TW202026071A - Process for producing a metallic casting or a cured shaped part using an aliphatic binder system - Google Patents

Abstract

A process (i) for producing a metallic casting and/or (ii) for producing a cured shaped part selected from the group consisting of casting mould, core and feeder for use in the casting of metallic castings and also a mould material mixture for use in this process are described. Furthermore, a description is given of the use of an aliphatic polymer comprising hydroxy groups which has been crosslinked by one or more aliphatic polyisocyanates as binder of a shaped part for use in the casting of metallic castings. A description is likewise given of a cured shaped part for use in the casting of metallic castings, including a shaped part having good green strength, and preferably able to be produced by the process of the invention. In addition, the use of biopolymers from the group consisting of poly-D-glucosamines as binder or binder component for producing a shaped part having good green strength in the foundry industry is described.

Description

Method for producing metal castings or hardened molded parts using aliphatic adhesive system

The present invention relates to a method (i) for producing metal castings and/or (ii) for producing hardened molded parts for casting metal castings, the hardened molded parts selected from the group consisting of molds, cores and replenishment ports Group, and especially the mold material mixture used in this method.

The present invention further relates to the use of aliphatic polymers that contain hydroxyl groups and have been cross-linked with one or more aliphatic polyisocyanates as binders for casting metal castings.

The present invention also relates to a hardened molded part for casting metal castings, which includes a molded part that has good strength in the green state and is preferably produced by the method of the present invention.

The present invention also relates to the use of biopolymers from the group consisting of poly-D-glucosamine, which are used as binders or binder components to produce good strength in the green state in the foundry industry The forming part.

The casting molding part used for metal castings (hereinafter also referred to as "molding part"), especially the core, mold and replenishment port (including replenishment port cover and replenishment port shell or replenishment port sheath), usually composed of refractory base mold material , The refractory base mold material contains (depending on the intended use) one or more refractory solids, such as silica sand, and/or one or more particulate lightweight fillers, such as spheres made of fly ash, and suitable adhesives, which After removing the molded part from a molding tool (for example, a molded part cassette such as a core cassette or a mold cassette, see below), sufficient mechanical strength of the molded part is provided. In the uncured state, the mixture of base mold material and adhesive (which may contain other additives as appropriate) is called "mold material mixture".

The refractory solid is preferably present in particulate and free-flowing form so that it can be introduced into a suitable hollow mold (molding tool, see above) after being incorporated into the mold material mixture and be densified there. For this purpose, the replenishment port and the nucleus are usually introduced into the mold under pressure (that is, "blowing") in the nuclear injection machine. Relatively small molded parts are usually blown as well, while larger molded parts, especially relatively large molds, are usually formed by punching in a die box. Generally speaking, all formed parts can also be produced by stamping in a suitable mold, such as in manual forming methods. In order to obtain a blowable or stampable mold material mixture, its moisture content must be appropriately set, especially in the case of water-based adhesives, so that the mold material mixture has sufficient size for the respective mold process Stability, or the ratio of the liquid component and the solid component of the mold material mixture must be appropriately set.

The molding parts such as molds, cores and replenishment ports must meet various typical requirements of foundries. The way and extent of meeting these requirements is basically determined by the adhesive used in its production.

After the molded part is generated, that is, immediately after the molded part has been removed from the production tool, the molded part should have extremely high strength. The strength at this point in time ("initial strength", also known as "green strength"; see also below) is particularly important for the safe handling of cores, molds, or replenishment ports from production tools.

High final strength (that is, the strength after the hardening of the molded part is completed) and high heat resistance of the molded part during actual metal casting are also important (especially for the core and mold), so that the molded part is not in the cast metal Deforms under weight (that is, maintains good dimensional stability during the casting operation, also known as "casting strength") and can produce metal castings that are better free of casting defects. In this case, it is also important that the molded part used has an extremely clean or smooth surface without deformation or the like. This is because otherwise, the surface defects of the molded part can be transferred to the surface generated by this method. The surface of the metal casting.

In addition, the high resistance of the molded part to water moisture is a great advantage. Generally speaking, this kind of high humidity resistance makes the storage time of the molded part relatively long, even under severe climatic conditions (hot and humid climate) and ideally for several days or weeks, which is helpful for production The forming part of the reserve and its storage may make it possible for the first time. In this way, the industrial manufacturing flexibility of metal castings using these molded parts is greatly increased. It has also been found that in the case of all the molded parts of the metal used for casting, especially in the case of the replenishment port, the water absorption rate (for example, by absorbing water from the air during its storage) can cause the Vapor bubbles are formed by the corresponding water inclusions, which can cause pits to form in the metal casting, making this unusable. In extreme cases, there may even be an explosion due to rapid water vapor formation. The high moisture resistance of the molded part is also advantageous because it allows for example the use of the molded part with different types of refractory coatings and especially also with water-based refractory coatings. The refractory coating is a ceramic-based mold release agent, which in some cases is intended to prevent direct contact between the molded part (such as the core) and the molten metal, so that the molded part can be better tolerated during metal casting High thermal stress.

Considering the high quality of metal castings, it is also necessary to extract very little heat energy from the molten metal in the molded part, for example by a reaction such as a binder that can occur in known melting reactions such as water glass binders. This type of heat extraction can cause the metal melt to solidify prematurely and therefore cause incomplete casting operations. This characterization of the adhesive in its ability to absorb heat energy itself is also called its "quenching behavior". Especially in the case of replenishment ports, especially good thermal insulation is needed or necessary in order to keep the molten metal liquid as long as possible during the metal casting and to achieve extremely low sinkhole formation in the metal casting, which allows any sinking The hole formation occurs at most outside the finished metal casting (for example, only in the replenishment port).

After the casting operation is completed, the molded part should then be decomposed preferably under the action of the heat released from the cast metal, in such a way that the molded part loses its mechanical strength, that is, the cohesion between the individual particles of the base mold material is lost. In an ideal situation, the molded part then disintegrates again to obtain fine particles of the base mold material that can be easily removed and have very few residues from metal casting. If the molded part is a core, such favorable disintegration characteristics result in particularly good core removal capabilities of the metal casting.

In this case, it is also particularly necessary for the decomposition of the molded part (which is generally related to the thermal decomposition of the adhesive) to occur in a better emission-free manner, that is, no unpleasant odor and/or even health-hazardous materials are emitted in order to maintain the The exposure or danger to the health of the workers in the casting is as small as possible, or reduce or ideally prevent such exposure or danger. Such damage caused by unpleasant odors and/or health-hazardous materials can especially occur during casting using hot metal melt. In this case, the replenishment port that usually protrudes from the mold is the main reason, but when the metal casting solidifies This is also the case when it is released from the mold ("unencapsulated" or "released").

Various organic and inorganic adhesives are known, all of which have typical limitations or shortcomings, and are used to produce molded parts for the foundry industry.

Among organic adhesives and adhesive systems, adhesives/adhesive systems that can be hardened by cold or thermal methods in each case are known.

In the case of the thermal hardening method, after molding, the mold material mixture is heated, for example, by means of a heated molding tool to a height high enough to drive off the solvent present in the adhesive and/or initiate a chemical reaction (by means of its hardening of the adhesive) temperature. An example of such a thermal hardening method is the "hot box method". Today it is mainly used in the mass production of nuclear.

The term cold hardening method is used to refer to a method that is carried out substantially without heating the molding tool used for nuclear production (generally at room temperature or at a temperature generated by any chemical reaction, for example). Hardening is achieved, for example, by means of a gas which is introduced into the mold material mixture to be hardened and triggers a suitable chemical reaction. An example of this type of cold hardening method is the "cold box method" widely used in the foundry industry today.

However, both the hot box method and the cold box method use an organic binder based on a phenol resin in the prior art. These substances have (regardless of their exact composition) the following disadvantages: When they are decomposed by the temperature common during metal casting as necessary, they sometimes release large amounts of pollutants such as benzene, toluene and xylene (also referred to as "BTX") . In addition, the use of such organic binders to cast metals generally causes undesirable odors and smoke or smoke emissions. In the case of some of these adhesive systems, undesired emissions even occur during the production and/or storage of the molded part.

As an alternative to the above-mentioned organic adhesives, there are known corresponding inorganic adhesives that do not exhibit the above-mentioned phenomenon of releasing undesired odors or pollutants during metal casting, or exhibit this phenomenon to a much smaller extent. An example of such an inorganic binder is water glass. The corresponding mold material mixture basically consists of a basic mold material, such as silica sand, and water glass (in the form of an aqueous solution of alkali metal silicate). The mold material mixture is hardened by, for example, exposure to CO ₂ gas.

However, the use of such inorganic adhesives is related to other typical disadvantages: therefore, the molded parts produced by inorganic adhesives usually only have lower strength. This is especially noticeable immediately after removing the molded part from the tool. In addition, the frequent low moisture resistance of these adhesives limits the storage capacity of the molded parts produced by them. In addition, inorganic adhesives generally do not exhibit satisfactory disintegration characteristics, so complex trimming of metal castings produced by such molding parts is required. It is also known that the water glass combined replenishment port generally has worse insulating properties than the replenishment port combined with an organic adhesive. Finally, inorganic binder systems such as water glass are themselves known to absorb, that is, consume a considerable amount of heat energy during metal casting, so the metal melt solidifies relatively early, making casting defects possible. This is especially suitable for the casting of iron and steel using the high casting temperature required here.

In the prior art, a variety of adhesives, including organic adhesives, and methods of using such adhesives to produce molded parts have been discussed: The document DE 10 2007 031376 A1 describes an alternative cold box method using crude oil.

The document DE 196 154 00 A1 describes the use of a polymer as a binder for the production of ceramic green bodies and a method for producing ceramic objects.

Document JPH 061 57860 A describes water-resistant compositions.

Document JPS 61 276813 A discloses hardenable compositions.

The document EP 677 346 A2 relates to a casting method using a synthetic resin core, a synthetic resin core and a cast workpiece.

Document WO 96/26231 A1 describes a chemical binder, isocyanate and catalyst containing ester-based polyols.

The document WO 2011/044003 A2 relates to lignite-urethane-based resins used for casting sand with improved performance.

The document WO 2017/071695 A1 describes a phenol-formaldehyde resin-free adhesive for casting mold sand.

The document WO 2017/093371 A1 describes a method for producing refractory composite particles and replenishment port elements for the foundry industry, corresponding replenishment port elements and uses.

However, in view of the prior art, there is still a need for methods for the production of metal castings or for the production of hardened molded parts for casting metal castings, which achieve one, more than one, and ideally all of the following advantageous properties: -The high initial strength of the molded part produced by the method is sufficient for practical use under any circumstances; -High final strength of the molded part produced by the method; -High casting resistance or heat resistance of the molded part produced by the method; -Clean and smooth surface of the molded part produced by the method; -The extremely high moisture resistance or extremely high water resistance method of the molded part produced by the method, so that especially the molded part has excellent or long storage capacity and/or these parts can be stored under various climatic conditions. Use with water-based refractory coating; -Very low heat absorption, and ideally, good thermal insulation of the formed part produced by the method during metal casting; -During the casting of light metals and their alloys, as well as in the casting of iron and steel, especially under the conditions of metal casting, odorous materials and/or pollutants and smoke or smoke from the forming part generated by the method Very low emissions; -At least part of the use of renewable starting materials; -Very low expenditure in terms of equipment for carrying out the method, especially (even) the ability to carry out the method without heating tools (that is, the ability to be at least similar to the known cold box production method and corresponding equipment) .

In addition, there is also a need for adhesives for the molding part of the casting of metal castings, which have or achieve one, more than one, and ideally all of the above-mentioned beneficial and related properties, and require a mixture of mold materials to Used in such methods. In addition, it is also necessary to have one, more than one, and ideally all the molding parts of the relevant characteristics mentioned in the above method. There is also a need for adhesives that make it possible to manufacture molded parts with good green strength for the foundry industry, especially in the sense of flexible configuration corresponding to the production method.

Therefore, the main object of the present invention is to provide a method for producing metal castings or for producing hardened molded parts for casting metal castings, which causes or has one, more than one, and ideally All and provide a mold material mixture especially used in the above method.

Another object of the present invention is to provide an adhesive for forming parts during casting of metal castings, which has or causes one, more than one, and ideally all of the above-mentioned advantageous and related properties.

The specific objective of the present invention is also to provide a hardened forming part for casting metal castings, which has one, more than one, and ideally all of the relevant characteristics mentioned in the above method.

In addition, an object of the present invention is to provide an adhesive, which also makes it possible to manufacture an adhesive with good green strength for the molded part (preferably at room temperature) used in the foundry industry.

It has been unexpectedly discovered that by the method of the present invention for i) the production of metal castings and/or ii) the production of hardened molding parts selected from the group consisting of molds, cores and replenishment ports for casting metal castings, To achieve the main objective and other objectives and/or sub-objectives of the invention, the method includes the following steps: V1) Production of a mold material mixture containing (or consisting of) the following ingredients: a) at least one base mold material, b) one Or a plurality of aliphatic polymers, which in each case contains a hydroxyl-containing structural unit of formula I -CH ₂ -CH(OH)- (I), c) as a curing agent component, one or two selected from the following The components of the group: c1) one or more biopolymers selected from the group consisting of poly-D-glucosamine and c2) one or more preferably water-dispersible crosslinking agents for the hydroxyl groups of one or more aliphatic polymers And/or aliphatic polyisocyanates; and d) water; V2) molding the molding material mixture, and subsequently V3) hardening the molding material mixture or unhardened downstream products formed therefrom in one or more steps, thereby Produce hardened molded parts.

The present invention and the preferred parameters, characteristics and/or preferred combinations of the components of the present invention are defined in the scope of the attached patent application. The preferred aspects of the present invention are also indicated or defined in the following description and examples.

The method of the present invention (including its variants and preferred variants) makes it possible to produce hardened molded parts for the foundry industry, especially molds, cores and replenishment ports (insulation replenishment ports and heat-generating replenishment ports, including replenishment cover and replenishment ports) Sheath), these hardened molded parts have many advantageous properties. Depending on the configuration of the method (or its variants or preferred variants), one, more than one, or all of the aforementioned advantageous characteristics can be achieved. All variants and embodiments of the method of the present invention generally only exhibit less emission of odorous materials and/or pollutants and smoke or fumes. In a preferred embodiment of the method of the present invention, even only odorous materials and/or pollutants and very little emission of smoke or smoke occur. In addition, the formed part produced by all the variants and embodiments of the method of the present invention hardly tends to absorb thermal energy and exhibit favorable quenching behavior, which is common for all the variants and embodiments of the method of the present invention.

