Binder components for raw material compounds used in molding and sintering methods, particulate raw material compounds, and molding and sintering methods.

Abstract

A binder component for a raw compound for use in a molding and sintering method, comprising bi) 3-70% by volume of at least one first thermoplastic material and / or wax-based material, and b-ii) 30-97% by volume of at least one second thermoplastic material and / or wax-based material, or plasticized thermoplastic material and / or wax-based material, based on the total volume of the binder component b). The first thermoplastic material and / or wax-based material and the second thermoplastic material and / or wax-based material differ in at least one property selected from (1) solubility in a solvent; (2) decomposition induced by heat and / or reactants; and (3) volatility. The first thermoplastic material and / or wax-based material is less soluble, less decomposable, or less volatile than the second thermoplastic material and / or wax-based material. T cross is T P [wherein, T P is the DSC melting peak temperature of binder component b), T cross is the temperature at the intersection of the storage modulus G' curve and the loss modulus G'' curve in the dynamic viscoelasticity measurement of the binder component b). Particulate raw material compounds containing binder components and sinterable non-organic particles are used in additive manufacturing, injection molding, pressing, or casting.

Description

[Technical Field]

[0001] The present invention relates to a binder component for a raw material compound for use in a molding and sintering method, a particulate raw material compound comprising sinterable non-organic particles and a binder component, and a method comprising the steps of fusing a plurality of particulate raw material compounds and debinding them. [Background technology]

[0002] Methods such as additive manufacturing, powder injection molding, or press working can quickly and efficiently produce customized parts. Additive manufacturing involves adding material together (usually layer by layer), such as by fusing powder particles together. Generally, a typical additive manufacturing method involves a step of forming the first layer of material, and then a step of continuously adding further layers of material, with each new layer of material being added on top of the previously formed layers until the entire three-dimensional structure (3D object) is materialized.

[0003] Powder injection molding involves melting a material and injecting it into a mold to form an object. In particular, low-pressure powder injection molding (LPIM) requires appropriate processing temperatures and pressures for these steps.

[0004] In Laser Beam Powder Bed Fusion (LB-PBF), binder-free metal powder is sintered by scanning with a high-power laser beam. To eliminate the need for a high-power laser, binder-coated metal powder was formed by additive manufacturing. In a post-processing step, the binder is removed and the metal powder is sintered.

[0005] All of these new methods require a clearly defined raw material compound containing a sinterable material and a binder. In recent years, a variety of such raw material compounds have been documented in the literature. Patent Document 1 describes a powder for use in a selective laser sintering method, comprising a (metallic) substrate coated with a polymer binder. The binder includes, for example, an amorphous copolymer of butyl methacrylate and styrene, or methyl methacrylate and butyl methacrylate. Optionally, the binder may also contain a plasticizer, but this will not be described in detail.

[0006] Patent Document 2 describes an element consisting of powder particles containing metal particles such as Fe, Co, Ni, W, Mo, or metal carbides. The particles are bonded together via a polyamide and a plasticizer / wax mixture, but this will not be described in detail.

[0007] Patent Document 3 describes a low-pressure powder injection molding machine, a kit, and a method for it. Low-pressure powder injection molding (LPIM) is a variation of conventional high-pressure powder injection molding (HPIM), and recent advances in raw material formulation have created new opportunities to manufacture more complex shapes at a cost-effective rate, whether in large or small production volumes. Typically, a pneumatic molding machine is used to fill the mold cavity with a mixture of powder and binder.

[0008] Recently, Tafti et al. described the effect of thermal debinding conditions on the sinter density of iron parts molded by low-pressure powder injection molding (see Non-Patent Literature 1). Therefore, they injected a low-viscosity raw material into a rectangular mold cavity, thermal debinding was performed at three different debinding temperatures, and then sintered. Increasing the debinding temperature from 600°C to 850°C reduced the number of fine particles, resulting in a (sintered) density of 6.2 to 5.1 g / cm³. 3 The average pore diameter decreased (from 9 to 14 μm), and consequently, the pore circularity also decreased (from 67 to 59%).

[0009] According to Tafti et al. (see above), in the conventional HPIM method, the binder, which consists of a blend of low-molecular-weight polymers and high-molecular-weight polymers (also called the first and second binders, respectively), is removed in two stages. In the first stage, depending on the binder system and the properties of the powder, the first binder is extracted using either a solvent, a supercritical fluid such as supercritical carbon dioxide, or a catalyst such as high-concentration nitric acid. In the second stage, the second binder, which acts as a framework to maintain the shape, is removed during the final burnout cycle before the sintering process.

[0010] Typically, LPIMs use multi-component binders that do not contain high-melting-point skeletal polymers. For example, such multi-component binders may include wax-based carriers, surfactants, and thickeners.

[0011] However, in the absence of a skeletal binder, all binder components are removed in a single step during debinding (e.g., during hot wick debinding), making one of the main challenges encountered in the LPIM method shape retention and insufficient strength of the brown part. The hot wick debinding process extracts the binder from the green part by relying on capillary extraction of the liquid binder. This approach consists of embedding the injected part in a wicking powder bed (e.g., graphite, alumina, or other inert powder) and heating it to a pre-sintering temperature (e.g., the binder softening temperature) in a protective atmosphere as needed. The powder bed acts as a wicking medium, drawing the molten binder from the heated part by capillary flow. It acts as a physical support, maintaining the fragile debinding part until the powder particles are pre-sintered. In hot wick debinding, careful selection of key parameters such as pore size of the wicking medium, debinding temperature, heating rate, protective atmosphere, or pre-sintering temperature is necessary to ensure proper binder extraction while avoiding undesirable drawbacks such as stress, strain, defects, and chemical reactions. However, the use of fine powders can lead to contamination of green parts, which may require further cleaning.

[0012] For example, Patent Document 4 discloses a composite material containing tungsten and bronze. To form a homogeneous mixture, tungsten and bronze powders (non-organic particles) are mixed with an organic binder. The organic binder is usually a thermoplastic binder, wax, or wax mixture. Preferred binders include low molecular weight waxes or wax mixtures that melt at temperatures of room temperature to about 120°C, more preferably about 50°C to 90°C, and even more preferably about 55°C to 65°C. For example, the wax may be paraffin wax, microcrystalline wax, polybutene wax, polyethylene wax, carnauba wax, or a mixture of two or more of these. The thermal debindering step involves heating the molded part in a furnace to a temperature at which the binder is rapidly transformed into a gaseous product by thermal decomposition and extruded by a flowing protective atmosphere. Once the part is heated, the binder melts. A wicking powder, such as a powder containing alumina, can be used to create a capillary force gradient that draws the binder out of the part.

