DE2039330A1 - Polyurethane bound sand casting composn-contg a ketone - /formaldehyde resin for longer pot life - Google Patents
Polyurethane bound sand casting composn-contg a ketone - /formaldehyde resin for longer pot lifeInfo
- Publication number
- DE2039330A1 DE2039330A1 DE19702039330 DE2039330A DE2039330A1 DE 2039330 A1 DE2039330 A1 DE 2039330A1 DE 19702039330 DE19702039330 DE 19702039330 DE 2039330 A DE2039330 A DE 2039330A DE 2039330 A1 DE2039330 A1 DE 2039330A1
- Authority
- DE
- Germany
- Prior art keywords
- ketone
- composn
- pot life
- sand
- formaldehyde
- 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.)
- Granted
Links
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 title claims abstract description 28
- 229920005989 resin Polymers 0.000 title claims abstract description 10
- 239000011347 resin Substances 0.000 title claims abstract description 10
- 229920002635 polyurethane Polymers 0.000 title claims description 6
- 239000004814 polyurethane Substances 0.000 title claims description 6
- 150000002576 ketones Chemical class 0.000 title description 5
- 238000007528 sand casting Methods 0.000 title 1
- 239000000203 mixture Substances 0.000 claims abstract description 22
- 238000000465 moulding Methods 0.000 claims abstract description 18
- 239000004576 sand Substances 0.000 claims abstract description 7
- 125000003118 aryl group Chemical group 0.000 claims abstract description 5
- 239000012948 isocyanate Substances 0.000 claims abstract description 5
- 150000002513 isocyanates Chemical class 0.000 claims abstract description 5
- 150000001875 compounds Chemical class 0.000 claims description 9
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 6
- -1 aliphatic ketones Chemical class 0.000 claims description 5
- 239000007859 condensation product Substances 0.000 claims description 5
- 125000001931 aliphatic group Chemical group 0.000 claims 1
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 abstract description 6
- 239000011261 inert gas Substances 0.000 abstract description 4
- 238000005452 bending Methods 0.000 abstract description 3
- LNWBFIVSTXCJJG-UHFFFAOYSA-N [diisocyanato(phenyl)methyl]benzene Chemical compound C=1C=CC=CC=1C(N=C=O)(N=C=O)C1=CC=CC=C1 LNWBFIVSTXCJJG-UHFFFAOYSA-N 0.000 abstract description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 2
- 150000001412 amines Chemical class 0.000 abstract 1
- RXKJFZQQPQGTFL-UHFFFAOYSA-N dihydroxyacetone Chemical compound OCC(=O)CO RXKJFZQQPQGTFL-UHFFFAOYSA-N 0.000 abstract 1
- 238000010438 heat treatment Methods 0.000 abstract 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 4
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- 150000003512 tertiary amines Chemical class 0.000 description 3
- JOYRKODLDBILNP-UHFFFAOYSA-N urethane group Chemical group NC(=O)OCC JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000001476 alcoholic effect Effects 0.000 description 2
- 229920000180 alkyd Polymers 0.000 description 2
- 230000003197 catalytic effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229920001568 phenolic resin Polymers 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 239000006004 Quartz sand Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 230000032050 esterification Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 125000001261 isocyanato group Chemical group *N=C=O 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- DYXKHJNBQMYBHR-UHFFFAOYSA-N n,n-diethylethanamine;propan-2-one;hydrate Chemical compound O.CC(C)=O.CCN(CC)CC DYXKHJNBQMYBHR-UHFFFAOYSA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 150000005846 sugar alcohols Polymers 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
- B22C1/2273—Polyurethanes; Polyisocyanates
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/40—High-molecular-weight compounds
- C08G18/54—Polycondensates of aldehydes
- C08G18/548—Polycondensates of aldehydes with ketones
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Mold Materials And Core Materials (AREA)
Abstract
Description
Formmasse für polyurethangebundene Gießereiformteile Bekannte Formmassen für polyurethangebundene Gießereiformteile sind Mischungen aus Sand, aromatischen mehrfunktionellen Isocyanaten und Phenolformaldehydharzen oder polyamid- und ölmodifizierten Alkydharzen. Die in den bekannten Formmassen enthaltenen Phenolformaldehydharze sind Methylolgruppen aufweisende Kondensationsprodukte aus Phenol und Formaldehyd. Molding compound for polyurethane-bound foundry molded parts Well-known molding compounds for polyurethane-bound foundry molded parts are mixtures of sand, aromatic multifunctional isocyanates and phenol-formaldehyde resins or polyamide- and oil-modified ones Alkyd resins. The phenol-formaldehyde resins contained in the known molding compositions are condensation products of phenol and formaldehyde containing methylol groups.