In the method of the present invention shown above, the mold material mixture is preferably produced by thoroughly mixing components a) to d) with each other in step V1) so as to obtain an extremely uniform distribution in the mold material mixture. The mixing of the components with one another is carried out in a manner known per se, for example using a stirrer suitable for this purpose, such as a wing stirrer. For preferred embodiments of ingredients a) to c), see below.

In step V2), the mold material mixture is shaped to obtain a three-dimensional structure selected from the group consisting of a mold, a core, and a replenishment port (including a replenishment port cover and a replenishment port sheath). Step V2) is preferably performed in a molding tool.

For the purpose of the present invention, the term "molding tool" refers to a molding part that can be used in the foundry industry to form a mold, core, and replenishment port (including replenishment port cover and replenishment port sheath). Any of the tools, especially the forming part of the box (including the die box and the core box) and the blow molding machine used for the blow molding part, especially the core shooter.

If the molding in step V2) is performed in a blow molding machine, for this purpose, it is preferable to set the ratio of the total moisture content to the total solid content in the molding material mixture before or during the molding of the molding material mixture, so that the molding material mixture It can be blown in a blowing machine, or can be punched in the forming part of the box. This setting can be easily performed by a person familiar with the technology.

Step V3) of the method of the present invention shown above includes hardening the molding material mixture or the unhardened downstream product formed therefrom to produce a hardened molded part. At least the dimensionally stable hardened molded part is preferably produced by the hardening in step V3). In this context, "dimensionally stable" means that the molded part with this characteristic retains its shape, so that, for example, even after the molding tool is removed, it can be handled at least without losing or damaging its shape, and for example At the production site, it is transported to the subsequent further processing station.

In the context of the present invention, the hardening in step V3) of the molding material mixture or the unhardened downstream product formed therefrom includes one, two, or all three steps selected from the group consisting of (in each case , Within the scope that can be used in specific variants or embodiments of the method of the present invention): V31) Precipitating at least a part of one or more biopolymers (in the molding material mixture and/or the unhardened downstream product formed therefrom) to produce a molded part with good green strength (for other details, see Below), V32) By heating and/or removing water to treat the molding material mixture and/or the unhardened downstream products formed therefrom and/or (if step V31 has been performed in advance)) the molded part with good green strength ( For other details, see below), and V33) In the molding material mixture and/or in the uncured downstream products formed from it and/or in the molded part with good green strength (if step V31 has been performed in advance), by means of polyisocyanate ( Component c1), if present), preferably water-dispersible and/or isocyanate groups of aliphatic polyisocyanates, crosslink one or more hydroxyl groups of aliphatic polymers of formula I (component b)), This produces a cross-linked molded part as a hardened molded part (for other details, see below).

For the purpose of the present invention and consistent with the common understanding in the technical field, the term "has good green strength" means "dimensionally stable or hardened or pre-hardened, so as to have a stable shape, but has not been tested for the actual intended purpose. Enough hardened (cured) or fully cured (hardened)". The molded part with good green strength has sufficient hardness for removal from a molding tool or transfer to subsequent processing steps, but usually does not have sufficient hardness for the actual intended purpose, where it is used to produce metal castings. For example, when the method is performed in the absence of a heatable molding tool, it is better to produce a molded part with good green strength in the method of the present invention: a molded part with good green strength It can then be further processed with the moulding tool used to produce it or in the absence of the moulding tool, especially according to step V32) and/or step V33) of the method of the invention, for example in a conventional drying oven. In order to produce a molded part with good green strength in step V3) or V31), according to the method of the present invention, component c1) in the molding material mixture, one or more selected from the group consisting of poly-D-glucosamine The presence of biopolymers is required. For the purpose of the present invention, the molded part with good green strength obtained after step V31) means the hardened molded part.

In a preferred embodiment of the method of the present invention, where the hardening in step V3) covers step V31), at least a part of one or more biopolymers (preferably polyglucosamine, see below) used in the method, preferably The total amount is precipitated from the aqueous part of the molding material mixture or the unhardened downstream product formed therefrom. This is preferably achieved by increasing the pH of these aqueous parts in a manner known per se. Raising the pH can be done in any known way, for example by adding an aqueous base. The pH value of the aqueous part of the molding material mixture or the unhardened downstream product formed therefrom is preferably by using one or more alkaline compounds that are gaseous under the reaction conditions, preferably one or more that are gaseous under the reaction conditions The amine treatment to improve. Preferably, one gaseous amine or one of a plurality of gaseous amines is N,N'-dimethylpropylamine. Due to the increased pH in the molding material mixture or the unhardened downstream product formed therefrom, in each case, the molding material mixture or the unhardened downstream product formed therefrom contains one or more types of poly-D- Glucosamine (preferably polyglucosamine) is a group of biopolymers. At least a part of these biopolymers precipitates from the aqueous component of the molding material mixture or the unhardened downstream product formed therefrom, thereby producing a good The forming part of green strength. The production of molded parts with good green strength by the method of the present invention can be performed in a manner known per se, especially according to the step of hardening or curing the molding material mixture (or the unhardened downstream product formed by it) in the cold box method: It is not necessary to increase the temperature (heating) to produce a molded part with good green strength by the method of the present invention, so this step can be carried out, for example, in a cold box tool known per se. For example, a cold box nuclear machine without a heating device is suitable for this purpose, and there is no need to make considerable changes to it for this purpose. This is because, for example, the hardened molding material mixture (or the unhardened downstream product formed by it) The steps are also carried out in the cold box method, preferably by treatment with gaseous amines. The mold, core and replenishment port with good green strength can be produced in the above-mentioned manner by the method of the present invention.

Preferably according to step V32) further process the molding material mixture (as obtained after step V2)) and/or unhardened downstream products formed therefrom and/or molded parts with good green strength (as in step V31) Obtained later) (see below). After step V32) has been performed, the molded part produced by the method of the present invention usually has sufficient hardness for producing metal castings. The processing in step V3) or V32) is by heating the molding material mixture and/or the unhardened downstream product formed therefrom and/or the molded part with good green strength, and/or by the self-molding material mixture, Downstream products or molded parts with good green strength (as indicated above) are achieved by pumping water, as described in more detail below.

If possible (ie if ingredient c2), one or more polyisocyanates (as defined above or below or as preferred) as crosslinking agents for the hydroxyl groups of one or more aliphatic polymers are present in step V1) If necessary, the (hardened) molded part obtained after step V31) and/or after step V32) is further reacted in step V33) by allowing one or more aliphatic polymerization of formula I The hydroxyl group of the material is cross-linked by the isocyanate group of the above-mentioned polyisocyanate to obtain a cross-linked (hardened) molded part. According to the method of the present invention, component c2) is the presence of one or more polyisocyanates (as defined above or below or as preferred) as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers in the molding material mixture It is necessary to generate a cross-linked molded part in step V3) or V33).

In step V33), the cross-linking of the hydroxyl group and the isocyanate group is preferably carried out by heating the molding material mixture and/or the uncured downstream product formed therefrom and/or the molded part with good green strength, and preferably At the same time, water is extracted from it so that at least partial cross-linking of hydroxyl and isocyanate groups (step V33)) occurs when step V32) is properly carried out and component c2) is present in the mold material mixture. In a variant of the method of the present invention in which step V3) covers both steps V32) and step V33), for the purpose of the present invention, it means that the crosslinked (hardened) molded part of the hardened molded part is used as the method of the present invention The product or final product produced. See below for more details.

The cross-linked (hardened) molded part (as obtained after both step V32) and step V33) have been performed generally has sufficient hardness for the production of metal castings, and additionally preferably has favorable high moisture resistance or high water resistance . In each case, the initial strength, final strength and casting strength of such crosslinked (hardened) molded parts are generally particularly high.

Preferably the method of the invention as indicated above, preferably the method (ii) according to the invention (preferably as mentioned above or below as the preferred method of the invention), wherein -The mold material mixture contains (at least) component c1) as the curing agent component c), one or more biopolymers selected from the group consisting of poly-D-glucosamine, And preferably (additionally) it contains ingredient c2), one or more polyisocyanates (as defined or defined as preferred above or below), preferably (one or more) aliphatic polyisocyanates, as one or more aliphatic polymers Cross-linking agent for the hydroxyl of the substance, And/or (preferably "and") -Hardening coverage in step V3) V31) Precipitating at least a part of one or more biopolymers (in the presence of component c1), Preferably by increasing the pH value of the aqueous part of the molding material mixture, especially by contacting with a basic gaseous compound, preferably by treating with a basic gaseous compound gas, very preferably by treating with a gaseous amine, So as to produce a molded part with good green strength; And/or (preferably "and") V32) Process the molding material mixture and/or the unhardened downstream products formed therefrom and/or (if step V31 has been performed in advance)) the molded part with good green strength, -By heating the molding material mixture and/or the unhardened downstream product formed therefrom and/or the molded part with good green strength to preferably within the range of 100°C to 300°C, especially preferably Temperature in the range of 150°C to 250°C and excellently in the range of 180°C to 230°C, And/or (preferably "and") -By removing water from the molding material mixture and/or unhardened downstream products formed free of it and/or removing water from the molded parts with good green strength.

In many cases, it is also preferable to use the embodiment of the method of the present invention indicated above, in which the mold material mixture contains only component c1) as the curing agent component c), one or more selected from poly-D-glucose The biopolymers of the group consisting of sugar amines (that is, in this embodiment, the curing agent component c) does not contain the component c2), one or more polyisocyanates). In this embodiment of the method of the present invention (which is preferred in many cases), step V31) is preferably carried out to precipitate at least a part of one or more biopolymers for forming a mold with good green strength Part. In this embodiment of the method of the present invention, step V32) preferably uses a molding material mixture (such as obtained after step V2), and then does not perform step V31)) in advance, or preferably uses a molded part with good green strength (For example, after step V31), except for performing step V31) before and after performing step V31) before).

Step V32) Removal of middle water (in all variants of the method of the present invention covering step V32) and removal of water) is carried out by means of one, two or all three measures selected from the group consisting of: -Freeze-dried molding material mixture and/or unhardened downstream products formed therefrom and/or molded parts with good green strength, -Vacuum drying the molding material mixture and/or the unhardened downstream products formed therefrom and/or the molding parts with good green strength, and -Heat the molding material mixture and/or the unhardened downstream product formed therefrom and/or the molding part with good green strength (and remove the water from the molding material mixture and/or the unhardened downstream product formed by it And/or remove water from the formed part with good green strength).

Step V32) Removal of water (in all variants of the method of the present invention covering step V32) and removal of water) is preferably by heating the molding material mixture and/or the unhardened downstream product formed therefrom and /Or a molded part with good green strength, and (preferably at the same time) remove water from the molding material mixture and/or unhardened downstream products formed from it and/or from a molded part with good green strength Remove the water to proceed.

Also preferred are the embodiments of the method of the invention indicated above, preferably the method (ii) according to the invention (preferably the above or below indicated as the preferred method according to the invention), wherein the mold material mixture Contains only component c1) as the curing agent component c), one or more biopolymers selected from the group consisting of poly-D-glucosamine, and the method is in addition to step V31) defined above and above The step V31) defined in the text includes the following steps: V32) Processing the molded part with good green strength -By heating the molded part with good green strength to preferably in the range of 100°C to 300°C, particularly preferably in the range of 150°C to 250°C and extremely preferably in the range of 180°C to 230°C Internal temperature, And/or (preferably "and") -By removing water from the molded part with good green strength.

In another particularly preferred embodiment of the method of the present invention, the mold material mixture contains as the curing agent component c) component c1), one or more biopolymers selected from the group consisting of poly-D-glucosamine, And additionally component c2), one or more polyisocyanates (as defined above or below or defined as preferred). In this embodiment, it is possible to produce shaped parts with particularly advantageous properties, especially shaped parts with especially high moisture resistance or especially high water resistance, especially high initial strength, especially high final strength and especially high casting resistance. .

In a particularly preferred embodiment of the above-described method of the present invention in which the mold material mixture contains component c) as the curing agent component c) and additionally component c2), the polyisocyanate of component c2) is preferably selected from the group consisting of : -Aromatic polyisocyanate, preferably water-compatible aromatic polyisocyanate, especially preferably water-dispersible aromatic polyisocyanate, -Aliphatic polyisocyanates, preferably water-dispersible aliphatic polyisocyanates, especially preferred aliphatic polyisocyanates described in more detail below, and -Its mixture.

The particularly preferred curing agent component c2) in the method of the invention described above or below (or in the preferred method of the invention described above or below) is (if curing agent component c2 is used or present)) The water-dispersible polyisocyanate is preferably selected from the group consisting of: water-dispersible aromatic polyisocyanate, water-dispersible aliphatic polyisocyanate and mixtures thereof. The excellent curing agent component c2) in the method of the invention described above or below (or in the preferred method of the invention described above or below) is (if curing agent component c2 is used or present)) water Dispersible aliphatic polyisocyanate.

Water-dispersible polyisocyanates themselves are known in the technical field, especially from WO 2011/144644 A1 or from the product manual "The Chemistry of Polyurethane Coatings", Bayer MaterialScience LLC (08 /05) Known. Its outstanding feature is that it can act as a crosslinking agent even in aqueous or aqueous media, especially as a crosslinking agent for non-aqueous hydroxyl groups (such as alcoholic hydroxyl groups). In contrast, according to the prior art in the foundry industry, for example, aromatic polyisocyanates used as cold box adhesives cannot be used in aqueous or aqueous media in the desired manner. However, in each case, they contain hydroxyl-containing structures. The combination of aliphatic polymers (especially polyvinyl alcohol) of the units is advantageous or even necessary because of the high reactivity of its isocyanate functional groups.

In the method of the present invention described above or below (or in the preferred method of the present invention described above or below) as the curing agent component c2) (if the curing agent component c2 is used or present)) is particularly preferred. The water-dispersible polyisocyanates used are those that meet the selection criteria indicated below: Within 24 hours, the water-dispersible polyisocyanate forms a fluid under contact with water, and there are no solid particles that can be distinguished by the naked eye without the presence of optical aids. In order to verify whether the polyisocyanate is water-dispersible, 100 mg of polyisocyanate (preferably in the form of a 100 µm thick film) is introduced into 100 ml of water (at 20°C) and shaken on a commercial shaking table for 24 hours. When the solid particles are no longer discernible after shaking, but the fluid has turbidity (which can be discerned by the naked eye in the absence of optical aids), the polymer is water-dispersible.