[0013] Patent Document 5 describes a thermoplastic binder comprising metal and / or ceramic powder, a thermoplastic polymer, and at least one plasticizer, as well as fine fibers (filaments) optionally containing additives. Suitable thermoplastic polymers described therein are, for example, polyurethane, polyamide, polyvinylpyrrolidone, polyacrylate, or polyolefin, and suitable plasticizers are selected from aromatic or heteroaromatic carboxylic acid esters such as hydroxybenzoic acid esters.

[0014] Patent Document 5 discloses a fine fiber (filament) suitable for use in a 3D printing apparatus, which comprises or consists of a metal powder and / or ceramic powder, a thermoplastic polymer and a thermoplastic binder containing at least one plasticizer, and optionally additives. Furthermore, a method for producing a molded body containing the above fine fiber is disclosed. The molded body is obtained by printing a molded unsintered body using the fine fiber, removing at least a portion of the plasticizer, and sintering.

[0015] In recent years, methods for manufacturing metal and / or glass and / or ceramic parts by additive manufacturing have been described. Patent Document 6 discloses a method for additive manufacturing metal and / or glass and / or ceramic parts. The raw material compound particles are prepared from base material particles and at least two phases of binder. The raw material compound particles are selectively melted in layers by electromagnetic radiation, and molded parts are additively manufactured. The molded parts are recovered from the unmelted mixture, and then at least two phases of binder are continuously removed. Finally, the debindered molded parts are sintered.

[0016] However, various factors during the printing process can compromise the dimensional accuracy of a part compared to the target data defining the part. For example, it is often difficult to manufacture parts with sharp, precise edges and low porosity (unsintered). Furthermore, improvements to the molding process should not come at the expense of or degrade the binder removal process. [Prior art documents] [Patent Documents]

[0017] [Patent Document 1] WO 95 / 30503 [Patent Document 2] DE 19648926 C1 [Patent Document 3] US 20190134712 A1 [Patent Document 4] US 2003 / 0161751 A1 [Patent Document 5] WO 2016 / 004985 A1 [Patent Document 6] WO 2018 / 197082 [Non-patent literature]

[0018] [Non-Patent Document 1] Tafti et al., Metals 2021,11,264-276 [Overview of the project]

[0019] Therefore, an object of the present invention is to provide a binder component for a raw material compound that enables high print dimensional accuracy and a simple and economical method of de-binding in a method using a raw material compound containing a binder component.

[0020] The present invention relates to a binder component for raw material compounds used in molding and sintering methods. Based on the total volume of the binder component (b), bi) 3 to 70 volume percent of at least one first thermoplastic material and / or wax-based material, b-ii) 30 to 97 volume percent of at least one second thermoplastic material and / or wax-based material, or a plasticized thermoplastic material and / or wax-based material, Includes; The first thermoplastic material and / or wax-based material and the second thermoplastic material and / or wax-based material differ in at least one property, which is selected from the following: (1) Solubility in solvents (2) Decomposition induced by heat and / or reactants, (3) Volatility; The first thermoplastic material and / or wax-based material has lower solubility, lower decomposition, or lower volatility than the second thermoplastic material and / or wax-based material; T crossis, T P Compared to that, it is high within the range of not exceeding 60K (T P This is the DSC melting peak temperature of binder component (b), and T cross (where is the temperature at the intersection of the storage modulus G' curve and the loss modulus G'' curve in the dynamic viscoelastic measurement of the binder component (b)).

[0021] Hereinafter, the expression "(plasticizable) thermoplastic materials and / or wax-based materials" is intended to encompass both "thermoplastic materials and / or wax-based materials" and "plasticizable thermoplastic materials and / or wax-based materials."

[0022] The present invention also relates to particulate raw material compounds for use in molding and sintering methods, and includes the following: a) Sinterable non-organic particles dispersed throughout the particulate raw material compound (at least 80% of the particles have a maximum particle size in the range of 100 nm to 200 μm A max (Having a particle size distribution that includes) and b) Binder component (b).

[0023] The present invention also relates to a method comprising the steps of fusing a plurality of particulate raw material compounds and a binder removal step.

[0024] The following description of preferred embodiments refers to binder components, particulate raw material compounds, and methods unless otherwise specified.

[0025] Generally, the molding process of additive manufacturing typically involves providing a powder bed of particulate material compounds in a construction space that is heated to a high temperature, for example, 50-60°C. The particulate material compounds in the powder bed can absorb energy from energy rays from a radiation source, such as a laser beam, resulting in an increase in the temperature of localized areas of the powder material. This localized temperature increase can selectively densify or melt the particulate material compounds, causing them to bond together in a predetermined manner.

[0026] The melting behavior of the binder has been shown to strongly affect printing accuracy. While strong bonding between particulate material compounds is desirable within localized areas, bonding to neighboring or adjacent particles should be avoided. Material compounds with unoptimized binder components can dissipate heat to adjacent particles, causing them to soften and adhere to the outer surface of the part, resulting in reduced surface resolution.

[0027] In powder injection molding, particulate raw materials are melted by a heated barrel and / or screw and injected into the mold by a plunger, pressure, or gravity. Similarly, melting behavior has been shown to strongly influence processing parameters in powder injection molding. Due to the low viscosity of the raw material compound, the size of the injection molding machine and the overall mold can be reduced, both significantly smaller than those required for HPIM. The cost reduction associated with smaller molds provides an opportunity to manufacture complex parts in a cost-effective manner, regardless of whether the production volume is small or large. Furthermore, due to the ease of molding and the high fluidity of the raw material compound, it is possible to manufacture larger parts than with HPIM.

[0028] The binder component of the present invention exhibits a very limited temperature transition from solid or semi-solid to fluid, resulting in minimal impact on adjacent raw material compound particles during 3D printing. As a result, the irradiated raw material compound particles are converted from solid to fluid at relatively low temperatures, allowing for the formation of dense green parts without affecting adjacent raw material compounds. This very limited temperature transition from solid or semi-solid to fluid is described in detail below, as follows: P and T cross This is reflected in the small difference between them.

[0029] Typically, differential scanning calorimetry (DSC) can measure the physical properties of materials, such as glass transition temperature, melting temperature, and enthalpy of melting.

[0030] The melting process results in an endothermic peak in the DSC curve, and the melting temperature is the melting peak temperature T in the DSC curve at which the rate of change of the endothermic heat flow is maximum P is referred to.

[0031] The DSC curve may include a single melting peak. Alternatively, the DSC curve may include several melting peaks, i.e., several local maxima. For the purposes of this specification, the melting peak temperature T P is defined as the temperature of the global maximum. The binder component (b) preferably exhibits a single melting peak.