Die in den bekannten Formmassen enthaltenen polyamid- und ölmodifizierten Alkydharze sind modifizierte Veresterungsprodukte aus mehrwertigen Alkoholen und zweibasischen Carbonsäuren, bei denen alkoholische Hydroxylgruppen unverestert geblieben sind. Beim Härten der aus den bekannten Formmassen geformten Gießereiformteile reagieren die Isocyanatogruppen mit den Methylolgruppen bzw. alkoholischen Hydroxylgruppen in bekannter Weise unter Ausbildung von Urethangruppen. Deshalb sind die Sandkörner in den gehärteten Gießereiformteilen durch Polyurethane gebunden. Die genannten zu Urethangruppen führenden Reaktionen laufen spontan ab, werden nachbekannten Arbeitsmethoden aber auch katalytisch beschleunigt. Als Katalysatoren sind gewisse Peroxide, bestimmte Metallsalze und tertiäre Amine vorbeschrieben. Am häufigsten wird riäthylamin benutzt. Es wird gemeinsam mit inertem Gas, z.B. Stickstoff, durch die zu härtenden, geformten Gießereiformteile, die wegen ihrer körnigen Struktur permeabel sind, hindurchgeblasen.The polyamide- and oil-modified ones contained in the known molding compounds Alkyd resins are modified esterification products made from polyhydric alcohols and dibasic carboxylic acids in which alcoholic hydroxyl groups remained unesterified are. When the foundry moldings hardened from the known molding compounds, they react the isocyanato groups with the methylol groups or alcoholic hydroxyl groups in a known manner with the formation of urethane groups. That is why the grains of sand are bound in the hardened foundry mold parts by polyurethane. The mentioned Reactions leading to urethane groups take place spontaneously and are based on known working methods but also accelerated catalytically. Certain peroxides are used as catalysts, certain Metal salts and tertiary amines described above. The most common use is riethylamine. It is formed together with inert gas, e.g. nitrogen, through the Foundry molded parts because of their granular structure are permeable, blown through.
Alle bekannten Formmassen haben den gemeinsamen Nachteil, daß sie nach dem Anmischen zeitlich nur sehr begrenzt verarbeitbar sind, auch dann, wenn der Katalysator erst zum Zeitpunkt der Formteilfertigung zugeführt wird. Die spontane zu Urethangruppen führende Reaktion verläuft bei den bekannten Formmassen auch ohne Katalysator relativ schnell.In den Gießereien müssen daher häufig Mischungsansätze teilweise weggeworfen werden, weil sie vor dem Hartwerden nicht mehr vollständig verarbeitet werden konnten.All known molding compositions have the common disadvantage that they can only be used for a limited time after mixing, even if the catalyst is only added at the point in time when the molded part is manufactured. The spontaneous one The reaction leading to urethane groups also takes place in the known molding compositions without Catalyst relatively quickly, which is why foundries often have to use mixtures partially thrown away because they are no longer completely before they harden could be processed.
Die vorliegende Erfindung beseitigt diesen Nachteil durch eine Formmasse für polyurdhangebundene Gießereiformteile auf Basis von Mischungen aus Sand, aromatischen mehrfunktionellen Isocyanaten und Harzen mit aliphatisch gebundenen Hydroxylgruppen, dadurch gekennzeichne-t, dass die Harze mit aliphatisch gebundenen Hydroxylgrpen Kondensationsprodukte aus aliphatischen Ketonen und Formaldehyd sind. Das Molverhältnis von Keton : Formaldehyd beträgt vorzugsweise 1 : 2,1 bis 1 : 2,6.The present invention overcomes this disadvantage with a molding compound for polyurethane-bound foundry molded parts based on mixtures of sand, aromatic multifunctional isocyanates and resins with aliphatically bound hydroxyl groups, characterized in that the resins with aliphatically bound hydroxyl groups Are condensation products of aliphatic ketones and formaldehyde. The molar ratio of ketone: formaldehyde is preferably 1: 2.1 to 1: 2.6.
Besonders geeignet sind Kondensationsprodukte aus Me-thylathy; keton und Formaldehyd. Die erfindungsgemäßen Harze werden, sofern sie zu viskos oder fest sind, in Lösungsmitteln gelöst.Condensation products of methylathy are particularly suitable; ketone and formaldehyde. The resins according to the invention, if they are too viscous or solid are dissolved in solvents.