Aromatic polyisocyanates (as indicated above) have the following advantages: they can be crosslinked with one or more aliphatic polymers containing hydroxyl-containing structural units of formula I and are therefore very suitable for producing molded parts with high moisture resistance . However, when it is important to work in the foundry industry where emissions are extremely low and produce very few odorous materials and/or pollutants, the use of aromatic polyisocyanates is particularly unfavorable because of When aromatic polyisocyanates are used, such undesired emissions occur to an increased degree. For the purpose of the present invention, the term "aromatic polyisocyanate" refers to a polyisocyanate containing an organic aromatic ring (that is, an aromatic hydrocarbon as a structural component).

In all variants of the process of the invention in which component c2) is used in step V1), the polyisocyanate of component c2) therefore preferably comprises an aliphatic polyisocyanate, particularly preferably a water-dispersible aliphatic polyisocyanate and very preferably below. The preferred aliphatic polyisocyanates are described in detail. Compared to aromatic polyisocyanates, aliphatic polyisocyanates are significantly better for use in aqueous or aqueous media because of their reduced reactivity compared to aromatic polyisocyanates. The above-mentioned aliphatic polyisocyanate, water-dispersible aliphatic polyisocyanate or preferably aliphatic polyisocyanate (defined below) preferably constitutes these preferred variants of the method of the present invention (wherein component c2) is used in step V1)) The proportion of the total mass of one or more polyisocyanates used (or present) in the mold material mixture is ≥75% by weight, particularly preferably ≥90% by weight and extremely preferably ≥95% by weight. In a particularly preferred variant of this embodiment of the method of the invention, the polyisocyanate of component c2) is only (that is, 100% by weight based on the total mass of one or more polyisocyanates used or present in the molding material mixture) Contains aliphatic polyisocyanates, preferably contains only water-dispersible aliphatic polyisocyanates, and particularly preferably contains only the preferred aliphatic polyisocyanates described in more detail below.

Aliphatic polyisocyanates have the following advantages: Compared with, for example, aromatic polyisocyanates (that is, organic polyisocyanates containing aromatic rings), when the method of the present invention is carried out, it causes undesirable odorous materials and/ Or the emission of pollutants and smoke or smoke.

Therefore, the method of the present invention as indicated above is also preferred, and the method (ii) according to the present invention is preferred (preferably the above or below indicates the preferred method of the present invention), among them -The component c2 of the mold material mixture (if used or present) contains one or more water-dispersible polyisocyanates or consists of one or more water-dispersible polyisocyanates, or -(If used or present, component c2)) one or more polyisocyanates include one or more water-dispersible polyisocyanates or (if used or present, component c2)) one or more polyisocyanates are one or more water-dispersible Polyisocyanate.

In a particularly preferred embodiment of the method of the present invention in which the mold material mixture contains the component c1) as the curing agent component c) and additionally the component c2), step V31) is preferably carried out to precipitate one or more biopolymers At least a part is used to produce a molded part with good green strength.

If step V32) is carried out in this embodiment of the method of the present invention, it is carried out using a molding material mixture and/or an unhardened downstream product formed therefrom (as obtained after step V2), or otherwise Except for step V31), this step is preferably carried out using a molded part with good green strength. The removal of water in step V32) can be carried out by means of one, two or all of the above measures (freeze drying, vacuum drying, heating).

In a particularly preferred embodiment of the method of the present invention in which the mold material mixture contains component c) as the curing agent component c) and additionally component c2), it is preferable to perform step V33) in addition to step V32) (and more Good at the same time). The cross-linking of the hydroxyl group and the isocyanate group in step V33) for generating the cross-linked molded part preferably includes: -Heat the molding material mixture and/or the unhardened downstream products formed therefrom and/or the molded part with good green strength, preferably the molded part with good green strength, heated to preferably at 100°C To 300°C, especially preferably 150°C to 250°C and extremely preferably 180°C to 230°C, and -Remove water from the molding material mixture and/or unhardened downstream products formed by it and/or remove water from the molded part with good green strength, preferably from the molded part with good green strength In addition to water.

In this case, the hardening in step V3) of the method of the present invention therefore covers not only step V32) but also step V33) (as defined above).

As indicated above, the molding material mixture produced by the method of the present invention and/or the unhardened downstream products formed therefrom can be converted into hardened molding in the same way as the molded part with good green strength produced by the method of the present invention Part or cross-linked (hardened) molded part. That is, in the method of the present invention, step V32) can be performed after step V2) or after step V31). However, on the contrary, it is not preferable to perform step V31) after step V32), because after heating the molding material mixture and/or unhardened downstream products formed therefrom or after removing water therefrom, precipitation ( In step V31)) at least a part of one or more biopolymers in the molding material mixture and/or unhardened downstream products formed therefrom is generally not technically feasible or impossible.

In a variant of the method of the present invention, the heating of the molding material mixture (produced in step V2) and/or the unhardened downstream product formed therefrom is generally related to the molding tool (such as a molded part cassette or a blowing head) ) Together, in a drying device (such as a drying oven, belt dryer, through dryer, tunnel dryer or drying belt), or in addition, by passing heated gas, preferably heated air, through the molding Mold material mixture to reach the temperature indicated above, and preferably, particularly preferably, at the same time, remove water from the mold material mixture and/or unhardened downstream products formed free of it in order to proceed to step V32) (and Preferably, step V33)) is performed additionally or simultaneously. A drying oven, particularly preferably a convection drying oven, is preferably used as a drying device in this method variant. The hardened molded part (if present or still present) can then usually be removed from the molding tool.

In another variant of the method of the present invention, heating the molded part with good green strength, which has been produced by the method of the invention, is used together with the molding tool (such as the molded part cassette or the blowing head) or preferably without In the presence of a molding tool, in a drying device (such as a drying oven, a belt dryer, a through dryer, a tunnel dryer, or a drying belt) to reach the temperature indicated above, and preferably, and Particularly preferably, at the same time, water is removed from the molded part with good green strength in order to proceed to step V32) (and preferably to proceed to step V33) in addition or at the same time). In this method variant, a drying oven, particularly preferably a convection drying oven, is also preferably used as the drying device.

The advantage of this recently mentioned method variant is in particular: the molded part with good green strength does not necessarily have to be in the molding tool, and especially does not transform into a hardened molded part (especially cross-linked) in a heatable molding tool The hardened molded part), which can instead be taken out of the molding tool (for example at room temperature) and can be separately transformed in a suitable drying device (especially by heating and removing water as indicated above) into a hardened molded part Part (especially the cross-linked part). This makes it possible to use non-heatable moulding tools, such as the known cold box core shooter, for shaping the moulding material mixture or unhardened downstream products formed from it and/or for producing good green embryos The strength of the molded part makes it possible, for example, to carry out this method variant according to the invention without the need for complex and expensive reassembly of the production site for the cold box method. However, since carrying out this method variant is not limited to carrying out this method variant in a non-heatable moulding tool, it can be carried out at a production site equipped with different devices, making it possible to use the present invention in the industry with great flexibility Further advantages of the method.

Generally speaking, in step V32) and/or in step V33) the precise method parameters of the method of the present invention (such as the duration of heating, the temperature of the drying oven or the heating gas, the time for the passage of the heating gas (that is, the passage of the heating gas) The setting of the duration) and the pressure of the heating gas (if used) greatly depend on the characteristics of the molded part to be produced by hardening, such as its size, its weight, its volume or its wall thickness. When necessary, suitable parameters in a specific situation can be determined by a person familiar with the technology in a preliminary test in a manner known per se.

In addition, the method of the present invention as indicated above is preferred, and the method (ii) of the present invention is preferred (preferably the above or below indicates the preferred method according to the present invention), among them -The mold material mixture contains (at least) component c2) as the curing agent component c), one or more polyisocyanates (as defined above or below or as preferred), preferably (one or more) aliphatic poly Isocyanate, And preferably additionally includes component c1), one or more biopolymers selected from the group consisting of poly-D-glucosamine, And/or -The hardening in step V3) covers at least V32) Treat the molding material mixture and/or the unhardened downstream products formed therefrom and/or (in the presence of component c1) and before proceeding to step V31)) the molded part with good green strength, -By heating the molding material mixture and/or the unhardened downstream product formed therefrom and/or the molded part with good green strength to preferably within the range of 100°C to 300°C, particularly preferably Temperature in the range of 150°C to 250°C and excellently in the range of 180°C to 230°C, And/or (preferably "and") -By removing water from the molding material mixture and/or unhardened downstream products formed free of it and/or removing water from the molded part with good green strength, And (except for step V31) and/or V32), preferably except for step V32)) V33) In the molding material mixture and/or the uncured downstream product formed therefrom and/or the molding part with good green strength, make one or more hydroxyl groups of the aliphatic polymer of formula I and polyisocyanate (as above Or the isocyanate group crosslinking as defined below or as preferred), Thereby, a cross-linked molded part is produced as a hardened molded part.

In many cases, it is also preferable to use the embodiment of the preferred method of the present invention as indicated above, wherein the mold material mixture contains only the curing agent component c2) as the curing agent component c), one or more polyisocyanates (As defined or defined above or below is preferred) (that is, in this embodiment, the curing agent component c) does not contain ingredient c1), one or more selected from the group consisting of poly-D-glucosamine Biopolymers).

In this embodiment of the method of the present invention, the mold material mixture contains only the component c2) as the curing agent component c) (but not the component c1)), and the component c2) used (or present) in the mold material mixture Based on the total mass of one or more polyisocyanates, the polyisocyanate of component c2) preferably contains ≥75% by weight, particularly preferably ≥90% by weight and very preferably ≥95% by weight of aliphatic polyisocyanate, preferably water Dispersible aliphatic polyisocyanates and particularly preferred aliphatic polyisocyanates (indicated above and defined in more detail below), which are preferably used according to the invention. In a particularly preferred variant of this embodiment of the method of the invention, the polyisocyanate of component c2) contains only aliphatic polyisocyanates, preferably only water-dispersible aliphatic polyisocyanates, and especially preferably only contains the following more detailed The preferred aliphatic polyisocyanate is described as component c2). In this preferred embodiment of the method of the present invention (in which the mold material mixture contains only component c2) as the curing agent component c), no molded part with good green strength is produced.

In a preferred embodiment of the method of the present invention, wherein the mold material mixture contains only component c2) as the curing agent component c) (but not component c1)), step V32) and preferably additionally (and preferably with Step V32) Simultaneously) Step V33) is carried out in a manner similar to or corresponding to the above-indicated procedure, the above-indicated procedure relates to where the mold material mixture contains the component c1) as the curing agent component c) and the amount Example of the method of foreign ingredient c2). Here, step V32) is performed in each case using a molding material mixture (as obtained after step V2)) or an unhardened downstream product formed therefrom (but not using a molded part with good green strength).

Regarding a particularly preferred embodiment of the method of the present invention, wherein the mold material mixture comprises component c2) as the curing agent component c), one or more polyisocyanates (as defined above or below or as preferred), and External component c1), one or more biopolymers selected from the group consisting of poly-D-glucosamine, see above.

Therefore, it is preferable to use the method of the present invention for i) the production of metal castings and/or ii) the production of hardened molding parts selected from the group consisting of molds, cores and replenishment ports for i) production of metal castings as indicated above (more The above or below indicates a preferred method according to the present invention), which comprises the following steps: V1) Production of a mold material mixture comprising: a) at least one base mold material, b) one or more aliphatic polymers , Which contains the structural unit of formula I -CH ₂ -CH(OH)- (I) containing a hydroxyl group, c) as a curing agent component, and two components selected from the group consisting of: c1) one or more selected from poly -D-glucosamine group of biopolymers and c2) one or more polyisocyanates as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers (as defined above or below or preferably defined) , Preferably aliphatic polyisocyanate, particularly preferably water-dispersible aliphatic polyisocyanate, and d) water; V2) molding the molding material mixture, and subsequently V3) hardening the molding material mixture or the uncured downstream formed therefrom Product, wherein the hardening in step V3) comprises V31) precipitating at least a part of one or more biopolymers, preferably by increasing the pH value of the aqueous part of the molding material mixture, especially by contacting with a basic gaseous compound , Preferably treated with alkaline gaseous compound gas, excellently treated with gaseous amine, to produce a molded part with good green strength; and/or (preferably "and") V32) process the molding material mixture and / Or the unhardened downstream product formed therefrom and/or the processed part with good green strength, preferably the processed part with good green strength (after step V31 has been previously performed),-by Heat the molding material mixture and/or the unhardened downstream products formed therefrom and/or heat the molded part with good green strength (preferably the molded part with good green strength), and heat to preferably 100 ℃ to 300 ℃, especially preferably 150 ℃ to 250 ℃ and extremely preferably in the range of 180 ℃ to 230 ℃ temperature, and/or (preferably "and")-by self-forming mold The material mixture and/or the unhardened downstream product formed by it removes water and/or removes water from the formed part with good green strength (preferably removes water from the formed part with good green strength), And (except for step V31) and/or V32), preferably except for step V32)) preferably V33) in the molding die material mixture and/or unhardened downstream products formed therefrom and/or with good green strength In the molding part (preferably in the molding part with good green strength), one or more of the hydroxyl groups of the aliphatic polymer of formula I are cross-linked with the isocyanate groups of the polyisocyanate (used) to produce a hardened molding part Part of the cross-linked molding part.

In our own experiments, we have found that by the particularly preferred variant of the method of the present invention indicated above (that is, by wherein the mold material mixture includes components c1) and c2) and step V32) includes heating and moving The (crosslinked) hardened molded part produced by the method of the present invention in which water is removed and both steps V32) and V33) are carried out has high initial strength, especially high final strength (after hardening or crosslinking) and Especially high casting resistance and especially high heat resistance even during casting of iron or steel. The advantageous smooth and clean surface structure of these (crosslinked) hardened molded parts produced by the particularly preferred variant of the method of the invention indicated above is also outstanding. In addition, it can also be shown that the (cross-linked) hardened molded part produced by this particularly preferred variant of the method of the present invention indicated above has particularly good moisture resistance and water resistance, so it is significantly suitable for long-term Store for several days or weeks, even under difficult weather conditions (hot and humid climate). In metal casting, the (cross-linked) hardened molded part produced by this particularly preferred variant of the method of the invention indicated above additionally exhibits only low heat absorption, which causes very little pit formation, which also It only appears in the metal casting area that is relatively far away from the actual metal casting (for example, in the replenishment port connection part). This characteristic makes this variant of the method of the invention particularly suitable for the production of replenishment ports, especially insulating replenishment ports. After the metal casting is completed, the (cross-linked) hardened molded part produced by this variant of the method of the invention in particular also exhibits very favorable unencapsulation behavior, because most of it collapses due to the heat released during the metal casting Therefore, the further processing of the metal casting produced in this way is significantly simplified, because only a small amount or ideally no finishing steps are required on the produced metal casting.