[0032] In one embodiment, the binder component (b) has a melting peak temperature T in the range of less than 180 °C, preferably 10 °C to 180 °C, more preferably 20 °C to 160 °C, most preferably 30 °C to 140 °C, particularly 35 °C to 120 °C, particularly 40 °C to 100 °C, particularly 45 °C to 90 °C, particularly 50 °C to 85 °C P is shown. The melting peak temperatures T in these ranges P enable selective densification or melting with as little additional energy (e.g., laser energy) as possible and a low-energy laser source can be conveniently used.

[0033] In this specification, T P is determined by the second heating after the first heating / cooling cycle in accordance with DIN EN ISO 11357-3. For this purpose, the sample is heated at a first heating gradient from -20 °C to a temperature 20 K higher than the completion of all thermal events, then cooled to -20 °C, and finally reheated at a second heating gradient from -20 °C to a temperature 20 K higher than the completion of all thermal events. The heating and cooling rates for each are 10 K / min. The "thermal events" for the purposes of this specification mean thermal events other than decomposition, in other words, essentially reversible thermal events.

[0034] Usually, the dynamic viscoelastic properties including the storage modulus G' and the loss modulus G'' of a material can be determined by dynamic viscoelastic measurement.

[0035] The storage modulus G' represents the elastic modulus of a material. It is proportional to the proportion of deformation energy stored in the material and recovered from the material after stress relief.

[0036] The loss modulus G'' represents the viscous portion of the material. It corresponds to the rate of energy loss that is converted into heat due to internal friction.

[0037] T cross T is the temperature at which the storage modulus G' curve and the loss modulus G'' curve intersect in the dynamic viscoelasticity measurement of the binder component. This temperature is also called the "crossover" temperature in the literature and refers to the state of the material where the transition from the molten state to the viscous state occurs. If the G' curve and G'' curve intersect multiple times, T cross This is the intersection point at the highest temperature. Those skilled in the art will understand that the term "highest temperature" refers to the highest temperature lower than the temperature at which decomposition occurs.

[0038] The sample of binder component (b) is subjected to dynamic viscoelasticity measurement.

[0039] In principle, T cross This can be determined in the heating or cooling process. Dynamic effects such as supercooling or interrupted thermal transitions are considered in the T cross This may interfere with the measurement. To eliminate the effects of dynamics, T in the heating or cooling process. cross It may be desirable to measure T during heating. cross and T measured during cooling cross If they are different, T cross Use the higher value.

[0040] Due to non-equilibrium transitions that can occur during binder measurements, measuring the raw material compound may yield more accurate results in individual cases. Since non-organic particles (a) may act as crystallization nuclei and reduce the diffusion process, kinetic effects are less likely to occur when measuring the raw material compound.

[0041] For example, the storage modulus G curve and the loss modulus G'' curve are obtained at temperatures lower than the melting temperature (e.g., T P This is recorded by dynamic viscoelasticity measurements while heating the material from a temperature 20K lower to the temperature at which the material completely melts.

[0042] With cooling and heating rates set at 1 K / min, the mixture was first cooled from 110°C to 60°C, and then heated to 110°C.

[0043] In the context of this patent application, dynamic viscoelastic measurements for determining the storage modulus and loss modulus are performed in accordance with DIN 53019-4:2016-10. The measurements are appropriately performed using a plate-to-plate configuration with a diameter of 40 mm and a vibration mode at a frequency of 1 Hz. The measurement gap can be 0.15 mm.

[0044] To perform the measurement, the temperature at which the sample of binder component (b) completely liquefies, i.e., the estimated T of binder component (b), cross The shape is heated to a temperature exceeding approximately 20K, and the sample is placed on a plate below the high temperature. The cooling and heating rates are both 1K / min, and first the T of the binder component (b) is measured. cross The mixture is cooled from a temperature of over 20K to a temperature about 10K lower than the first intersection temperature, and then heated to a temperature of over 20K, which is the melting point of the binder component (b).

[0045] Under a cooling gradient, the measurement begins in a deformation control mode with a constant deformation γ = 0.1%. After reaching the trigger point, the measurement switches to a shear stress control mode with a constant shear stress (σ = 100 Pa for binders, σ = 700 Pa for raw material compounds).

[0046] Under a heating gradient, measurements are initiated in a shear stress control mode with a constant shear stress σ = 300 Pa. After reaching the trigger point, the measurement switches to a deformation control mode with a constant deformation γ = 0.1%. The trigger point is located in the transition zone between the solid and liquid states. Between these two states, the shear modulus changes significantly, requiring various control modes depending on the measurement needs.

[0047] During heating or cooling gradients, the sample undergoes a phase transformation, requiring a change in the measurement mode to remain within the linear viscoelastic range. For example, during a cooling gradient, the sample changes from a liquid to a hard state. The deformation in the liquid state must not be too large; if too large, the sample is no longer within the linear viscoelastic range. When a liquid is subjected to a specific deformation, releasing the applied force or stress causes the liquid to return to a completely new shape or position. Since the sample reaches the selected deformation in the liquid state, the measurement at this stage is deformation-controlled. In the hard state, deformation is not achieved, and the rheometer torque reaches its limit. Therefore, it is necessary to switch the measurement mode to shear stress control mode. The switch from deformation control mode to shear stress control mode is set by a trigger point. The trigger point is located in the transition area between the solid and liquid states. Between the two states, the shear modulus changes significantly, requiring various control modes depending on the measurement needs. The trigger point can be any specific point or reference that enables a change in the measurement mode within the linear viscoelastic range. The same applies to heating gradients.

[0048] According to the present invention, the binder component is T P Compared to T cross The condition is met that it is high within a range not exceeding 60K, preferably not exceeding 50K, more preferably not exceeding 45K, most preferably not exceeding 40K, and particularly not exceeding 35K. cross is T P This also includes situations that are even lower than this.

[0049] In one embodiment, binder component (b) is T init and [T P This indicates that the percentage of total enthalpy of melting measured by DSC between [+25K] is at least 94%, preferably at least 95%, more preferably at least 96%, most preferably at least 97%, particularly at least 98%, and particularly at least 99%. initis the initial melting temperature. The term "total enthalpy of melting" refers to the sum of endothermic DSC peaks that are 10°C to 20K higher than the completion of all thermal events, for example, in the range of 10°C to 200°C. The enthalpy of melting is usually reported as J / g and can be derived from the region enclosed by the endothermic DSC peak curve and the baseline.

[0050] For evaluation, the curved portion after complete melting was rotated horizontally. The baseline was drawn horizontally from the edge of the thermogram. Initial melting temperature (T init ) is T P The first intersection between the baseline and the thermogram at temperatures below T is the initial melting temperature of the binder component (b). P This represents the temperature at the maximum peak height.