Geeignete Lösungsmittel sind z.B. Ketone, Aromaten oder Gemische aus diesen. Erfindungsgemäße Formmassen, die Mischungen aus Sand, aromatischen mehrfunktionellen Isocyanaten und Keton-Formaldehyd-Kondensationsprodukte bzw. deren Lösungen sind, können bedeutend länger als die bekannten Formmassen gelagert werden, ehe sie unbrauchbar werden. Daraus sollte man folgern können, daß man auch zum Härten der aus den erfindungsgemäßen Formmassen geformten Gießereiformteile wesentlich längere Zeiten benötigt. Dieses trifft überraschenderweise nicht zu.Suitable solvents are e.g. ketones, aromatics or mixtures of this. Molding compositions according to the invention, the mixtures of sand, aromatic multifunctional Are isocyanates and ketone-formaldehyde condensation products or their solutions, can be stored significantly longer than the known molding compounds before they become unusable will. From this one should be able to conclude that one can also harden the from the invention Molding compounds molded foundry parts required much longer times. This surprisingly does not apply.
Das katalytische Härten gelingt bei den erfindungsgemäßen Formmassen genauso schnil wie bei den bekannten Formmassen.Catalytic hardening is successful in the case of the molding compositions according to the invention just as fast as with the known molding compounds.
Das Formen von Gießereiformteilen aus erfindungsgemäßen Formmassen sowie das katalytische Härten der geformten Gießereiformteile geschieht nach bekannten Verfahren. Allerdings kann das Härten auch durch Begasen mit tertiäres Amin enthaltender, Inertgas nach einem angemeldeten Verfahren erfolgen (Patent , Patentanmeldung P 20 35 774.8), das dadurch gekennzeichnet ist, daß das Inertgas mit mehrkomponentigen einphasigen Gemischen in Kontakt gebracht wird, wobei mindestens eine Komponente ein tertiäres Amin und eine andere Komponente Wasser ist.The molding of foundry molded parts from molding compositions according to the invention and the catalytic hardening of the molded foundry parts is done according to known methods Procedure. However, hardening can also be carried out by gassing with tertiary amine-containing, Inert gas according to a pending process (patent, patent application P. 20 35 774.8), which is characterized in that the inert gas with multicomponent single-phase mixtures is brought into contact, with at least one component a tertiary amine and another component is water.
Die folgenden Beispiele sollen die Erfindung erläutern und nicht in ihrer Allgemeingültigkeit beschränken.The following examples are intended to illustrate the invention and not in limit their general validity.
Beispiel 1: 1 Mol Methyläthylketon wurde mit 2,4 Mol Formaldehyd alkalisch solange kondensiert, bis ein Harz mit einer Erweichungstemperatur von ca. 80 0C entstanden war. 70 g einer 40 Obigen Lösung dieses Harzes in Cyclohexanon wurden mit 40 g Diisocyanatodiphenylmethan und 4 kg trockenem Quarzsand in einem Blügelmischer innig vermischt. Aus der Mischung wurden unmittelbar nach dem Mischen und nach dreistundiger Lagerung äe 6 Biegestäbe nach DIN 52 404 geformt und in der Form gelassen. Die Form war abweichend von DIN 52 404 an der Oberseite mit einem Gaszuführungstrichter und an der Unterseite mit Schlitzdüsen versehen worden. ueber den Gaszuführungstrichter wurde 60 sec.Example 1: 1 mol of methyl ethyl ketone became alkaline with 2.4 mol of formaldehyde condensed until a resin with a softening temperature of approx. 80 0C was created. 70 g of the above solution of this resin in cyclohexanone were with 40 g of diisocyanatodiphenylmethane and 4 kg of dry quartz sand in a paddle mixer intimately mixed. The mixture became immediately after mixing and after three hours Storage of 6 bending bars shaped according to DIN 52 404 and left in the mold. Form was different from DIN 52 404 on the top with a gas feed funnel and has been provided with slot nozzles on the underside. via the gas supply funnel was 60 sec.
lang ein mit Triäthylamin beladener Luftstrom durch die in der Form befindliche Mischung wleitet. Die Biegestäbe wurden jeweils nach der Begasung aus der Form genommen, 1 Stunde gelagert und dann nach DIN 52 404 auf Biegefestigkeit geprüft.long a stream of air laden with triethylamine through the in the mold The mixture is located. The bending bars were each made after the gassing Taken from the form, stored for 1 hour and then checked for flexural strength in accordance with DIN 52 404 checked.