The particular advantage of the forming part produced by the method of the present invention is its emission behavior, especially during metal casting and in the unencapsulation of metal castings that have been produced by means of these forming parts produced according to the present invention: therefore, in light metal In the casting of or its alloys (for example, in the casting of aluminum) and also in the casting of iron or steel or the unwrapping of metal castings produced in this way, almost no smoke or smoke is formed, and there is almost no bad smell And/or there is almost no discharge of materials, which are potentially harmful to health. They usually use conventional organic casting adhesives, especially organic casting adhesives containing aromatics (such as especially aromatic polyols and aromatic polyols). Isocyanate). This is particularly applicable to the replenishment port produced by the method of the present invention. The insulation supply port produced by the method of the present invention (especially by its preferred variants) hardly exhibits unwanted emissions even at the relatively low temperature of light metal casting. The heat supply port generated by the method of the present invention hardly exhibits undesired emissions (such as smoke) even during or after burning-off. When an aliphatic polyisocyanate, preferably indicated herein as a preferred aliphatic polyisocyanate, is used primarily or exclusively as component c2) in the method of the invention, and/or when used in the method of the invention to how much In the absence of other aromatic components, particularly low smoke or smoke formation, particularly low occurrence of unpleasant odors and/or particularly low emissions of potentially harmful materials are observed when there are no other aromatic-containing ingredients.

Also preferred is the method of the present invention as indicated above, preferably the method according to the present invention (ii) (preferably the above or below indicates the preferred method according to the present invention), The aliphatic polymer containing the structural unit of formula I containing the hydroxyl group used therein -Can be produced by at least partial hydrolysis of polyvinyl acetate; And/or -Choose from the group consisting of: polyvinyl alcohol, polyvinyl acetate and their mixtures; And/or -Except for one or more biopolymers selected from the group consisting of poly-D-glucosamine as used in the mold material mixture, the total mass of all organic polymers containing hydroxyl groups used ≥75% by weight, preferably ≥90% by weight, particularly preferably ≥98% by weight; And/or -Contains one or more polyvinyl alcohols, Among them, all the polyvinyl alcohols used are better -Preferably measured by the method indicated in paragraphs [0029] to [0034] of the document DE 10 2007 026 166 A1, the degree of hydrolysis is> 50 mol% (that is, in the range of 50.1 mol% to 100 mol%) , And it is better to measure by the method of DIN EN ISO 15023-02 2017-02 draft Annex D, especially preferably the degree of hydrolysis is in the range of 70 mol% to 100 mol%, and very preferably in the range of 80 mol% to 100 mol% Within %, And/or -Measured in accordance with DIN 53015:2001-02 in an aqueous solution of 4% strength (w/w) of all polyvinyl alcohol used at 20°C in each case. The dynamic viscosity is in the range of 0.1 to 30 mPažs, preferably In the range of 1.0 to 15 mPažs, particularly preferably in the range of 2.0 to 10 mPažs; And/or -≥75% by weight, preferably ≥90% by weight, particularly preferably ≥98% by weight of the total mass of all aliphatic polymers containing hydroxyl-containing structural units of formula I used in the mold material mixture.

In a preferred embodiment of the method of the present invention, all (that is, to the extent of 100% by weight) aliphatic polymers containing hydroxyl-containing structural units of formula I to be used are in the form of one or more polyvinyl alcohols .

The molding material mixture produced in step V1) of the method of the present invention contains component b) as an organic polymer containing hydroxyl, one or more aliphatic polymers containing hydroxyl-containing structural units of formula I, and (if present or used ) c1), one or more biopolymers selected from the group consisting of poly-D-glucosamine. In the method of the present invention, components b) and (if present or used) c1) constitute the total of all organic hydroxyl-containing organic compounds used in the mold material mixture in the mold material mixture produced in step V1) The mass is preferably ≥95% by weight, particularly preferably ≥98% by weight. In one of the particularly preferred variants of the method of the invention, the components b) and (if present or used) c1) constitute an organic hydroxyl group in the mold material mixture to be used in the mold material mixture produced in step V1) 100% by weight of the total mass of all organic compounds.

According to the present invention, it is preferable to produce one or more aliphatic polymers (component b)) containing hydroxyl-containing structural units of formula I, and to use these polymers in the form of aqueous mixtures in the production of the mold material mixture in step V1) (At least partly and preferably all), the aqueous mixture contains one or more aliphatic polymers of formula I structural units containing hydroxyl groups. Based on the total mass of the aqueous mixture containing one or more aliphatic polymers, the aqueous mixture preferably contains a total amount (concentration) in the range of 10% to 40% by weight, particularly preferably 15% to 35% by weight One or more aliphatic polymers within the range and extremely preferably within the range of 20% to 30% by weight.

Preferably, based on the total mass of the one or more aliphatic polymers used, ≥90% by weight, preferably ≥95% by weight, of the one or more aliphatic polymers used containing the structural unit of formula I containing hydroxyl groups Preferably, one or more polyvinyl alcohols are present in the aqueous mixture in a dissolved form.

It has been found that one or more aliphatic polymers indicated above, especially one or more polyvinyl alcohols indicated above as preferred, make an important contribution to the advantageous properties of the hardened molded part produced according to the present invention. In particular, the one or more aliphatic polymers mentioned above contribute to the good moisture resistance or water resistance, final strength and casting resistance of the hardened molded part produced according to the present invention.

One or more of the aliphatic polymers indicated above, especially one or more of polyvinyl alcohols indicated above, obviously also make an important contribution or even cause the following: produced by the method of the present invention or its preferred variants The favorable low emission characteristics of the hardened molded part, especially low or very low emission of smoke or smoke and/or odorous materials and/or pollutants during or after the metal casting, and the production or Low or very low emissions of odorous materials and/or pollutants in storage. This may be because the aliphatic polymer used according to the present invention contains little or no aromatic components, which is often mentioned as a cause of harmful emissions.

Therefore, the one or more aliphatic polymers to be used in accordance with the present invention preferably do not contain aromatic-containing components and components that cause a considerable degree of emission of smoke, smoke, odor and/or pollutants under the conditions of the method of the present invention. / Or other ingredients.

For the reasons indicated above, it is preferable that the method of the present invention is not carried out in the presence of aromatics-containing organic compounds, or the mold material mixture produced in the method of the present invention does not contain aromatics (that is, in the present invention The mold material mixture produced in the method preferably does not contain, and the ingredients used to produce the mold material mixture are also preferably not contained, any organic compound containing aromatics).

The mold material mixture produced in step V1) preferably does not contain any compound selected from the group consisting of organotin compounds, organoaluminum compounds, dimethylcyclohexylamine, N-substituted pyrrolidone, N- Substituted imidazoles, triazine derivatives, diazabicyclooctane or quaternary ammonium salts (as indicated in WO 2017/071695 A1), which have functions for using one or more polyisocyanates as one or more aliphatic The crosslinking agent of the hydroxyl group of the polymer is used to crosslink the activity of the catalyst of one or more aliphatic polymers (component b)) containing the structural unit of formula I containing the hydroxyl group.

In addition, the method of the present invention as indicated above is also preferred, and the method (ii) according to the present invention is preferred (preferably the above or below indicates the preferred method according to the present invention), where-biopolymer or One or more (or all) of a plurality of biopolymers selected from the group consisting of poly-D-glucosamine comprise polyglucosamine, of which polyglucosamine is preferred-by means of ¹ H NMR spectroscopy Measured, the degree of deacetylation>70 mol%, preferably>75 mol% and particularly preferably>80 mol%, and/or-in each case polymerized at 20°C according to DIN 53015:2001-02 Measured in a 1% strength (w/w) solution of glucosamine in 1% strength (w/w) acetic acid, dynamic viscosity> 500 mPažs, preferably> 600 mPažs, especially preferably ≥ 700 mPažs; and/or- The total mass of the aliphatic polymer containing the structural unit of formula I containing the hydroxyl group used and the total mass of the biopolymer used selected from the group consisting of poly-D-glucosamine, and the total mass of the used The ratio of the total mass of the base mold material is in the range of 0.2:100 to 13:100, preferably in the range of 0.3:100 to 10:100, and particularly preferably in the range of 0.5:100 to 9:100.

In the embodiment of the method of the present invention indicated above, the degree of deacetylation of the polyglucosamine to be used is preferably in the range of 65 mol% to 95 mol%, particularly preferably 70 mol%. It is in the range of ear% to 95 mol%, extremely preferably in the range of 75 mol% to 95 mol%, and particularly preferably in the range of 80 mol% to 95 mol%.

In the embodiment of the method of the present invention indicated above, the dynamic viscosity of the polyglucosamine to be used is preferably in the range of 500 mPažs to 1100 mPažs, particularly preferably in the range of 600 mPažs to In the range of 800 mPažs, very preferably in the range of 700 mPažs to 800 mPažs and particularly preferably in the range of 720 mPažs to 770 mPažs, which in each case is in accordance with DIN 53015:2001-02 Measured by a 1% strength (w/w) solution of polyglucosamine in 1% strength (w/w) acetic acid at 20°C (measured with a Höppler falling ball viscometer).

It has been found that the above-mentioned preferred biopolymers selected from the group consisting of poly-D-glucosamine, especially the above-mentioned preferred polyglucosamine, are particularly suitable for combining with other ingredients to be used according to the present invention to produce mold materials The mixture can first be converted into a molded part with good green strength in step V31), and then further processed in step V32) and preferably additionally converted into a hardened molded part (or in step V33) The cross-linked hardening molding part), which has the above-mentioned advantageous characteristics of the method of the present invention. The use of biopolymers selected from the group consisting of poly-D-glucosamine additionally opens up the possibility of relying at least in part on renewable raw materials for the production of hardened molding parts in the foundry industry.

According to the present invention, it is also preferably at least partly and preferably all, in the form of an aqueous formulation containing one or more biopolymers selected from the group consisting of poly-D-glucosamine, using one or more selected from poly-D -A biopolymer of the group consisting of glucosamine (component c1)) (if present or used) for use in the production of the mold material mixture in step V1). The aqueous preparation to be used in the method of the present invention preferably contains, based on the total mass of the aqueous preparation containing one or more biopolymers, the total amount (concentration) is in the range of 0.5% to 10% by weight, particularly preferably 1 One or more biopolymers selected from the group consisting of poly-D-glucosamine in the range of weight% to 7.5% by weight, and extremely preferably in the range of 1.5 weight% to 5% by weight. The aqueous formulation may additionally contain a suitable amount of one or more suitable acids for partial or complete dissolution of one or more biopolymers. The aqueous formulation preferably contains, based on the total mass of the aqueous formulation, at most 5% by weight, particularly preferably at most 2.5% by weight, one or more selected from the group having a pKa in the range of 3 to 7, preferably in the range of 3.5 to 6.5 The acid in the acid, and preferably does not contain any aromatic organic compound or group. The one or more acids are particularly preferably one or more organic acids, preferably one or more monoprotic organic acids. It is extremely preferred that one acid or at least one of the acids is acetic acid.

Preferably, based on the total mass of the used biopolymer selected from the group consisting of poly-D-glucosamine, ≥90% by weight, preferably ≥95% by weight of one or more selected from the group -A biopolymer of the group consisting of D-glucosamine, preferably polyglucosamine, is present in the aqueous formulation in dissolved form.

Also further preferred is the method of the invention as indicated above, preferably the method (ii) according to the invention (preferably the above or below indicated as the preferred method according to the invention), wherein the component c2 of the mold material mixture) If used or present, it contains one or more aliphatic polyisocyanates, preferably one or more water-dispersible aliphatic polyisocyanates.

Equally preferred is the method of the present invention as indicated above, preferably the method (ii) according to the present invention (preferably the above or below indicated as the preferred method according to the present invention), wherein it is used as the method in step V1) Sub c2) one or more polyisocyanates (if used or present) comprise (one or more) aliphatic polyisocyanates (preferably those which are preferably to be used in the method of the invention and are indicated above and below) In the sense of aliphatic polyisocyanate), preferably (one or more) water-dispersible aliphatic polyisocyanate, Among them, preferably, -One or more or all of an aliphatic polyisocyanate or a plurality of aliphatic polyisocyanates are non-ionic or ionic hydrophilized, And/or -One or more or all of an aliphatic polyisocyanate or a plurality of aliphatic polyisocyanates contain polyether groups or sulfonate groups, And/or -One or more or all of an aliphatic polyisocyanate or a plurality of aliphatic polyisocyanates contain polyether groups, and additional urethane and/or allophanate groups, And/or -One or more or all of an aliphatic polyisocyanate or a plurality of aliphatic polyisocyanates contain one or more 2,4,6-trilateral oxytriazine groups, and preferably polyether groups or sulfonic acids Ester group, preferably polyether group, And/or -One or more or all of an aliphatic polyisocyanate or a plurality of aliphatic polyisocyanates contain one or more 2,4,6-trilateral oxytriazinyl groups and polyether groups, and an additional aminomethyl group Acid ester and/or allophanate groups, preferably urethane groups, And/or -One or more or all of an aliphatic polyisocyanate or a plurality of aliphatic polyisocyanates include self-emulsifying and/or self-water-emulsifiable aliphatic polyisocyanate, And/or -The one or more aliphatic polyisocyanates used constitute ≥50% by weight of all the one or more polyisocyanates used in the molding material mixture, preferably ≥75% by weight, particularly preferably ≥90% by weight and very preferably ≥ 98% by weight.

The aliphatic polyisocyanates preferably to be used in the process of the invention and described or defined in more detail above are also water-dispersible aliphatic polyisocyanates in the context of the invention.

In a preferred embodiment of the above-mentioned preferred variant of the method of the present invention, one or more aliphatic polyisocyanates are used (preferably indicated above or below as the preferred aliphatic polyisocyanates to be used in the method of the present invention ) Constitute 100% by weight of the total mass of all one or more polyisocyanates used in the mold material mixture.

The above-mentioned one or more polyisocyanates to be used according to the present invention, preferably one or more aliphatic polyisocyanates to be used according to the present invention, preferably an aliphatic polyisocyanate having at least two free isocyanate groups, so that it is suitable To cross-link with free hydroxyl groups of aliphatic polymers containing hydroxyl-containing structural units of formula I.

The aforementioned one or more aliphatic polyisocyanates to be used according to the invention or preferably to be used according to the invention preferably comprise aliphatic and/or cycloaliphatic polyisocyanates. For the reasons indicated above (to avoid the emission of smoke, smoke, odorous materials and/or pollutants from the molded part produced by the method of the present invention, better water compatibility or water dispersibility), The aliphatic polyisocyanate to be used according to the invention or preferably according to the invention preferably does not contain any aromatic groups (that is, does not contain aromatics).