[0051] A sample of the binder component (b) without sinterable non-organic particles (a), or a sample of the raw material compound with binder component (b) containing sinterable non-organic particles (a), is subjected to DSC. Since the sinterable non-organic particles (a) do not exhibit a phase transition within the temperature range of the DSC measurement, the overall shape of the DSC curve and the melting peak temperature remain essentially unchanged. The measurement of a sample containing both binder component (b) and sinterable non-organic particles (a) results in a different absolute peak area compared to the measurement of a sample containing only binder component (b). This is due to the "dilution" of the sample by the sinterable non-organic particles (a). However, since the ratio is expressed as a percentage, the results are essentially the same.

[0052] According to the present invention, the first thermoplastic material and / or wax-based material (bi) and the second thermoplastic material and / or wax-based material (b-ii) differ in at least one property selected from the following: (1) Preferably, alcohols such as ethanol or propanol; aromatic compounds such as benzene, toluene or xylene; esters such as ethyl acetate; ethers such as diethyl ether or tetrahydrofuran; ketones such as acetone; alkanes such as hexane or heptane; halogenated hydrocarbons such as n-propyl bromide, trichloroethylene, perchloroethylene, n-methylpyrrolidine; and solvents, water, and supercritical gases selected from mixtures thereof; and, (2) Decomposition induced by heat and / or reactants, preferably nitric acid; (3) Volatility by evaporation induced by temperature and / or reduced pressure, for example. Furthermore, the first thermoplastic material and / or wax-based material (bi) has lower solubility, lower decomposition, or lower volatility than the second thermoplastic material and / or wax-based material (b-ii).

[0053] The binder component (b) comprises 3 to 70 volume%, preferably 5 to 60 volume%, more preferably 7 to 50 volume%, most preferably 10 to 40 volume%, particularly 12 to 35 volume%, particularly 15 to 30 volume%, of a first thermoplastic material and / or wax-based material (bi), based on the total volume of the binder component (b).

[0054] Furthermore, the binder component (b) comprises 30 to 97 volume%, preferably 40 to 95 volume%, more preferably 50 to 93 volume%, most preferably 60 to 90 volume%, particularly 65 to 88 volume%, and particularly 70 to 85 volume%, of a second (plasticizing) thermoplastic and / or wax-based material (b-ii), based on the total volume of the binder component (b).

[0055] A variety of solubility, decomposition properties, or volatility enable selective debinding. In a selective debinding process, one binder component (in the context of this patent application, the second thermoplastic material and / or wax-based material (b-ii)) is removed while another binder component (the first thermoplastic material and / or wax-based material (bi)) remains in the manufactured part, together holding sinterable non-organic particles. Such debinding processes, such as solvent debinding, thermal debinding, and chemical debinding, are known in themselves.

[0056] The present invention uses partial debinding agents such as thermal debinding agents, solvent debinding agents, or chemical debinding agents, thereby avoiding the drawbacks associated with methods that rely on a wicking process.

[0057] In embodiments particularly suitable for small parts, thermal debindering can be performed without the need for a wicking process. In such a wicking process, the entire amount of binder softens over a narrow temperature range, requiring the part to be supported with wicking powder to prevent shape loss or distortion. This makes the process time-consuming and limits the design freedom of the part. Furthermore, the use of fine powder may contaminate the green part, potentially requiring further cleaning. The method according to the present invention involves gradually removing a second thermoplastic material and / or wax-based material (b-ii) from the part by decomposition and / or evaporation, with minimal impact on the first thermoplastic material and / or wax-based material (bi).

[0058] In one embodiment, the drawbacks associated with processes that rely solely on thermal debinding are also avoided, especially in large parts. During thermal debinding of a second thermoplastic material and / or wax-based material, as the temperature rises, the amount of binder evaporating from the entire mass of binder increases. If the binder portion evaporates rapidly without a reliable exit path, the part may break and lose its integrity. Therefore, to prevent the part from bursting, the rate of binder evaporation must be extremely slow, and the rate of degradation must be kept low. For this reason, thermal debinding of a second thermoplastic material and / or wax-based material is a difficult and time-consuming method, especially in the case of large parts. The method according to the present invention involves gradually removing the second thermoplastic material and / or wax-based material from the outside to the center of the part in a manner that minimizes the impact on the first thermoplastic material and / or wax-based material (i.e., by solvent debinding and chemical debinding).

[0059] Preferably, in the solvent-removal binder step, one binder component can be selectively removed from the green part by means of dissolving the binder component in the solvent, while a second binder component remains in the green part. Therefore, the binder components need to have different molecular weights and polarities, for example, in order to exhibit different solubility in the solvent.

[0060] Any polymer or wax may be very soluble in one solvent, such as a nonpolar solvent, but poorly soluble or insoluble in another, such as a more polar solvent. Therefore, whether a particular polymer or wax is eligible as a (bi) or (b-ii) material depends on the solvent used in the debindering process. Changing the solvent, for example from a polar solvent to a less polar or nonpolar solvent, or vice versa, may reverse the classification of the binder component as (bi) or (b-ii).

[0061] For example, when solvent debinding is performed using acetone as the solvent, the material remaining in the debinding component (first thermoplastic material and / or wax-based material (bi)) can be a polymer or wax that is poorly soluble or insoluble in acetone, while the binder component that is removed (second thermoplastic material and / or wax-based material (b-ii)) can be a polymer or wax that is soluble in acetone.

[0062] In one embodiment, the solubility of the first thermoplastic material and / or wax-based material (bi) is less than 0.1 g, preferably less than 0.05 g, more preferably less than 0.01 g, most preferably less than 0.005 g, and is particularly insoluble in the solvent. The solubility of the second thermoplastic material and / or wax-based material (b-ii) is in the range of 0.1 g to 500 g, preferably 0.5 g to 300 g, more preferably 1 g to 200 g, most preferably 2 g to 175 g, particularly 3 g to 150 g, and particularly 5 g to 100 g, in 100 g of solvent at a predetermined temperature. The predetermined temperature is 10°C to [T P The temperature can be in the range of -5°K, preferably 20°C to 80°C, more preferably 30°C to 70°C, most preferably 35°C to 65°C, and particularly 40°C to 60°C.

[0063] The chemical debinding process (also called "catalytic debinding") is described, for example, in DE 102005027216 A1. For this purpose, the molded article to be debinding is placed in a debinding furnace, where it is heated to a suitable processing temperature. Subsequently, a process gas containing a reactant (such as nitric acid) is introduced into the furnace. By bringing the molded part containing the binder into contact with the high-temperature reactant, the binder components can be burned off from the molded part. Depending on their chemical stability with respect to the reactants, one or more binder components may remain in the molded article.

