをモル比１／２で塩基
性触媒下、80℃30分間反応させ、更に酸性触媒下
80℃２時間反応させて種々変性率の尿素変性フラ
ン樹脂を得た。
前記尿素変性フラン樹脂およびフルフリルアル
コールにＮ−メチロールアクリルアミドを添加溶
解し、その混合物の保存安定性を観察した。結果
を表−１に示す。尚、Ｎ−メチロールアクリルア
ミドを添加溶解しなかつた尿素変性フラン樹脂に
ついての結果を比較例１〜３として示した。
The present invention relates to an acid-curing binder composition for foundry sand. More specifically, the present invention relates to a binder composition for foundry sand that improves mold strength and is made by adding and dissolving N-methylolacrylamide in an acid-curable resin. It is well known that phenolic resins, furan resins, urea resins, melamine resins, or modified products thereof have been used as binders for manufacturing molds and cores. In particular, for phenolic resins and furan resins, furfuryl alcohol-urea-formaldehyde, phenol-urea-formaldehyde and furfuryl Urea-modified resins, which are obtained by condensing each component of alcohol, phenol, urea, and formaldehyde, are widely used. However, in these urea-modified resins, increasing the degree of urea modification is important for mold strength and
Problems arise such as a decrease in surface stability, the formation of insoluble precipitates during storage, or the occurrence of casting defects due to an increase in nitrogen content in the reclaimed sand. As a result of various studies aimed at improving the drawbacks of such urea-modified resins, the present inventors discovered that by adding and dissolving N-methylol acrylamide in place of all or part of the urea component, the advantages of urea-modified resins are not impaired. It improves mold strength, does not generate insoluble precipitates during storage, and has a lower nitrogen content per unit weight than urea-modified resin, so the nitrogen content in recycled sand can be significantly reduced. The present invention has been accomplished by discovering a binder composition for foundry sand that has a lower viscosity than resins and is easier to handle. That is, in the present invention, the content of N-methylol acrylamide in the acid-curable resin and N-methylol acrylamide in the mixture of the acid-curable resin and N-methylol acrylamide is 2 to 50
The object of the present invention is to provide an acid-curing binder composition for foundry sand, which is obtained by adding and dissolving the composition in such a manner that the composition becomes % by weight. The content range of N-methylolacrylamide in the composition of the present invention is wider than that of urea-modified resin, and in practical terms it is 2 to 50% by weight, preferably 2 to 50% by weight in the acid-curable resin-N-methylolacrylamide mixture.
~40% by weight. If it is less than 2% by weight, the effect will be small, and if it exceeds 50% by weight, the mold strength will decrease. Incidentally, a silane coupling agent may also be included in the present composition for the purpose of further improving mold strength. As a silane coupling agent, γ-(2-
aminoethyl)aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ
-Mercaptopropyltrimethoxysilane, γ-
Examples include glycidoxypropyltrimethoxysilane. The acid-curable resin used in the present invention includes furfuryl alcohol, furfuryl alcohol-formaldehyde, and furfuryl alcohol-formaldehyde.
Furan resins, phenol resins, and urea-modified resins thereof, which are obtained by condensing each component of urea-formaldehyde, phenol-formaldehyde, and phenol-urea-formaldehyde, can be used. Examples of acidic curing catalysts for the binder composition of the present invention include organic acids and inorganic acids such as ammonium chloride, ammonium nitrate, ferric chloride, phosphoric acid, hydrochloric acid, sulfuric acid, para-toluenesulfonic acid, benzenesulfonic acid, and xylenesulfonic acid. and these salts can be used. The details of the present invention will be explained below using examples. Examples 1 to 4 By a conventional method, urea and paraformaldehyde were reacted in furfuryl alcohol at a molar ratio of 1/2 under a basic catalyst at 80°C for 30 minutes, and then under an acidic catalyst.