The one or more aliphatic polyisocyanates that have been described or defined in more detail above and are preferably to be used in accordance with the present invention are preferably self-emulsifying or self-emulsifying aliphatic polyisocyanates, as described, for example, by Ulrich Meier-Westhues Book: "Polyurethane-Lacke, Kleb- und Dichtstoffe", Hanover: Vincentz Network 2007 (ISBN: 3-86630-896-5 or 978-3-86630-896-1), pages 43-46.

The one or more aliphatic polyisocyanates that have been described or defined in more detail above and are preferably to be used in accordance with the present invention preferably comprise aliphatic polyisocyanates selected from the group consisting of: -Polyether urethane type non-ionic hydrophilized aliphatic polyisocyanate, such as Bayhydur® 3100, Bayhydur® VP LS 2306, Desmodur® DA-L and Desmodur® DN -Polyether allophanate type non-ionic hydrophilized aliphatic polyisocyanate, such as Bayhydur® 304 and Bayhydur® 305 and -Nonionic hydrophilized aliphatic polyisocyanates of sulfonate type, such as Bayhydur® XP 2487/1, Bayhydur® XP 2547, Bayhydur® XP 2570 and Bayhydur® XP 2655.

Particularly preferably, one or more aliphatic polyisocyanates to be used in the method of the present invention are selected from the group consisting of: non-ionic hydrophilic aliphatic polyisocyanates of the polyether urethane type, such as Bayhydur® 3100, Bayhydur® VP LS 2306, Desmodur® DA-L and Desmodur® DN. The aliphatic polyisocyanate that is very best to be used in the method of the present invention is Desmodur® DA-L (CAS RN 125252-47-3).

It has been found that, under the conditions of the method of the present invention, that is, in an aqueous mixture or an aqueous binder system, the above-mentioned preferred self-emulsifying or self-emulsifying aliphatic polyisocyanates are extremely suitable for containing hydroxyl-containing structural units of formula I One or more crosslinking agents for aliphatic polymers.

In a variant of the method of the invention, wherein the mold material mixture produced in step V1) contains (at least) component c2) as curing agent component c), one or more polyisocyanates, as one or more aliphatic polymers The hydroxy crosslinking agent (only or, preferably, except for component c1), is preferably the method according to the invention described above, preferably the method (ii) of the invention (preferably indicated above or below) Is a preferred method according to the present invention), which comprises one or more aliphatic polymers (component b)) containing hydroxyl-containing structural units of formula I and one of the crosslinking agents as the hydroxyl groups of one or more aliphatic polymers or A variety of polyisocyanates (component c2)) are provided as or used as the first binder system in the form of an aqueous mixture, which comprises: b) One or more aliphatic polymers comprising a hydroxyl-containing structural unit of formula I -CH ₂ -CH (OH)-(I), and c2) One or more polyisocyanates (as defined above or below or preferably defined as crosslinking agents for the hydroxyl groups of one or more aliphatic polymers).

The above-mentioned aqueous mixture to be used as the first binder system (hereinafter also referred to as the "first binder system") used to produce the mold material mixture in step V31) of the method of the present invention preferably includes, The total mass of a binder system is included in the range of 5% to 40% by weight, particularly preferably in the range of 7.5% to 35% by weight and very preferably in the range of 10% to 30% by weight One or more aliphatic polymers of formula I structural units containing hydroxyl groups.

The above-mentioned first adhesive system to be used in the method of the present invention preferably comprises, based on the total mass of the first adhesive system, the total amount is in the range of 1% to 20% by weight, particularly preferably 2.5% to One or more polyisocyanates in the range of 15% by weight and very preferably in the range of 3% to 10% by weight (defined or defined above or below as preferred), preferably one or more aliphatic polyisocyanates.

In a preferred variant of the above-mentioned method according to the invention, the components b), c2) (in each case as defined above) and d) water in the aqueous mixture as the first binder system are by weight The total proportion is 100% by weight, which is the total mass of the aqueous mixture as the first binder system.

Preferably, based on the total mass of the aliphatic polymer used, ≥90% by weight, particularly preferably ≥95% by weight, of the aliphatic polymer containing the hydroxyl-containing structural unit of formula I is present in the dissolved form as the first In an aqueous mixture of a binder system.

In the variant of the method of the invention indicated above or below, wherein the mold material mixture produced in step V1) contains (at least) component c2) as the curing agent component c), one or more polyisocyanates (as above As defined or defined in the text or below is preferred), as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers (only or, preferably, except for component c1)), preferably only in the upcoming production The components b) and c2) of the molding material mixture are brought into contact with each other before the molding material mixture, preferably no earlier than one hour before the molding material mixture is produced. In this way, the undesired premature start of the crosslinking reaction of one or more polyisocyanates and one or more aliphatic polymer hydroxyl groups is prevented (for example, in the absence of a base mold material).

My own experiments have also shown that if the amount or substance ratio indicated above is used in step V1), the component b) of the mold material mixture, one or more aliphatic polymers, and C2), one or more polyisocyanates (as above As defined or defined in the text or below), a molding material mixture that is particularly suitable for processing and molding in, for example, a blow molding machine or a molded part cassette (such as a core cassette) is obtained.

In addition, my own experiments have shown that a better variant of the method of the present invention, in which one or more aliphatic polymers (component b)) and one or more polyisocyanates (component c2)) are used as the first adhesive in the form of an aqueous mixture Agent system, so that the components b) and c2) are particularly uniformly mixed with each other, so that, for example, the crosslinking of the hydroxyl group of one or more aliphatic polymers and the isocyanate group of the polyisocyanate crosslinking agent (step V33)) is especially It proceeds completely, and therefore the molding material mixture (or the unhardened downstream product formed therefrom) is particularly completely and uniformly transformed into a hardened molding part, or a crosslinked hardened molding part.

In a preferred variant of the method of the present invention, wherein the mold material mixture produced in step V1) contains component c1) as the curing agent component c), one or more selected from the group consisting of poly-D-glucosamine Biopolymers, and component c2), one or more polyisocyanates, as crosslinking agents for the hydroxyl groups of one or more aliphatic polymers, preferably the method of the invention as indicated above, preferably the method of the invention (ii) (preferably indicated above or below is the preferred method according to the present invention), wherein components b), c1) and c2) are provided as or used as a second binder system in the form of an aqueous mixture, which comprises: b ) One or more aliphatic polymers comprising a structural unit of formula I containing hydroxyl groups -CH ₂ -CH(OH)- (I), c1) One or more organisms selected from the group consisting of poly-D-glucosamine Polymer and c2) One or more polyisocyanates (as defined above or below or as preferred) as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers, preferably one or more aliphatic polyisocyanates.

In the method of the present invention, the above-mentioned aqueous mixture to be used as the second adhesive system (hereinafter also referred to as the "second adhesive system") preferably contains, based on the total mass of the aqueous second adhesive system, the total amount is 5 wt% to 30 wt%, particularly preferably in the range of 7.5% to 25% by weight, and very preferably in the range of 10% to 20% by weight, one or more polyisocyanates (as defined or defined above or below Is preferred), preferably one or more aliphatic polymers containing a structural unit of formula I containing a hydroxyl group.

In the method of the present invention, the above-mentioned aqueous mixture to be used as the second adhesive system preferably contains, based on the total amount of the aqueous second adhesive system, the total amount is in the range of 0.25% to 5% by weight, particularly preferably One or more biopolymers selected from the group consisting of poly-D-glucosamine in the range of 0.4% to 3.5% by weight, and very preferably in the range of 0.5% to 2.5% by weight.

The above-mentioned second adhesive system to be used in the method of the present invention preferably includes, based on the total mass of the aqueous second adhesive system, the total amount is in the range of 1% to 15% by weight, particularly preferably 2% by weight One or more polyisocyanates in the range of to 10% by weight and very preferably in the range of 2.5% to 7.5% by weight (as defined above or below or as preferred), preferably one or more aliphatic polyisocyanates.

In a preferred variant of the above method of the present invention, the components b), c1), c2) (in each case as defined above) and d) water in the aqueous mixture as the second binder system are by weight The total ratio is 100% by weight, which is the total mass of the aqueous mixture used as the second binder system.

Preferably, based on the total mass of the aliphatic polymer used, ≥90% by weight, particularly preferably ≥95% by weight, used as the second binder system in the form of an aqueous mixture contains a structural unit of formula I containing a hydroxyl group The aliphatic polymer exists in dissolved form.

It has been found that a preferred variant of the method of the invention includes one or more aliphatic polymers (component b)) and one or more biopolymers selected from the group consisting of poly-D-glucosamine (component c1)) And one or more polyisocyanates (component c2)) are used in the form of a second binder system, so that their components are particularly homogeneously mixed with each other, so that, in particular, the hydroxyl groups of one or more aliphatic polymers and the isocyanate groups of the crosslinking agent are in the base mold The cross-linking in the presence of the material proceeds particularly completely, and therefore the molding die material mixture is particularly completely and uniformly transformed into a hardened molded part, or converted into a cross-linked hardened molded part.

Also preferred is the method of the present invention as indicated above, preferably the method (ii) according to the present invention (preferably the above or below indicates the preferred method according to the present invention), wherein -Used (in step V1) to produce the total mass of one or more aqueous mixtures of mold material mixtures The one or more aqueous mixtures are preferably selected from the group consisting of: an aqueous mixture containing one or more aliphatic polymers containing hydroxyl-containing structural units of formula I, and containing one or more selected from poly-D-glucosamine Aqueous formulations of biopolymers of the group consisting of the aqueous mixture of the first binder system and the aqueous mixture of the second binder system; versus -(In step V1)) the total mass of the base mold material used - The ratio It is in the range of 1:100 to 50:100, preferably in the range of 1.5:100 to 40:100, and particularly preferably in the range of 2:100 to 35:100.

It is better to set the above-mentioned (numerical value) ratio of the total mass of one or more aqueous mixtures to the total mass of the base mold material used, so as to produce a mold that can be shot or punched to obtain a mold or core And the mold material mixture of the molding part of the group consisting of the supply port. In this case, it has been found that the ratio suitable for a particular situation (in each case, the concentration of the aqueous mixture used does not change) depends in particular on the type of base mold material used: therefore, in which a relatively low bulk density is used In the case of the base mold material (preferably silica sand), the above-mentioned suitable numerical ratio is usually in a higher range (that is, closer to the upper limit of 50:100 or 40:100), and the use thereof has a relatively high bulk density In the case of the basic mold material (preferably silica sand), the above suitable numerical ratio tends to be in a lower range (that is, closer to the lower limit of 1:100 or 1.5:100).

Also preferred is the method according to the invention as indicated above, preferably the method according to the invention (ii) (preferably the above or below indicated as the preferred method according to the invention) (preferably the method according to the invention, Wherein the mold material mixture contains component c1) as the curing agent component c), one or more biopolymers selected from the group consisting of poly-D-glucosamine, and additionally component c2), one or more polyisocyanates) , among them -The total mass of the aliphatic polymer containing the hydroxyl-containing structural unit of formula I used and -The total mass of the biopolymer used (if present or used) selected from the group consisting of poly-D-glucosamine Sum of versus -The total mass of the preferred aliphatic polyisocyanate (if present or used) used as a crosslinking agent - The ratio It is in the range of 1:1 to 10:1, preferably in the range of 1.5:1 to 7.5:1, and particularly preferably in the range of 2:1 to 5:1.

It has been found that when the above-mentioned biopolymer selected from the group consisting of poly-D-glucosamine (component c1)) is used in the above-mentioned amount and ratio, an aliphatic polymer comprising a structural unit of formula I containing a hydroxyl group (component b) ) And the preferred aliphatic polyisocyanate used as a crosslinking agent (component c2) when the method of the present invention is carried out, produces a good green strength, and the hydroxyl group of one or more aliphatic polymers and the isocyanate group of the crosslinking agent The cross-linking step (step V33)) is significantly suitable for the further processed molded part according to the method of the present invention, so that the molded part with good green strength can be converted into The hardened shaped part or (by means of step V32) and additionally step V33)) is transformed into a crosslinked hardened shaped part.

Also preferred is the method of the present invention as indicated above, preferably the method according to the present invention (ii) (preferably the above or below indicates the preferred method according to the present invention), The (at least one) basic mold material includes: -One or more refractory solid particles preferably selected from the group consisting of: -Oxides, silicates and carbides, in each case contain one or more elements from the group consisting of Si, Al, Zr, Ti, Mg, Fe and Ca, -Mixed oxides, mixed carbides and mixed nitrides, in each case containing one or more elements from the group consisting of Si, Al, Zr, Ti, Mg, Fe and Ca, and -Graphite And/or -One or more particulate lightweight fillers, which are preferably selected from the group consisting of: -Core-shell particles, which preferably include a glass core and a refractory shell, and particularly preferably have a bulk density in the range of 470-500 g/l, preferably as described in document WO 2008/113765 A1; -Fire-resistant composite particles, preferably as described in document WO 2017/093371 A1 or produced according to document WO 2017/093371 A1; -A sphere, preferably a sphere made of fly ash, such as the sphere "Fillite 106" from Omya GmbH; -Perlite, preferably expanded perlite, such as the expanded perlite named "Eurocell 140", "Eurocell 145", "Eurocell 150" or "Eurocell 300" especially from RS Rohstoff-Sourcing GmbH; -Closed-cell microspheres composed of expanded perlite, preferably as described in document WO 2017/174826 A1; -Rice husk ash, preferably as described in document WO 2013/014118 A2; -Expanded glass, -Hollow glass ball and -Hollow ceramic balls, preferably hollow α-alumina balls.

The one or more particulate refractory solids described above can be used alone or in combination with each other and thus form the base mold material to be used in the method of the present invention. Likewise, one or more of the aforementioned particulate lightweight fillers can be used alone or in combination with each other and thus form the base mold material to be used. Naturally, it is also possible to combine one or more particulate refractory solids and one or more particulate lightweight fillers as the base mold material and thus form the base mold material to be used. Depending on the purpose of the method of the present invention to be used, that is, depending on the hardened molded part to be produced, those familiar with the art will choose the basic mold material suitable for each situation. For example, only silica sand can be selected as the base mold material for producing simple molds. In addition, for example, a mixture of silica sand and one or more particulate lightweight fillers can be selected to create a replenishment port, or one or more particulate lightweight fillers can be exclusively selected, which are preferably selected from the above The preferred group of lightweight fillers is defined for this purpose.

In addition to the above-mentioned preferred components, the base mold material to be used in the method of the present invention may further include components of preferred particles, which are preferably selected from the group consisting of elemental metals (such as aluminum), oxidizers, and ignition agents. Therefore, for example, in order to generate heat-generating replenishment ports, in addition to the above-mentioned components (selected from refractory solids and lightweight fillers), the base mold material to be used may also contain aluminum, iron oxide, which are known per se for this purpose. The oxidizing agent and the ignition agent known per se for this purpose.