[0064] In one embodiment, the first thermoplastic material and / or wax-based material (bi) is semicrystalline. The term "semicrystalline" characterizes polymers that have a high degree of intermolecular and intramolecular order. The semicrystalline nature of a polymer is determined by its primary transition temperature or crystalline melting temperature (T) as measured by differential scanning calorimetry (DSC). m This can be confirmed by [method / method].

[0065] Preferably, the first thermoplastic material and / or wax-based material (bi) is semi-crystalline because it exhibits a clear transition separating the fluid state from the solidified state. Furthermore, these materials are characterized by an increase in strength due to crystallization during solidification.

[0066] The first thermoplastic material and / or wax-based material (bi) and the second thermoplastic material and / or wax-based material (b-ii) can be selected from a variety of materials.

[0067] Suitable polymers include the following: Polyolefins; for example, Polyethylenes such as Lupolen 2420, Lupolen 5261 Z (available from LyondellBasell Industries Holdings BV), Sabic P6006NA (available from Sabic), BorPure® MB5569, BorPure® MB6561, BorPure® MB7541 (available from Borealis), Exceed® 1018, Enable® 2203MC (available from Exxon Mobile);

[0068] Polypropylenes such as BC250MO, BC545MO (available from Borealis), Adstif HA5029, Adstif HA600U, Adstif EA600P, Adstif EA648P, Clyrell RC213M, Clyrell RC5056, Hostalen PP H5416 (available from LyondellBasell Industries Holdings BV), Achieve® Advanced PP6936G2, Achieve® Advanced PP6945G1, Achieve® Advanced PP6035G1, ExxonMobil® PP1105E1, ExxonMobil® PP3155E5, ExxonMobil® PP9574E6 (available from Exxon Mobile);

[0069] Polyolefin copolymers of monomers such as ethene, propene, butene, and hexene, preferably propylene-ethylene copolymers such as Vistamaxx 8880 (available from Exxon Mobile);

[0070] Polyolefin copolymers with non-olefin monomers such as ethylene-n-butyl acrylate copolymers like EnBA EN 33091 (available from Exxon Mobile) or ethylene vinyl acetate copolymers like Escorene® UltraUL 8705 (available from Exxon Mobile) or ELVAX® 250 (available from Dow);

[0071] Modified polyolefins such as grafted polypropylene Licocene® PP MA 1332 (available from Clariant);

[0072] Poly(meth)acrylates such as polymethyl methacrylate (PMMA);

[0073] Polyamides such as polyamide 12; copolyamides, e.g., Griltex 2439 A, Griltex 1796 A, Griltex 1500 A, Griltex D 2638 A (available from EMS-CHEMIE HOLDING AG); Orgasol 3502 D (available from Arkema AG), UNI-REZ 2620, UNI-REZ 2638, UNI-REZ 2656, UNI-REZ 2674, UNI-REZ 2720, UNI-REZ 2291 (available from Kraton Corporation); polycarbonates, poly-α-methylstyrene, polyurethanes; water-soluble or water-dispersible thermoplastic polymers such as polyalkylene glycols, polyvinyl alcohol, polyvinyl lactam, polyvinylpyrrolidone, and copolymers thereof;

[0074] Polyesters, e.g., polycaprolactone, polylactide, polyglycolide, poly(hydroxyalkanoate), e.g., poly(3-hydroxybutyrate), poly(3-hydroxyvalerate), poly(hydroxybutyrate-co-hydroxyvalerate) ENMAT Y1000P (available from TianAn Biologic Materials Co.,Ltd.), phthalates, e.g., polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polycarbonate, copolyesters, e.g., Griltex 6E, Griltex 8E, Griltex 9E, Griltex D 1365E, Griltex D 1442E, Griltex D 1539E, Griltex D 1655E, Griltex D 1841E, Griltex D 1682E, Griltex D 1939E, Griltex D 2132E, Griltex D 2245E;

[0075] Polyethers such as polyether ether ketones or polyoxymethylenes; and mixtures thereof.

[0076] It is understood that it is also possible to combine polymers from different classifications.

[0077] Typically, polyamides can be produced by the reaction of a carboxylic acid and an amine to an amide, or by the reaction of a carboxylic acid and a partial / derivative of an amine. Polyamide homopolymers can be produced by the reaction of one monomer, such as polyamide 6 by ring-opening polymerization of ε-caprolactam, i.e., an amino acid or lactam having 4 to 25 carbon atoms. Polyamides can also be produced by the polycondensation reaction of a diamine having 4 to 25 carbon atoms and a dicarboxylic acid or salt thereof having 4 to 25 carbon atoms. For example, polyamide 6.6 is produced by the polycondensation reaction of hexamethylenediamine and adipic acid or hexamethylenediamine adipate. Copolyamides can be produced by the polycondensation reaction of various amines and various carboxylic acids, preferably a diamine having 4 to 25 carbon atoms such as hexamethylenediamine, preferably a dicarboxylic acid having 4 to 25 carbon atoms such as adipic acid, azelaic acid, dodecanedioic acid, preferably an aminocarboxylic acid having 4 to 25 carbon atoms such as aminoundecanoic acid, or salt thereof. By mixing various monomers and reacting them with ternary, quaternary, or polycomponent copolyamides, the properties of copolyamides, such as melting point and / or viscosity and / or adhesion, can be adjusted. For example, by mixing the monomers PA6 (ε-caprolactam), PA6.6 (hexamethylenediamine and adipic acid or hexamethylenediamine adipate), and PA12 (aminolauric acid) in a ternary system, a mixture of 20-40% PA6.6, 20-40% PA6, and 30-50% PA12 can have a melting point of 110-120°C. On the other hand, the melting points of pure PA6.6, PA6, and PA12 are 250°C, 215°C, and 176°C, respectively. Reactions with branched and / or aromatic carboxylic acids and / or branched and / or aromatic amines, as well as with further reaction partners such as ethers, esters, elastomers, and many others, are known in themselves.

[0078] Griltex 2439 A (available from EMS-CHEMIE HOLDING AG) is particularly preferred.

[0079] Polyolefins are a group of thermoplastic polymers formed by the polymerization of olefins such as propylene, ethylene, isoprene, and butene, which are commonly obtained from natural carbon sources such as crude oil and gas. Polyolefins contain only carbon and hydrogen atoms bonded together, with or without side branches. The properties of polyolefins depend primarily on the type of monomer and polymerization pathway, resulting in a wide range of molar masses and crystallinity. They can be easily modified by introducing various functional groups or mixed with other polymers and fillers to obtain properties suited to the required application. Polyolefins, such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), medium-density polyethylene (MDPE), metallocene polyethylene (mPE); cross-linked polyethylene (xPE); cyclic polyolefin (COC); syndiotactic, isotactic, and atactic polypropylene (sPP, iPP, aPP); random and homopolypropylene (rPP, hPP); thermoelastic polyolefin (TPO), as well as other special types of polyolefins, such as polybutene (PB), polymethylpentene (P4MP), (EP), ethylene vinyl acetate (EVA), and mixtures (blends) and copolymers thereof, can be used. Polyolefins are typically characterized by high chemical resistance (unaffected by alkalis and dilute acids) and low solvent solubility (unaffected by most solvents at temperatures below 60°C).