The reaction was carried out at 80°C for 2 hours to obtain urea-modified furan resins with various modification rates. N-methylolacrylamide was added and dissolved in the urea-modified furan resin and furfuryl alcohol, and the storage stability of the mixture was observed. The results are shown in Table-1. The results for urea-modified furan resins in which N-methylolacrylamide was not added and dissolved are shown as Comparative Examples 1 to 3.
【表】
実施例 ５〜８
鋳物砂100重量部に対し、硬化触媒としてパラ
トルエンスルホン酸の75％水溶液を0.4重量部添
加し、１分間混合する。そののち、Ｎ−メチロー
ルアクリルアミドを添加溶解したフルフリルアル
コールを１重量部１分間混合する。この混合砂で
テストピースを作成し、その鋳型強度及び崩壊性
を測定した。結果を表−２に示す。尚、Ｎ−メチ
ロールアクリルアミドを添加しない系を比較例４
として示した。[Table] Examples 5 to 8 To 100 parts by weight of foundry sand, 0.4 parts by weight of a 75% aqueous solution of para-toluenesulfonic acid was added as a curing catalyst and mixed for 1 minute. Thereafter, 1 part by weight of furfuryl alcohol in which N-methylolacrylamide was added and dissolved was mixed for 1 minute. A test piece was prepared using this mixed sand, and its mold strength and collapsibility were measured. The results are shown in Table-2. In addition, Comparative Example 4 is a system in which N-methylol acrylamide is not added.
It was shown as
【表】
実施例 ９〜12
鋳物砂100重量部に対し、硬化触媒としてパラ
トルエンスルホン酸の75％水溶液を0.5重量部加
え１分間混合した後、Ｎ−メチロールアクリルア
ミドを添加溶解したレゾール型フエノール樹脂を
1.2重量部加え１分間混合した。この混練砂でテ
ストピースを作成した後、その鋳型強度及び崩壊
性を測定した。結果を表−３に示す。尚、Ｎ−メ
チロールアクリルアミドを添加しない系を比較例
５として示した。[Table] Examples 9 to 12 Resol type phenolic resin in which 0.5 parts by weight of a 75% aqueous solution of para-toluenesulfonic acid as a curing catalyst was added to 100 parts by weight of foundry sand, mixed for 1 minute, and then N-methylolacrylamide was added and dissolved. of
1.2 parts by weight was added and mixed for 1 minute. After creating a test piece using this kneaded sand, its mold strength and collapsibility were measured. The results are shown in Table-3. A system in which N-methylolacrylamide was not added was shown as Comparative Example 5.
Claims (1)
アミドを、酸硬化型樹脂とＮ−メチロールアクリ
ルアミドの混合物中の含有量が２〜50重量％とな
る様添加溶解してなる酸硬化型鋳物砂用粘結剤組
成物。 ２ 酸硬化型樹脂がフラン樹脂、フエノール樹脂
およびフルフリルアルコールの夫々単独又は尿素
で変性された樹脂である特許請求の範囲第１項記
載の粘結剤組成物。[Scope of Claims] 1. Acid curing made by adding and dissolving N-methylolacrylamide to an acid-curing resin so that the content in the mixture of the acid-curing resin and N-methylolacrylamide is 2 to 50% by weight. Binder composition for mold foundry sand. 2. The binder composition according to claim 1, wherein the acid-curable resin is a furan resin, a phenolic resin, and a furfuryl alcohol, each alone or modified with urea.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12129783A JPS6012249A (en) | 1983-07-04 | 1983-07-04 | Binder composition for molding sand |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12129783A JPS6012249A (en) | 1983-07-04 | 1983-07-04 | Binder composition for molding sand |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6012249A JPS6012249A (en) | 1985-01-22 |
| JPH0464764B2 true JPH0464764B2 (en) | 1992-10-16 |
Family
ID=14807770
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12129783A Granted JPS6012249A (en) | 1983-07-04 | 1983-07-04 | Binder composition for molding sand |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6012249A (en) |
-
1983
- 1983-07-04 JP JP12129783A patent/JPS6012249A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6012249A (en) | 1985-01-22 |
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