Also preferred is the method of the present invention for producing metal castings as indicated above, preferably method (i) according to the present invention (preferably the above or below indicated as the preferred method according to the present invention), the method There are the following additional steps (preferably after step V32) and/or step V33) have been performed, especially preferably after both steps V32) and V33) have been performed): V4) The hardened forming part, preferably obtained after step V32) and preferably additionally step V33), is brought into contact with the cast metal for the production of metal castings, wherein the cast metal is preferably in contact with the hardened forming part solidification, Among them, preferably, -The cast metal is selected from the group consisting of aluminum, magnesium, tin, zinc and their alloys And/or -The temperature of the cast metal during casting does not exceed 900°C; This produces metal castings.

In the preferred method according to the present invention for producing metal castings described above, the cast metal is at least partially and preferably completely liquid when contacting the hardened shaped part or the cross-linked hardened shaped part. Any castable metal or any castable metal alloy, especially light metals and their alloys, such as aluminum, magnesium, tin, and zinc; and iron and steel, are suitable as cast metals.

It has been found that in our experiments, the amount of soot or smoke or smoke is formed and hardly or ideally does not produce gaseous emissions that are potentially harmful to human health, for example, in accordance with the present invention The resulting hardened molded part, especially when the cross-linked hardened molded part produced according to the present invention is in contact with the cast metal, will decompose the cross-linked adhesive in the cross-linked hardened molded part under the action of the heat of the liquid casting metal. What is the nature of the cast metal? This applies even at relatively low temperatures in the range of 600°C to 900°C, making the above-mentioned preferred method variant (i) extremely suitable for producing metal castings when the cast metal is light metal or light metal alloy: Under the relatively low temperature (compared to the temperature in the casting of iron or steel) commonly used in the casting, the conventional cold box adhesives frequently used at present often only incompletely thermally decompose, so that in these cases, the metal casting And in the unwrapping mold, there are particularly strong formation of smoke, smoke and soot, and the substantial release of gaseous aromatic-containing emissions, which are usually accompanied by unpleasant odors and potentially harmful to human health.

On the other hand, when using the hardened molded part produced by the method of the present invention, or when performing the above-mentioned preferred method variant (i) according to the present invention, especially the preferred method variant (i) described herein , Such shortcomings appear to a significantly lower degree, or not appear at all under ideal circumstances. Since a particularly serious emission hazard occurs during the metal casting process, with the help of the replenishment port or replenishment port cover at the contact surface of the mold and the ambient air, it appears from the replenishment port or replenishment port cover, so the replenishment port or replenishment port cover is the present invention When the hardened molded part in the method is produced (method variant (ii)) or used (method variant (i)), especially when it has been crosslinked in the method of the present invention (in step V33)), The above-mentioned preferred method variant (i) according to the invention is particularly effective.

The present invention further provides a hardened molding part selected from the group consisting of a mold, a core, and a replenishment port for casting metal castings, which can preferably be obtained by the above-mentioned method (ii) according to the present invention (preferably by the above Or the following instructions are preferably produced according to the method of the present invention. The hardened molded part contains the following ingredients: a) at least one base mold material, b) one or more aliphatic polymers, which contain hydroxyl-containing structural units of formula I -CH ₂ -CH(OH)- (I), and c) as the curing agent component, one or more ingredients selected from the group consisting of: c1) one or more preferably precipitated from poly-D-glucosamine The group consisting of sugar amines, preferably biopolymers containing polyglucosamine, and c2) one or more preferably aliphatic, especially water-dispersible aliphatic polyisocyanates, wherein the polyisocyanates used include hydroxyl-containing The hydroxyl group of the aliphatic polymer (component b)) of the structural unit of formula I is preferably at least partially hardened, preferably by crosslinking and hardening by crosslinking with the isocyanate groups of one or more polyisocyanates used Exist in dosage form.

Regarding the preferred embodiments of the hardened molding part according to the present invention and the possible combinations of one or more associated aspects and each other, the explanations given above for the method of the present invention apply similarly, and vice versa.

Preferably, it has good green strength and contains component c1) as the curing agent component c). One or more precipitates selected from the group consisting of poly-D-glucosamine, preferably containing polyglucosamine The molded part of the polymer serves as the above-mentioned hardened molded part according to the present invention.

If the molded part with good green strength according to the present invention additionally contains component c2), one or more preferably aliphatic, especially water-dispersible aliphatic polyisocyanates, then these one or more polyisocyanates And one or more aliphatic polymers containing hydroxyl-containing structural units of formula I are preferably not cross-linked (with each other) in the molded part with good green strength.

As the above-mentioned hardening molding part according to the present invention, it is also preferable to include component c2) as the curing agent component c), one or more preferably aliphatic, especially water-dispersible aliphatic polyisocyanate (Cross-linking) hardening molding part, wherein the aliphatic polymer (component b)) containing hydroxyl-containing aliphatic polymer (component b)) is used at least partially by combining with one or more polyisocyanates (component c2 )) The isocyanate group is cross-linked and cross-linked and cured in the form of an adhesive.

If the hardening (or cross-linking hardening) molding part according to the present invention contains the hydroxyl group of the aliphatic polymer (component b)) containing the hydroxyl-containing structural unit of formula I and one or more polyisocyanates used (Component c2)) The isocyanate group crosslinked and crosslinked adhesive, for the purpose of the present invention, it is assumed that after the isocyanate group crosslinked by one or more polyisocyanates used, the molding part according to the present invention The hydroxyl groups of the crosslinked or crosslinked aliphatic polymer (at least predominantly) no longer exist in free form, but (at least predominantly) participate in the formation of urethane groups via isocyanate groups.

The present invention also provides a hardened molding part selected from the group consisting of molds, cores and replenishment ports by the method according to the invention as indicated above, preferably by the method (ii) according to the invention (or According to the preferred method of the present invention described herein) produced or can be produced.

Regarding the preferred embodiments of the hardened forming part produced or produced according to the present invention and the possible combinations of one or more related aspects and each other, the above explanations are given for the method of the present invention and the hardened forming part of the present invention The same applies, and vice versa.

The (cross-linked) hardened molded part according to the present invention as indicated above (or the correspondingly preferred cross-linked hardened molded part according to the present invention described herein, or the cross-linked molded part that can be produced by the above-mentioned method according to the present invention Joint hardening forming part), where -The total mass of the hardened adhesive present in the molded part versus -The ratio of the total mass of the base mold material existing in the molding part It is in the range of 0.1:100 to 10:100, preferably in the range of 0.5:100 to 7:100 and particularly preferably in the range of 0.6:100 to 6:100.

The present invention also provides a mold material mixture, which is preferably used to produce hardened molded parts (including molded parts with good green strength) selected from the group consisting of molds, cores and replenishment ports for casting metal castings. Component c1) exists as a curing agent component, and/or a cross-linked hardening molding part, if component c2) exists as a curing agent component), the mold material mixture contains the following components: a) at least one base mold material, b) One or more aliphatic polymers containing hydroxyl-containing structural unit of formula I -CH ₂ -CH(OH)- (I), c) as a curing agent component, one or two components selected from the group consisting of : C1) one or more biopolymers selected from the group consisting of poly-D-glucosamine, preferably polyglucosamine, and c2) as one of the crosslinking agents of the hydroxyl group of one or more aliphatic polymers or A variety of polyisocyanates with better water dispersibility and/or aliphatic; and d) water.

In a particularly preferred variant of the above-mentioned mold material mixture of the present invention, this comprises component c1) as the curing agent component c), one or more selected from poly-D-glucosamine, preferably polyglucosamine The group of biopolymers, and additionally component c2), one or more preferably aliphatic polyisocyanates, as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers.

In a preferred variant of the above-mentioned mold material mixture of the present invention, this only contains component c1) as the curing agent component c), one or more selected from poly-D-glucosamine, preferably polyglucosamine The group of biopolymers, but does not contain component c2), one or more preferably water-dispersible and/or aliphatic polyisocyanates, as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers.

In another preferred variant of the above-mentioned mold material mixture of the present invention, this comprises only component c2) as the curing agent component c), one or more aliphatic polyisocyanates (preferably in this context as in accordance with the present invention It is preferable to use one or more aliphatic polyisocyanates) as a crosslinking agent for the hydroxyl groups of one or more aliphatic polymers, but does not contain component c1), one or more selected from poly-D-glucosamine, preferably A group of biopolymers composed of polyglucosamine.

Regarding the preferred embodiment of the mold material mixture of the present invention and the possible combination of one or more associated aspects and each other, the above is directed to the method of the present invention, the hardening molding part of the present invention, and the hardening produced or can be produced according to the present invention. The explanations given in the forming part apply similarly, and vice versa.

The above-mentioned mold material mixture according to the present invention (or the above-mentioned mold material mixture according to the present invention indicated as preferred herein) is suitable for the above method of the present invention and is provided for this purpose.

The present invention also provides the use of an aliphatic polymer, which comprises a structural unit of formula I containing hydroxyl groups -CH ₂ -CH(OH)- (I). These hydroxyl groups have been cross-linked by one or more aliphatic polyisocyanates. Preferably, the polyvinyl alcohol crosslinked in this way is used as a binder for the hardened molding part selected from the group consisting of a mold, a core, and a replenishment port for casting metal castings.

Regarding the preferred embodiments of the use according to the present invention and the possible combinations of one or more associated aspects with each other, the above is directed to the method of the present invention, the hardening molded part according to the present invention, the hardening produced or can be produced according to the present invention The explanations given for the molding part and the mold material mixture according to the invention apply similarly, and vice versa.

The present invention further provides a use of biopolymers selected from the group consisting of poly-D-glucosamine, preferably polyglucosamine, which are used as binders or binder components for the production of molds selected from The hardened molding part in the foundry industry consisting of the core and the replenishment port is preferably the molding part with good green strength.

With regard to the preferred embodiments of the use of biopolymers in accordance with the present invention and the possible combinations of one or more related aspects and each other, the above is directed to the method of the present invention, the hardened molded part of the present invention, produced according to the present invention or can be produced The explanations given for the use of the invention according to the explanation given for the use of the invention, and vice versa, apply similarly to the hardened molding part of the invention, the mold material mixture of the invention and the aliphatic polymer crosslinked by one or more aliphatic polyisocyanates.

Examples : The examples given below are intended to illustrate and explain the present invention in more detail without limiting the scope of the present invention.

Unless otherwise specified, the experiment was carried out under laboratory conditions (normal pressure, temperature 20°C, atmospheric humidity 50%) in each case.

Instance 1 : Production of mold material mixture The ingredients indicated in Table 1 below and described in more detail below Table 1 were used to create the mold material mixture.

The mold material mixtures "F-cold box" and "F-water glass" are comparative mold material mixtures to be used not according to the present invention or according to the present invention. The mold material mixtures "F-V6" and "F-E6+" are the mold material mixtures to be used according to the present invention or according to the present invention. Table 1 : Composition of mold material mixture ingredient Mold material mixture F- cold box F- water glass F-V6 F-E6+ Silica sand BO42 [parts by weight] 100 100 100 100 Water-based PVAL mixture [parts by weight] 0 0 3.6 3.428 Aliphatic polyisocyanate [parts by weight] 0 0 0 0.286 Aqueous preparation of polyglucosamine [parts by weight] 0 0 2.4 2.286 Cold box activator 6324 [parts by weight] 1.2 0 0 0 Cold box gas resin 7241 [parts by weight] 1.2 0 0 0 Sodium water glass adhesive 48/50 [parts by weight] 0 1.5 0 0

Silica sand BO 42 (CAS No. 014808-60-7) from Bodensteiner Sandwerk GmbH & Co. KG was used as the base mold material.

As an aqueous PVAL mixture, 25% by weight strength polyvinyl alcohol (>93% polyvinyl alcohol) solution is used, with a degree of hydrolysis of about 88 mol% and a dynamic viscosity in the range of 3.5 to 4.5 mPa·s (according to DIN 53015 , Measured as a 4 wt% strength aqueous solution at 20°C), methanol content: 3 wt%; CAS RN 25213-24-5 (Kuraray Europe GmbH).

As the aliphatic polyisocyanate, a polyether urethane type non-ionic hydrophilic polyisocyanate "Desmodur® DA-L" (Covestro AG) (CAS RN 125252-47-3) is used.

As an aqueous preparation of polyglucosamine, use 2.5% by weight strength (based on the total mass of the solution) polyglucosamine 85/1000 (deacylation degree of 85 mol% and dynamic viscosity of 1000 mPažs, according to Manufacturer Information: Heppe Medical Chitosan GmbH) in 1% by weight strength acetic acid aqueous solution (based on the total mass of the solution).

As the cold box activator 6324, polyisocyanate (activator 6324 from Hüttenes-Albertus Chemische Werke GmbH) conventionally used for producing cold box adhesives (polyurethane resin based on benzyl ether) was used.

As the cold box gas resin 7241, a phenol resin (gas resin 7241 from Hüttenes-Albertus Chemische Werke GmbH) conventionally used for producing cold box adhesives (polyurethane resin based on benzyl ether) is used.

As sodium water glass adhesive 48/50, use the aqueous solution of standard water glass adhesive, the water glass content (sodium silicate content) is in the range of 35% to 50% by weight and the pH value is between 11 and 11 at 20°C Within 12 (CAS RN 1344-09-8).

Create the mold material mixture as indicated below: Molding material mixture F-cold box: The ingredients indicated in Table 1 were mixed with each other by stirring in an electric mixer (Bosch Profi 67) until a homogeneous mold material mixture was formed. For comparison purposes, a mold material mixture cold box is a mold material mixture that has not been produced by the method of the present invention or is not used in such methods.

Mold material mixture F-water glass: The ingredients indicated in Table 1 were mixed with each other by stirring in an electric mixer (Bosch Profi 67) until a homogeneous mold material mixture was formed. For comparison purposes, the mold material mixture F-water glass is a mold material mixture that has not been produced by the method of the present invention or is not used in such methods.

Mold material mixture F-V6: Mix the ingredients indicated in Table 1 "aqueous PVAL mixture" and "aqueous preparation of polyglucosamine" in a glass beaker in the amount indicated in Table 1 to obtain a premixed adhesive Things. The silica sand was then placed in an electric mixer (Bosch Profi 67), and then the binder premix was added while stirring and mixing with the silica sand. Continue stirring until a homogeneous mold material mixture is formed. The mold material mixture F-V6 is a mold material mixture produced by the method of the present invention or to be used in such methods.