[0080] Vistamaxx 8880 and Achieve® Advanced PP6936G2 (available from Exxon Mobile) are particularly preferred.

[0081] Water-soluble or water-dispersible thermoplastic polymers, such as polyalkylene glycols or polyvinyl polymers selected from polyvinyl alcohol, polyvinyl lactams, and copolymers, contain functional groups that make the polymer soluble or dispersible in common solvents such as acetone, ethanol, and water. Among polyalkylene glycols, polyethylene glycol is preferred, for example, polyethylene glycol 200 to polyethylene glycol 20,000 (available from Carl Roth GmbH+ Co.KG). Polyvinyl alcohol can usually be produced by saponification of polyvinyl acetate. Properties of polyvinyl alcohol, such as its solubility in water, are affected by the degree of saponification. Among polyvinyl lactams, polyvinylpyrrolidone is particularly preferred. Copolymers of polyvinylpyrrolidone and polyvinyl alcohol can also be used.

[0082] Typically, polyesters are polymers obtained by the condensation reaction of difunctional reactants such as diols and diacids, and are characterized by the presence of ester functional groups (-COO-) along the chain. Linear polyesters can be classified into three classes: aliphatic polymers, partially aromatic polymers, and aromatic polymers. Aliphatic polyesters are obtained from aliphatic dicarboxylic acids (or esters) and aliphatic diols. Partially aromatic polyesters are obtained from aromatic dicarboxylic acids (or esters) and aliphatic diols. In aromatic polyesters, all ester functional groups are bonded to aromatic rings. Copolyesters can be obtained by using different difunctional reactants. Branched polyesters can be obtained by using reactants that are at least partially polyfunctional, i.e., beyond difunctionality.

[0083] Typically, polyethers are polymers that have ether bonds in the "backbone" of their polymer chains.

[0084] It is understood that the class of polymers described also includes derivatives of thermoplastic elastomers. Thermoplastic elastomers are multiblock copolymers composed of so-called crystallizable short hard segments and long flexible segments. Due to such chemical structures, thermoplastic elastomers exhibit a unique combination of thermoplastic and elastomer behavior, which can be beneficial. Thermoplastic elastomers based on polystyrene, polyolefins, polyvinyl, polyurethane, polyester, and polyamide are known on their own.

[0085] The term "wax" is a general technical term encompassing a group of organic substances that can generally be described in terms of their physical and technical properties. In particular, waxes are characterized by being solids with a melting point above 40°C (usually 50°C to 160°C) and low melt viscosity (less than 10 Pa·s at a temperature 10°C above the melting point). Waxes dissolve without decomposing. Waxes can also be classified into fossil-derived natural waxes such as paraffin and montan wax; naturally occurring natural waxes such as beeswax and carnauba wax; semi-synthetic waxes such as ethylene-bis-stearamide (also called chemically modified natural waxes); and synthetic waxes such as polyolefin waxes. In the context of this patent application, the expression "wax-based material" is intended to include not only waxes but also wax-based substances such as ester waxes, higher alcohols or polyhydric alcohols, higher fatty acids exhibiting wax-like properties, and mixtures thereof.

[0086] Suitable wax-based materials include the following: Paraffin waxes such as microcrystalline wax; Ester waxes such as beeswax, candelilla wax, and carnauba wax;

[0087] Esters of organic acids such as sulfonic acids or carboxylic acids, preferably esters of fatty acids having 6 to 40 carbon atoms, or esters of aromatic carboxylic acids such as benzoic acid, phthalic acid, or hydroxybenzoic acid;

[0088] Amide waxes, for example, amides of organic acids such as sulfonic acids or carboxylic acids, preferably amides of fatty acids having 6 to 40 carbon atoms, for example, oleic acid amides such as Deurex A27P (available from Deurex AG), erucic acid amides such as Deurex A26P (available from Deurex AG), ethylene-bis-stearic acid amides such as Deurex A20K (available from Deurex AG); sulfonamides such as N-ethyltoluene-4-sulfonamide;

[0089] Polyolefin waxes, e.g., polyethylene waxes, e.g., Deurex E06K, Deurex E08, Deurex E09K, Deurex E10K (available from Deurex AG), VISCOWAX® 111, VISCOWAX® 116, VISCOWAX® 123, VISCOWAX® 135 (available from Innospec Leuna); Polyethylene oxide waxes, e.g., Deurex EO40K, Deurex EO42, Deurex EO44P, Deurex E76K (available from Deurex AG), VISCOWAX® 252, VISCOWAX® 262, VISCOWAX® 271, VISCOWAX® 2628 (available from Innospec Leuna); Polyolefin copolymer wax, preferably ethylene vinyl acetate, e.g., VISCOWAX® 334, VISCOWAX® 453 (available from Innospec Leuna); Polypropylene waxes such as Deurex P36K, Deurex P37K (available from Deurex AG), Oxidized polypropylene wax;

[0090] Fischer-Tropsch waxes, for example, VESTOWAX EH100, VESTOWAX H2050 MG, VESTOWAX SH105, Shell GTL Sarawax SX105, Shell GTL Sarawax SX80 (available from Evonik Industries AG);

[0091] Higher organic acids, such as fatty acids, that have 10 to 40 carbon atoms; Higher alcohols or polyhydric alcohols, such as alcohols, having 10 to 40 carbon atoms; Polyethylene glycol; and mixtures thereof.

[0092] In one embodiment, the wax-based material is a mixture of various wax-based materials.

[0093] In one embodiment, binder component b-ii) is a plasticizable thermoplastic material and / or a wax-based material. "Plasticizable thermoplastic material and / or wax-based material" means a combination of a thermoplastic material and / or a wax-based material and a plasticizer. Generally, plasticizers are high-boiling-point liquids, usually with a boiling point above 180°C, and are miscible with thermoplastic materials and / or wax-based materials to reduce their melt viscosity. Those skilled in the art will understand that a ternary combination of a first thermoplastic material and / or wax-based material, a second thermoplastic material and / or wax-based material, and a plasticizer forms a homogeneous phase. Typically, plasticizers are polar compounds, meaning their chemical structure contains at least one highly electronegative heteroatom, such as an oxygen atom or a nitrogen atom.