Der Mittelwert der Biegefestigkeiten betrug bei den 6 Stäben, die unmittelbar nach dem Mischen hergestellt worden waren, 38,5 kp/cm2 und bei den 6 Stäben, die aus der 3 Stunden gela-2 gerten Mischung hergestellt worden waren, 35,2 kp/cm2.The mean value of the flexural strengths for the 6 rods was were made immediately after mixing, 38.5 kgf / cm2 and the 6 Rods made from the mixture stored for 3 hours, 35.2 kp / cm2.
Beispiel 2: Es wurde wie im l.BeBpiel gearbeitet, jedoch wurden 2,6 Mol Formaldehyd eingesetzt, es wurde bis zu einer Erweichungstemperatur von ca. 1000C kondensiert, es wurde in einem Gemisch aus 09 und C10-Aromaten gelöst und mit einem Triäthylamin-Wasser-Aceton-Azeotrop begast. Der Mittelwert der Biegefestigkeit betrug bei den 6 Stäben, die unmittelbar nach dem Mischen hergestellt worden waren, 4-3,0 kp/cm2 und bei den 6 Stäben, die aus der 3 Stunden gelagerten Mischung hergestellt 2 worden waren, 36,7 kp/cm2.Example 2: It was worked as in the first example, but 2.6 Mol of formaldehyde used, it was up to a softening temperature from about 1000C condensed, it was dissolved in a mixture of 09 and C10 aromatics and gassed with a triethylamine-water-acetone azeotrope. The mean value of the flexural strength for the 6 bars that were made immediately after mixing, 4-3.0 kp / cm2 and for the 6 rods, those made from the mixture stored for 3 hours 2, 36.7 kgf / cm2.
Beispiel 3 (nicht erfindungsgemäß) Es wurde wie im 1. Beispiel gearbeitet, jedoch wurden statt der 70 g erfindungsgemäßen Ketonharzlösung 70 g einer 4-0 96-igen Lösung eines handelsüblichen Phenol-Formaldehyd-IXowLaks, an dem ein Nethylolgruppengehalt nachgewiesen werden konnte, in Cyclohexanon eingesetzt. Der Mittelwert der Biegefestigkeiten betrug bei den 6 Stäben, die unmittelbar nach dem Mischen hergestellt worden waren, 39,2 kp/cm2. Die Mischung war 40 min.Example 3 (not according to the invention) The procedure was as in the 1st example, however, instead of the 70 g ketone resin solution according to the invention, 70 g of a 4-0 96 solution were used Solution of a commercially available phenol-formaldehyde-IXowLak with a content of methylol groups could be detected, used in cyclohexanone. The mean value of the flexural strengths for the 6 bars that were made immediately after mixing, 39.2 kg / cm2. The mix was 40 min.
nach dem Mischen fest, so daß keine weiteren Stäbe hergestellt werden konnten.solid after mixing so that no more bars are made could.
Beispiel 4.Example 4.
Aus der Mischung des 1. Beispiels wurden vier Stunden nach dem Mischen Stäbe hergestellt und nicht katalytisch, sondern durch Lagern bei 1800C gehärte-t. Sie hatten eine mittlere Biegefestigkeit von 41 kp/cm2.The mixture of Example 1 became four hours after mixing Rods made and hardened not catalytically but by storage at 1800C-t. They had an average flexural strength of 41 kp / cm2.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19702039330 DE2039330C3 (en) | 1970-08-07 | Molding compound for polyurethane-bound foundry molded parts |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19702039330 DE2039330C3 (en) | 1970-08-07 | Molding compound for polyurethane-bound foundry molded parts |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DE2039330A1 true DE2039330A1 (en) | 1972-02-10 |
| DE2039330C3 DE2039330C3 (en) | 1977-08-11 |
Family
ID=
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2356703A1 (en) * | 1972-11-17 | 1974-06-06 | Ashland Oil Inc | BINDERS AND THEIR USE FOR THE MANUFACTURING OF FOUNDRY SHAPES AND CORES |
| DE102020118148A1 (en) | 2020-07-09 | 2022-01-13 | Bindur Gmbh | Molding material for the production of cores and process for its hardening |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2356703A1 (en) * | 1972-11-17 | 1974-06-06 | Ashland Oil Inc | BINDERS AND THEIR USE FOR THE MANUFACTURING OF FOUNDRY SHAPES AND CORES |
| DE102020118148A1 (en) | 2020-07-09 | 2022-01-13 | Bindur Gmbh | Molding material for the production of cores and process for its hardening |
| WO2022008001A1 (en) | 2020-07-09 | 2022-01-13 | Bindur Gmbh | Moulding material for producing cores and method for curing same |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C3 | Grant after two publication steps (3rd publication) | ||
| E77 | Valid patent as to the heymanns-index 1977 | ||
| 8339 | Ceased/non-payment of the annual fee |