Molding material mixture F-E6+: Mix the ingredients indicated in Table 1 "aqueous PVAL mixture" and "aqueous preparation of polyglucosamine" in a glass beaker in the amount indicated in Table 1 to obtain a premixed adhesive Things. Shortly before the production of the mold material mixture F-E6+, the amount of aliphatic polyisocyanate indicated in Table 1 was added to the formed adhesive premix and mixed with each other (agitating movement using a wing mixer) And combined with the adhesive premix to obtain a "second adhesive system" (in the sense of the present invention). The silica sand was then placed in an electric mixer (Bosch Profi 67), and then the formed second binder system was added while stirring and combined with the silica sand by mixing. Continue stirring until a homogeneous mold material mixture is formed. The mold material mixture F-E6+ is a mold material mixture produced by the method of the present invention or to be used in such methods.

Instance 2 : Production of standard bending test strips as an illustrative forming part For testing purposes, standard bending test strips (representing the hardened and formed parts used for casting metal castings) were generated from the mold material mixtures F-cold box, F-water glass, F-V6 and F-E6+ indicated in Example 1, It is produced by a method known to those familiar with the technology (size: 172×23×23 mm), which corresponds to or is similar to Verein Deutscher Gießereifachleute's manual P73 (version in February 1996) (hereinafter referred to as It is the method in Article 4.1 of "VDG Manual P73").

The bending test strip described above is hardened as indicated below (the method used to harden the mold material mixture "F-cold box" and "F-water glass", which corresponds to the method known from the prior art as indicated below ): Bend test strip B-cold box: The mold material mixture F-cold box (see Example 1) is shaped by tamping in the bend test strip tamping mold as described above. Then by the cold box method, the gaseous N,N-dimethylpropylamine (approximately 1 ml liquid, 15 s) is passed through the molding material mixture (under the method conditions) to harden the molding material mixture, which corresponds to Method A in Article 4.3 of VDG Manual P73.

Bend test strip B-water glass: The mold material mixture F-water glass is formed by tamping in the bending test strip ramming mold as described above. The gaseous CO ₂ then passes through the mold material mixture (in the bending test strip tamping mold). After treatment with CO ₂ gas, the bending test strip with good green strength was taken out from the mold (de-molded) and dried by drying in a drying oven at 210°C for 20 minutes, and by convective degassing in the drying oven Remove water to harden (standard bending test strip here: bending test strip B-water glass).

Bend test strips B-V6 and B-E6+: mold material mixtures F-V6 and F-E6+ (for production, see Example 1) in each case by tamping in the bending test strip tamping mold as described above To shape. The gaseous N,N-dimethylpropylamine (corresponding to about 1 ml of liquid, 15 s) is then passed through the molding material mixture (under the method conditions) (gas treatment in the ramming mold of the bending test strip), in each case Produce standard bending test strips with good green strength ((that is, the illustrative hardened molded part, where it has good green strength). Then these standard bending test strips with good green strength are self-punched. Take it out, and process it in a drying oven at 210°C for 20 minutes in each case, and remove the water by convection deaeration in the drying oven to obtain a hardened molded part (standard bending test strip here: bending test strip B- V6) or hardened molded part with cross-linking step (bend test strip B-E6+).

Instance 3 : Determination of the ultimate strength of standard bending test strips Test the final strength of the standard bending test strip produced in Example 2 above in each case: For this purpose, the final strength of the standard bending test strip B-cold box was tested 24 hours after production. For this purpose, the final strength of the standard bending test strips B-water glass, B-V6 and B-E6+ was tested 30 minutes after they were produced (dried) in each case. All standard bending test strips are stored under laboratory conditions. In each case, the final strength was measured in triplicate, as described in Article 5.2 of the VDG Manual P73, using a Georg Fischer strength test device model PFG with low pressure pressure gauge (with motor drive).

In this way, the bending strength (final strength) of the standard bending test strip as shown in Table 2 below was measured: Table 2 : The final strength of the standard bending test strip Bend test strip: B- cold box B- water glass B-V6 B-E6+ Bending strength [N/cm ² ] 720 750 530 620

From the values reported in Table 2, it can be seen that although the hardened molded parts (standard bending test strips) B-V6 and B-E6+ produced by the method of the present invention are lower than the conventional cold box or water glass bonded parts However, the final strength of the hardened molded part produced by the method of the present invention is completely satisfactory in practice. The standard bending test strip B-E6+ (produced by the cross-linking step) has a higher final strength value (close to the cold box combined bending test strip) than the standard bending test strip B-V6 (produced without the cross-linking step). Corresponding value).

Instance 4 : Determination of the strength of standard bending test strips after aging The standard bending test strips B-water glass and B-E6+ produced in Example 2 above began to undergo the storage test 24 hours after they had been produced (corresponding to the aging time "0"). For this purpose, the corresponding bending test strip was stored in an air-conditioned cabinet at 40°C and 90% relative atmospheric humidity for 60 hours, and tested at the time interval indicated in Table 3 to determine its value as indicated in Example 3 (the remaining )Bending strength. The values of these bending strengths measured in each case are reported in Table 3 below:table 3 : Bending strength after 60 hours of aging in an air-conditioned cabinet Bend test strip: B- water glass B-E6+ Aging time Bending strength [N/cm ² ] 0 750 620 8 h 750 260 12 h 480 290 24 h 120 290 36 h 150 270 48 h 110 260 60 h 50 270

From the values reported in Table 3, it can be seen that the hardened molded part (standard bending test strip) B-E6+ produced by the method of the present invention exhibits a decrease in strength after being stored for 8 hours under storage conditions. However, its strength then remains approximately constant during the remaining storage time and is satisfactory for practical purposes. In contrast, in the case of the water glass combined with the comparative bending test strip B-water glass, a significant decrease in strength was observed after a storage time of 24 hours, and this further progressed to the end of the storage time, until the bending test strip was useful for practical purposes In terms of not available.

Therefore, the hardened molded part produced by the method of the present invention (standard bending test strip, produced by a cross-linking step) B-E6+ is significantly better than the conventional water glass bonded molded part, even under severe weather conditions (high temperature and atmospheric humidity) , More suitable for storage.

Instance 5 : Determination of water resistance of standard bending test strips The standard bending test strip as produced in Example 2 above was placed on the shelf so that only its end was supported (the contact area was about 1/10 of the total area of the lower surface of the standard bending test strip). The shelf on which the standard bending test strip is placed is introduced into a container filled with water in such a way that the lower surface of the standard bending test strip is in full contact with the water surface and water can be absorbed by capillary force. Subsequently, after a period of time indicated in Table 4 below, the water resistance of the standard bending test strip was visually evaluated.

The results of this test are reported in Table 4 below. Table 4 : Water resistance of standard bending test strips Test duration Bend test strip ( observation ) B- cold box B-V6 B-E6+ 0 intact intact intact 3 s intact The upper side shows wet intact 37 s intact Fully moisturized intact 82 s intact Sag in the middle intact 351 s intact Break in the middle intact

From the observation results indicated in Table 4, it can be seen that the standard bending test strips bonded by means of cold box adhesives are completely water resistant even after the longest contact time as indicated in Table 4. The hardened bend test strip B-V6 produced by the method of the present invention (produced in the absence of a cross-linking step) absorbs water after a short time and breaks after some time. The bending test strip B-E6+ produced according to the present invention has higher water resistance than the hardened (uncrosslinked) bending test strip B-V6.

Instance 6 : Behavior of standard bending test strips in iron casting The standard bending test strips B-cold box (comparative group), B-V6 (produced by the method of the present invention) and B-E6+ (produced by the method of the present invention) produced in the above example 2 were used in a manner known per se. Known alcohol-based refractory coating (Koalid 4087 from Hüttenes-Albertus GmbH) coating (conditions: running-out time 17.3 s; immersion time 7 s; drying at 110°C for 40 minutes; in a wet state The lower wall thickness is 325 µm).

The standard bending test strip coated with an alcohol-based refractory coating was then placed on a furan resin mold (size 280) coated with an undiluted conventional zirconium-containing refractory coating (Zirkofluid 1219 from Hüttenes-Albertus GmbH). ×200×130 mm) and in this mold, cast iron around the standard bending test bars (casting temperature is about 1440°C; about 3.09 wt% carbon content, about 1.89 wt% silicon content, in each case The total mass of cast iron), so that the standard bending test strip is completely surrounded by the iron casting in each case, and experiences the maximum stress for the compressive load (applied by iron as the cast metal) during casting.

After the casting operation, the remaining residue of the standard bending test strip is removed from the iron casting by rotating the iron casting (so that the remaining residue of the standard bending test strip can be hollowed out from the iron casting produced by the standard bending test strip) The direction of the space opens downwards), and visually evaluates the unencapsulation behavior (except nuclear behavior) of the standard bending test strip. Here, the following observations are obtained:

The remaining residue of the standard bending test strip B-cold box (comparative group) can hardly be removed from the iron casting in the manner indicated above; it remains almost completely in the iron casting.

The remaining residues of the standard bending test strips B-V6 (produced by the method of the invention in the absence of a cross-linking step) and B-E6+ (produced by the method of the invention in the presence of a cross-linking step) can be extremely easy And almost completely removed from the iron casting in the manner indicated above. Almost no visible remaining residue remains in the iron casting.

From the above observation results, it can be seen that the hardened and molded parts produced by the method of the present invention (here: standard bending test strips B-V6 and B-E6+, indicating cores, replenishment ports, or molds) exhibit excellent de-nucleation or can Releasability, and therefore far superior to the comparative molded part (B-cold box) in this respect.

Instance 7 : Self-insulating supply port composition as a standard test sample of mold material mixture ( Standard bending test strip and standard test column ) Production The ingredients indicated in Table 5 below are used to produce the mold material mixture for the insulation supply port. The mold material mixture was produced in a manner similar to that indicated in Example 1 above.

Subsequently, the bending test strip was formed from the obtained and hardened mold material mixture in a manner similar to that of Example 2 above to obtain a standard bending test strip. In addition, by tamping and hardening in a manner similar to that described in Example 2 above, a standard test column (height: 50 mm, diameter: 50 mm) according to the VDG standard P38 was generated from the resulting mold material mixture as Hardened molded part (at 210°C, in a convection drying oven, for standard bending test strips and standard test columns using the mold material mixture F-E6+ (2), 30 minutes). In the case of the mold material mixture F-E6+ (2), the standard bending test strip or the standard test column produced as described above in each case corresponds to the hardened molded part (with a cross-linking step) in the sense of the present invention.

Subsequently, the obtained standard bending test strip "B-cold box" (comparative group) and the obtained standard bending test strip B-E6+ (2) (according to the method indicated in Example 3) The final strength produced by the present invention. The results of all corresponding measurements are reported in Table 5 below (the average of 3 measurements in each case).

The air permeability values of the standard bending test strip and the standard test column measured in each case and their weight are also reported in Table 5. Air permeability is a test value that gives information about the densification of the microstructure. Especially in the case of a replenishment port, this is a parameter that can give information about a satisfactory outflow of casting gas during casting operations. Table 5 : Composition of the mold material mixture used for the insulation supply port ingredient Mold material mixture F- cold box (2) F-E6+ (2) Expanded perlite [parts by weight] 100 100 Water-based PVAL mixture [parts by weight] 0 17.15 Aliphatic polyisocyanate [parts by weight] 0 1.45 Aqueous preparation of polyglucosamine [parts by weight] 0 11.4 Cold box activator 6324 [parts by weight] 9.0 0 Cold box gas resin 7241 [parts by weight] 9.0 0 The quality of standard test column [g] 47 41 Air permeability of standard test column 45 85 The bending strength of the bending test strip [N/cm ² ] (final strength) 350 300

The ingredients indicated in Table 5 "aqueous PVAL mixture", "aliphatic polyisocyanate", "aqueous preparation of polyglucosamine", "cold box activator 6324" and "cold box gas resin 7241" correspond to those in Example 1. The indicated ingredients.

From the results reported in Table 5 above, it can be seen that the insulating replenishment port composition produced by the method of the present invention has characteristics equivalent to those of the replenishment port composition produced by the cold box method known from the prior art.

Instance 8 : Casting using aluminum forming part By blowing in the nuclear injection machine, the mold material mixture "F-cold box (2)" is used in a manner known to those skilled in the art (gas treatment with the catalyst N,N-dimethylpropylamine). The insulation supply port composition produced in Example 7 produced an insulation supply port (closed at the bottom by a plate).

The insulating supply port composition having the mold material mixture "F-E6+ (2)" produced according to the present invention in Example 7 above was used in the same mold on the nuclear injection machine (such as the supply port composition "F-cold box (2) "In the case of "Insulation replenishment port for blowing injection." Hardening was carried out at 210°C for 30 minutes, with water being drawn in a drying oven (convection).

The insulation supply port produced by the mixture of the two mold materials used in the above-indicated manner was allowed to stand in a cold box combined sand mold, and cast with aluminum in each case to test its behavior under metal casting conditions. The other insulation supply ports produced in this way are left to stand in the loose sand and cast iron instead of non-aluminum in each case.

Obtain the following observations: When using the comparative mold material mixture F-cold box (2) (not by the method of the present invention) the insulation supply port produced by aluminum was used for casting, severe smoke formation was observed, and even when the casting supply was removed from the sand mold After the mouth, the severe smoke formation continued.

When the insulating supply port produced by the mold material mixture F-E6+ (2) (by the method of the present invention) was cast with aluminum, no smoke formation was observed. After casting, the insulation replenishment port produced according to the present invention showed significantly better unencapsulation behavior than the insulation replenishment port produced using the comparative mold material mixture F-cold box (2), that is, the insulation replenishment port produced according to the present invention The insulation supply port can be significantly easier to separate from the aluminum. The resulting aluminum casting exhibits a significantly cleaner surface (ie, no condensation product deposition) than the aluminum casting produced using the insulating replenishment port produced by the comparative mold material mixture F-cold box (2).

Instance 9 : Test casting of iron cube The mold material mixture indicated in Table 6 below is molded on the core injection machine in a manner known to those skilled in the art in each case to obtain an (insulated) supply port.