[0094] Preferably, the plasticizable thermoplastic material and / or wax-based material b-ii) contains a plasticizer in an amount of up to 50 vol%, preferably up to 40 vol%, more preferably up to 30 vol%, most preferably up to 20 vol%, particularly up to 15 vol%, and particularly up to 10 vol%, relative to the total amount of b-ii).

[0095] Suitable plasticizers include the following: Liquid aliphatic carboxylic acid esters, such as dimethyl sebacate, di-n-octyl sebacate, dimethyl succinate, dimethyl adipate, dibutyl adipate, dioctyl adipate, dimethyl azelaate, dioctyl azelaate, di-n-butyl maleate, dioctyl maleate, butyl oleate, dimethyl hexanediate, benzyl laurate, methyl laurate, ethyl myristate, diacetyltriethyl citrate, acetyltributyl citrate; Liquid aromatic carboxylic acid esters, such as dimethyl phthalate, methyl 2-hydroxybenzoate, butyl 4-hydroxybenzoate, butyl benzoate, ethylhexyl benzoate, and bis(2-ethylhexyl) terephthalate; Phenylen alkylsulfonates; Liquid amides, for example, n-butylbenzenesulfonamide, N-ethyltoluene-2-sulfonamide, N-ethyl-4-toluenesulfonamide; Liquid organic acids, such as carboxylic acids including fatty acids like caprylic acid and myristoleic acid; Higher alcohols such as 1-decanol, 2-decanol, and 1-octadecanol; Polyhydric alcohols such as butanediol, ethylene glycol, and propylene glycol; and mixtures thereof.

[0096] Typically, paraffin waxes, such as microcrystalline wax, are derived from petroleum. For example, microcrystalline wax is obtained as a solid refined mixture mainly containing saturated aliphatic hydrocarbons, which are produced by the de-oiling of certain fractions resulting from the petroleum refining process.

[0097] Typically, ester waxes may be naturally occurring waxes or synthetically produced waxes. Preferably, naturally occurring ester waxes are selected from beeswax, candelilla wax, and carnauba wax. Preferably, synthetically produced ester waxes are selected from carboxylic acid esters, preferably fatty acid esters having 5 to 34 carbon atoms, more preferably fatty acid esters having 10 to 28 carbon atoms, or hydroxybenzoic acid esters. Preferably, ester waxes include hydroxybenzoic acid esters such as 4-hydroxybenzoic acid esters. Loxiol 2472 (behenyl 4-hydroxybenzoate ester, available from Emery Oleochemicals GmbH) is particularly preferred.

[0098] Typically, polyolefin waxes can be produced by thermally decomposing branched high molecular weight polyolefins or by directly polymerizing olefins. Suitable polyolefin waxes include, for example, homopolymers of propylene or higher 1-olefins, copolymers of propylene and ethylene or higher 1-olefins, or copolymers of each of them. The higher 1-olefins are preferably linear or branched olefins having 4 to 20, more preferably 4 to 6, carbon atoms. These olefins may have aromatic substituents conjugated to the olefinic double bond, such as 1-butene, 1-hexene, 1-octene or 1-octadecene, or styrene. Polyolefin waxes may be oxidized. Polyethylene waxes such as Deurex E06K (available from Deurex AG) are particularly preferred.

[0099] Typically, amide waxes such as sulfonic acids or carboxylic acids, preferably fatty acid amides, can be produced by a condensation reaction between an amide such as ethylenediamine and a sulfonic acid or carboxylic acid, preferably a fatty acid (having 5 to 34 carbon atoms, preferably 10 to 28 carbon atoms). Oleic acid amides such as Deurex A27P (available from Deurex AG), erucic acid amides such as Deurex A26P (available from Deurex AG), and ethylene-bis-stearic acid amides such as Deurex A20K (available from Deurex AG) are particularly preferred.

[0100] According to the present invention, the first thermoplastic material and / or wax-based material (bi) and the second thermoplastic material and / or wax-based material (b-ii) differ in at least one property selected from solubility in a solvent, decomposition induced by heat and / or reactants, and volatility. If the solubility of the binder components (bi) and (b-ii) differs and the first thermoplastic material and / or wax-based material (bi) is less soluble than the second thermoplastic material and / or wax-based material (b-ii), debinding is performed as a solvent debinding step using a suitable solvent. In other words, during solvent debinding, at least a portion of the second thermoplastic material and / or wax-based material (b-ii) dissolves in the suitable solvent, while the majority of the first thermoplastic material and / or wax-based material (bi) remains in the green part. Therefore, since the first thermoplastic material and / or wax-based material (bi) provides the necessary shape retention of the debinding portion, the first thermoplastic material and / or wax-based material (bi) is also hereafter referred to as the "skeleton polymer".

[0101] Preferably, the first thermoplastic material and / or wax-based material (bi) is a skeletal polymer selected from polyolefins, polyolefin waxes, polyamides, poly(meth)acrylates, polyesters, polyethers, and mixtures thereof. Suitable polyolefins include polyethylene, polypropylene, polyolefin copolymers with different monomers, polyolefin copolymers with non-olefin monomers (such as ethylene vinyl acetate or ethylene n-butyl acrylate copolymers), modified polyolefins, polyolefin waxes, and mixtures thereof. Representative examples of suitable polymers available on the market are those listed above.

[0102] In one embodiment, the backbone polymer has a DSC melting peak temperature T P : Having a temperature of less than 160°C, preferably less than 150°C, more preferably less than 140°C, most preferably less than 130°C, particularly less than 120°C, particularly less than 110°C, particularly less than 100°C, and particularly less than 90°C.

[0103] Preferably, the backbone polymer has a melt viscosity of less than 1500 Pa·s, preferably less than 1300 Pa·s, more preferably less than 1000 Pa·s, most preferably less than 800 Pa·s, particularly less than 600 Pa·s, particularly less than 500 Pa·s, particularly less than 400 Pa·s, particularly less than 300 Pa·s, particularly less than 200 Pa·s, and particularly less than 100 Pa·s, according to ISO 1133, using 2.16 kg at 160°C.

[0104] Preferably, the skeletal polymer has a melt viscosity of less than 1500 Pa·s, preferably less than 1300 Pa·s, more preferably less than 1000 Pa·s, most preferably less than 800 Pa·s, particularly less than 600 Pa·s, particularly less than 500 Pa·s, particularly less than 400 Pa·s, particularly less than 300 Pa·s, particularly less than 200 Pa·s, and particularly less than 100 Pa·s, using 2.16 kg at 190°C according to ISO 1133.