In the case of the replenishment port mixture "F-cold box (3)", hardening is carried out by gas treatment with the catalyst N,N-dimethylpropylamine in a manner known to those skilled in the art. In the case of the replenishment port mixture "F-water glass (2)", it is cured in a drying oven (convection) at 210°C for 25 minutes. In the case of the replenishment port composition "F-E6+ (3)", hardening to obtain a cross-linked hardened molded part is performed by heating in a drying oven (convection) at 210°C and removing water for 30 minutes. This produces the replenishment ports "Supply Port-Cold Box" and "Supply Port-Water Glass" that are not generated according to the present invention and the replenishment ports "Supply Port-B-E6+" generated according to the present invention. Table 6 : Composition of the mold material mixture used for the replenishment port ingredient Mold material mixture F- cold box (3) F- water glass (2) F-E6+ (3) Silica sand [parts by weight] 100 100 100 Water-based PVAL mixture [parts by weight] 0 0 3.43 Aliphatic polyisocyanate [parts by weight] 0 0 0.29 Aqueous preparation of polyglucosamine [parts by weight] 0 0 2.28 Cold box activator 6324 [parts by weight] 1.2 0 0 Cold box gas resin 7241 [parts by weight] 1.2 0 0 Sodium water glass adhesive 48/50 [parts by weight] 0 1.5 0

The ingredients indicated in Table 6 correspond to the ingredients indicated in Example 1 and their meanings in each case.

In each case, the practical usability of the above-mentioned replenishment port, especially the quality of the replenishment port, was tested by using it in the test casting of the iron cube (illustrative metal casting). For this purpose, at a casting temperature of 1400°C, the replenishment ports of the same size (that is, the same modulus in each case) are each used for iron (GGG40) with a modulus of 1.68 cm (that is, volume and Surface area ratio) of the cube sample casting. In order to evaluate the quality, those skilled in the field of casting technology will frequently use cubes with significantly higher modulus than the replenishment port in order to obtain the best possible information about solidification from experiments. The quality of the replenishment is evaluated by the depth of the recessed hole extending into the cube, where the recessed hole extends deeper into the cube (metal casting) indicating a poorer replenishing effect.

After casting and cooling to room temperature, the test cube produced as indicated above was sawn in the middle (half) to expose its section and evaluate the casting quality and the replenishment port function quality of the replenishment port used in each case. Visual evaluation of the cross-section of the test cube obtained by sawing together with the remaining recharge port made of iron visible on the top, the results are as follows:

When using a cold box combined with a replenishment port not produced in accordance with the present invention, significant crater formation extending into the metal casting occurred under the test conditions.

When the water glass combined with the replenishment port not produced according to the present invention is used, under the test conditions, the formation of obvious sinkholes extending deep into the metal casting occurs. The low quality of the water glass combined with the supply port under the test conditions can be attributed to the relatively high absorption of heat energy by the water glass binder (called its unfavorable "quenching behavior") and the casting produced by it. The metal solidifies relatively early.

On the other hand, when using the replenishment port "Replenishment Port-B-E6+" produced in accordance with the present invention, no sinkholes appear in the metal casting, except basically only at the upper end of the residual metal replenishment port.

Therefore, it can be concluded from the observation results indicated above that the replenishment port produced according to the present invention has a significantly better replenishment capacity than the conventional cold box combined or water glass combined replenishment port for comparison.

Instance 10 : Production of water-based adhesive system Use the ingredients indicated in Table 7 below to create an aqueous adhesive system.table 7 : Components of water-based adhesive system ingredient Water-based adhesive system WB-V6 WB-E6+ Water-based PVAL mixture [parts by weight] 60.00 57.14 Aliphatic polyisocyanate [parts by weight] 0 4.76 Aqueous preparation of polyglucosamine [parts by weight] 40.00 38.10

The ingredients indicated in Table 7 "aqueous PVAL mixture", "aliphatic polyisocyanate" and "aqueous preparation of polyglucosamine" correspond to the ingredients indicated in Example 1.

The water-based adhesive systems WB-V6 and WB-E6+ are water-based adhesive systems to be used according to the present invention. The water-based adhesive system WB-E6+ corresponds to the above-mentioned water-based mixture as the second adhesive system.

Claims (17)

A method of i) for producing metal castings and/or ii) for producing hardened molded parts for casting metal castings, the hardened molded parts selected from the group consisting of molds, cores and replenishment ports, the method includes the following Step: V1) Production of a mold material mixture containing the following components: a) at least one base mold material, b) one or more aliphatic polymers, which in each case contain the hydroxyl-containing structural unit of formula I -CH ₂ -CH( OH)- (I), c) One or more ingredients selected from the group consisting of the following as curing agent components: c1) One or more biopolymers selected from the group consisting of poly-D-glucosamine and c2 ) One or more polyisocyanates as crosslinking agents for the hydroxyl groups of the one or more aliphatic polymers; and d) water; V2) molding the mold material mixture, and then V3) hardening the mold material mixture in one or more steps Mold material mixture or unhardened downstream products formed therefrom, resulting in a hardened molded part. The method of claim 1, wherein the mold material mixture is produced by thoroughly mixing the components a) to d) with each other in step V1). Such as the method of claim 1, among them The mold material mixture contains the component c1) as the curing agent component c), one or more biopolymers selected from the group consisting of poly-D-glucosamine, And/or The hardening covered in step V3) V31) Precipitating at least a part of the one or more biopolymers, Preferably by increasing the pH value of the aqueous part of the molding material mixture, especially by contacting with an alkaline gaseous compound, preferably by treating with an alkaline gaseous compound gas, and very preferably by treating with a gaseous amine, So as to produce a molded part with good green strength; And/or V32) Treat the molding material mixture and/or the unhardened downstream products formed therefrom and/or the molding part with good green strength, By heating the molding material mixture and/or the unhardened downstream product formed therefrom and/or the molding part with good green strength to preferably within the range of 100°C to 300°C, particularly preferably The ground is within the range of 150°C to 250°C and extremely well within the temperature range of 180°C to 230°C, And/or By removing water from the molding material mixture and/or from the unhardened downstream product formed therefrom and/or removing water from the molded part with good green strength. Such as the method of claim 1, among them The mold material mixture contains the component c2) as the curing agent component c), one or more polyisocyanates, preferably aliphatic polyisocyanates, And/or The hardening covered in step V3) V32) Treat the molding material mixture and/or the downstream products formed from it and/or the molding parts with good green strength, Preferably, By heating the molding material mixture and/or the downstream products formed therefrom and/or the molding part with good green strength to preferably within the range of 100°C to 300°C, particularly preferably Temperature in the range of 150°C to 250°C and excellently in the range of 180°C to 230°C, And/or By removing water from the molding material mixture and/or from the unhardened downstream product formed therefrom and/or removing water from the molded part with good green strength, And preferably, V33) In the molding material mixture and/or the downstream products formed therefrom and/or the molding part with good green strength, the hydroxyl groups of the one or more aliphatic polymers of formula I are combined with the The isocyanate groups of polyisocyanate are cross-linked, Thereby, a cross-linked molded part is produced as a hardened molded part. The method of claim 1, wherein the aliphatic polymers containing the structural units of formula I containing hydroxyl groups are used Can be produced by at least partial hydrolysis of polyvinyl acetate; And/or Selected from the group consisting of: polyvinyl alcohol, polyvinyl acetate and their mixtures And/or Except for the one or more biopolymers selected from the group consisting of poly-D-glucosamine used as component c1) in the mold material mixture, the total mass of all organic polymers containing hydroxyl groups used Of ≥75% by weight, preferably ≥90% by weight, particularly preferably ≥98% by weight, And/or Contains one or more polyvinyl alcohols, Among them, all the polyvinyl alcohols used are better Preferably, it is determined by the method indicated in paragraphs [0029] to [0034] of the document DE 10 2007 026 166 A1, and the degree of hydrolysis is> 50 mol%, And it is better to measure by the method of DIN EN ISO 15023-02 2017-02 draft Annex D, especially preferably the degree of hydrolysis is in the range of 70 mol% to 100 mol%, and very preferably in the range of 80 mol% to 100 mol% Within %, And/or In each case, the dynamic viscosity is in the range of 0.1 to 30 mPažs as measured by the 4% strength (w/w) aqueous solution of all the polyvinyl alcohol used at 20°C according to DIN 53015:2001-02. It is preferably in the range of 1.0 to 15 mPažs, particularly preferably in the range of 2.0 to 10 mPažs; And/or The total mass of the all aliphatic polymers containing the hydroxyl-containing structural unit of formula I used in the mold material mixture is ≥75% by weight, preferably ≥90% by weight, particularly preferably ≥98% by weight. According to the method of claim 1, wherein one or more of the biopolymer or a plurality of biopolymers selected from the group consisting of poly-D-glucosamine comprises polyglucosamine, wherein the polyglucosamine is preferably Measured by means of ¹ H NMR spectroscopy, the degree of deacetylation is >70 mol%, preferably >75 mol% and especially preferably >80 mol%, and/or in each case according to DIN 53015:2001 -02 Measured with a 1% strength (w/w) solution of the polyglucosamine in 1% strength (w/w) acetic acid at 20°C, the dynamic viscosity is> 500 mPažs, preferably> 600 mPažs, especially preferably ≥ 700 mPažs; and/or the total mass of the used aliphatic polymers containing hydroxyl-containing structural units of formula I and the total mass of the used biopolymers selected from the group consisting of poly-D-glucosamine , The ratio of the sum of the total mass of the base mold material used is in the range of 0.2:100 to 13:100, preferably in the range of 0.3:100 to 10:100, especially preferably in the range of 0.5:100 to 9:100 Within range. The method of claim 1, wherein the one or more polyisocyanates comprise one or more water-dispersible polyisocyanates. The method of claim 1, wherein the one or more polyisocyanates comprise aliphatic polyisocyanates, Among them, preferably, One or more or all of the aliphatic polyisocyanate or the plurality of aliphatic polyisocyanates are nonionic or ionic hydrophilized, And/or One or more or all of the aliphatic polyisocyanate or the plurality of aliphatic polyisocyanates contain polyether groups or sulfonate groups, And/or The aliphatic polyisocyanate or one or more or all of the aliphatic polyisocyanates contain polyether groups, and additionally urethane and/or allophanate groups, And/or The aliphatic polyisocyanate or one or more or all of the aliphatic polyisocyanates include one or more 2,4,6-trilateral oxytriazinyl groups, and preferably polyether or sulfonate groups Acid ester group, preferably polyether group, And/or The aliphatic polyisocyanate or one or more or all of the aliphatic polyisocyanates include one or more 2,4,6-trilateral oxytriazinyl groups and polyether groups, and additional amino groups Formate and/or allophanate groups, preferably urethane groups, And/or The one or more aliphatic polyisocyanates used constitute ≥50% by weight, preferably ≥75% by weight, particularly preferably ≥90% by weight of all the one or more polyisocyanates used in the molding material mixture, and Excellent ≥98% by weight. Such as the method of claim 1, among them The total mass of the used aliphatic polymers containing hydroxyl-containing structural units of formula I and The total mass of the biopolymer used selected from the group consisting of poly-D-glucosamine Sum of versus The total mass of the preferred aliphatic polyisocyanate used as a crosslinking agent The ratio It is in the range of 1:1 to 10:1, preferably in the range of 1.5:1 to 7.5:1, and particularly preferably in the range of 2:1 to 5:1. Such as the method of claim 1, Among them, the basic mold material includes: One or more particulate refractory solids selected from the group consisting of: Oxides, silicates, and carbides, in each case, contain one or more elements from the group consisting of Si, Al, Zr, Ti, Mg, Fe, and Ca, Mixed oxides, mixed carbides and mixed nitrides, in each case contain one or more elements from the group consisting of Si, Al, Zr, Ti, Mg, Fe and Ca, and graphite And/or One or more particulate lightweight fillers, which are preferably selected from the group consisting of: Core-shell particles, which preferably include a glass core and a refractory shell, and particularly preferably have a bulk density in the range of 470-500 g/l; Refractory composite particles; Sphere Perlite, preferably expanded perlite; Closed-cell microspheres made of expanded perlite; Rice husk ash Expanded glass, Hollow glass ball and The hollow ceramic ball is preferably a hollow α-alumina ball. Such as the method of any one of claims 1 to 10, wherein the method for producing metal castings includes the following additional steps: V4) The hardened forming part, preferably obtained after step V32) and preferably additionally step V33), is brought into contact with the cast metal for producing metal castings, wherein the cast metal is preferably in contact with the hardened forming part Solidifies on contact, Among them, preferably, The cast metal is selected from the group consisting of aluminum, magnesium, tin, zinc and their alloys And/or The temperature of the cast metal during casting does not exceed 900°C; This produces metal castings. A hardened molded part selected from the group consisting of a mold, a core and a replenishment port for casting metal castings, which can preferably be produced by a method such as any one of claims 1 to 11, the hardened molded part includes a) at least one base mold material, b) one or more aliphatic polymers, which contain a hydroxyl-containing structural unit of formula I -CH ₂ -CH(OH)- (I), and c) as one of the curing agent components Or more ingredients selected from the group consisting of: c1) one or more preferably precipitated biopolymers selected from the group consisting of poly-D-glucosamine, and c2) one or more preferably aliphatic polyisocyanates , Wherein the hydroxyl groups of the aliphatic polymers containing hydroxyl-containing structural units of formula I are preferably at least partially hardened, preferably by combining with the isocyanate groups of the one or more polyisocyanates used It exists in the form of cross-linked, cross-linked and hardened adhesive. For example, the hardened molded part with good green strength of claim 12, which contains the component c1) as the curing agent component c), one or more precipitated organisms selected from the group consisting of poly-D-glucosamine The polymer preferably contains polyglucosamine. For example, the hardened molding part of claim 12 or 13, which contains the component c2) as the curing agent component c), one or more preferred aliphatic polyisocyanates, wherein the used ones contain the structure of formula I containing hydroxyl The hydroxyl groups of the aliphatic polymer of the unit are at least partially present in the form of a hardened adhesive that is crosslinked by crosslinking with the isocyanate groups of the one or more polyisocyanates used. A mold material mixture, which contains the following components: a) at least one base mold material, b) one or more aliphatic polymers, which contain a hydroxyl-containing structural unit of formula I -CH ₂ -CH(OH)- (I), c) One or two components selected from the group consisting of: one or more biopolymers selected from the group consisting of poly-D-glucosamine and as the one or more aliphatic polymers One or more of the crosslinking agents of the hydroxyl group are preferably water-dispersible and/or aliphatic polyisocyanates; and d) water. The use of an aliphatic polymer, the aliphatic polymer contains a hydroxyl-containing structural unit of formula I -CH ₂ -CH(OH)- (I) which has been crosslinked by one or more aliphatic polyisocyanates, preferably The polyvinyl alcohol crosslinked in this way is used as a binder for the molding part selected from the group consisting of molds, cores, and replenishment ports for casting metal castings. A use of a biopolymer selected from the group consisting of poly-D-glucosamine, preferably polyglucosamine, which is used as a binder or binder component in the foundry industry to produce selected from molds, cores and supplies The hardened molded part of the mouth composition group is preferably a molded part with good green strength.