[0105] Preferably, the backbone polymer is melted according to ISO 1133, using 2.16 kg at 160°C, with a volumetric flow rate of at least 5 cm². 3 / 10 minutes, preferably at least 10 cm 3 / 10 minutes, more preferably at least 20 cm 3 / 10 minutes, most preferably at least 30 cm 3 / 10 minutes, especially at least 40cm 3 / 10 minutes, especially at least 50cm 3 / 10 minutes, especially at least 60cm 3 / 10 minutes, especially at least 70cm 3 / 10 minutes, especially at least 80cm 3 / 10 minutes, especially at least 90cm 3 / 10 minutes, especially at least 100cm 3 / 10 minutes, especially at least 110cm 3 / 10 minutes, especially at least 120cm 3 / 10 minutes, especially at least 130cm 3 / 10 minutes, especially at least 140cm 3 / 10 minutes, especially at least 150cm 3 / 10 minutes, especially at least 160cm 3 / 10 minutes, especially at least 170cm 3 / 10 minutes, especially at least 180cm 3 / 10 minutes, especially at least 190cm 3 / 10 minutes, especially at least 200cm 3 It takes 10 minutes.

[0106] Preferably, the skeletal polymer is melted according to ISO 1133, using 2.16 kg at 190°C, with a volumetric flow rate of at least 5 cm². 3 / 10 minutes, preferably at least 10 cm 3 / 10 minutes, more preferably at least 20 cm 3 / 10 minutes, most preferably at least 30 cm 3 / 10 minutes, especially at least 40cm 3 / 10 minutes, especially at least 50cm 3 / 10 minutes, especially at least 60cm 3 / 10 minutes, especially at least 70cm3 / 10 minutes, especially at least 80cm 3 / 10 minutes, especially at least 90cm 3 / 10 minutes, especially at least 100cm 3 / 10 minutes, especially at least 110cm 3 / 10 minutes, especially at least 120cm 3 / 10 minutes, especially at least 130cm 3 / 10 minutes, especially at least 140cm 3 / 10 minutes, especially at least 150cm 3 / 10 minutes, especially at least 160cm 3 / 10 minutes, especially at least 170cm 3 / 10 minutes, especially at least 180cm 3 / 10 minutes, especially at least 190cm 3 / 10 minutes, especially at least 200cm 3 It takes 10 minutes.

[0107] Preferably, b-ii) is selected from a polar wax or a plasticized thermoplastic material and / or wax-based material containing a polar plasticizer.

[0108] In this specification, the term “polar wax” means a wax whose chemical structure is essentially formed from or composed of carbon atoms and hydrogen atoms, and which contains at least one highly electronegative heteroatom such as an oxygen atom, a nitrogen atom, or a sulfur atom.

[0109] Preferably, the polar wax is selected from polyolefin waxes, ester waxes, amide waxes, higher organic acids, higher alcohols or polyhydric alcohols, polyethylene glycol, and mixtures thereof.

[0110] Preferably, ester waxes contain esters of organic acids. Preferably, amide waxes contain amides of organic acids such as sulfonic acids or carboxylic acids. The above are representative examples of suitable commercially available waxes.

[0111] Preferably, the polar wax has a dropping point in the range of 20 to 160°C, more preferably 30 to 150°C, even more preferably 35 to 140°C, particularly preferably 40 to 130°C, particularly preferably 40 to 120°C, particularly preferably 40 to 110°C, particularly preferably 40 to 100°C, and most preferably 40 to 90°C, according to DIN ISO 2176.

[0112] More preferably, the polar wax has a melt viscosity at 160°C according to DIN EN ISO 3104 of less than 30 Pa·s, preferably less than 20 Pa·s, more preferably less than 10 Pa·s, most preferably less than 5 Pa·s, especially less than 3 Pa·s, especially less than 1 Pa·s, especially less than 700 mPa·s, especially less than 300 Pa·s, especially less than 100 mPa·s, and especially less than 50 mPa·s.

[0113] More preferably, the polar wax has a melt viscosity at 120°C according to DIN EN ISO 3104 of less than 40 Pa·s, preferably less than 30 Pa·s, more preferably less than 20 Pa·s, most preferably less than 10 Pa·s, particularly less than 5 Pa·s, particularly less than 3 Pa·s, particularly less than 1 Pa·s, particularly less than 700 mPa·s, particularly less than 300 Pa·s, and particularly less than 100 mPa·s.

[0114] In a more preferred embodiment, b-ii) is a wax-based material selected from aromatic esters and aromatic sulfonamides, or a plasticized thermoplastic material and / or wax-based material comprising a plasticizer selected from aromatic esters and aromatic sulfonamides. The alcohol of the aromatic ester may be an alcohol having 1 to 40 carbon atoms. The aromatic sulfonamide may have at least one organic moiety having 1 to 40 carbon atoms in the amide nitrogen atom.

[0115] The following are particularly preferred combinations of bi) and b-ii) whose usefulness has been proven:

[0116] In one embodiment, (bi) is a polyamide, preferably a copolyamide. Also, (b-ii) is a wax-based material selected from esters and / or amides of organic acids, preferably aromatic esters and aromatic sulfonamides, or a plasticized thermoplastic material and / or wax-based material containing a plasticizer selected from aromatic esters and aromatic sulfonamides. The polyamide preferably has a DSC melting peak temperature T as defined above for the "backbone polymer". P It satisfies the restrictions regarding melt viscosity and melt volumetric flow rate.

[0117] In one embodiment, (bi) is a polyester, preferably polycaprolactone, or a copolyester, preferably poly(hydroxybutyrate-co-hydroxyvalerate), and / or a polyester-based thermoplastic elastomer. (b-ii) is an ester wax, an ester of an organic acid, an amide wax, a higher organic acid, and / or a higher alcohol or polyhydric alcohol. The polyester or copolyester preferably has a DSC melting peak temperature T as defined above for the "skeletal polymer". P It satisfies the restrictions regarding melt viscosity and melt volumetric flow rate.

[0118] In one embodiment, (bi) is a polyolefin such as polyethylene; polypropylene; polyolefin copolymers of monomers such as ethene, propene, butene, and hexane; polyolefin copolymers with non-olefin monomers such as ethylene n-butyl acrylate copolymer and / or ethylene vinyl acetate copolymer; and / or polyolefin wax; and / or modified polyolefin. Also, (b-ii) is an ester wax, an ester of an organic acid, an amide wax, a higher organic acid, and / or a higher alcohol or polyhydric alcohol. The polyolefin is preferably the DSC melting peak temperature T as defined above for the "skeleton polymer". P It satisfies the restrictions regarding melt viscosity and melt volumetric flow rate.

[0119] In one embodiment, the first thermoplastic material and / or wax-based material (bi) is polyethylene wax, and the second thermoplastic material and / or wax-based material (b-ii) is amide wax. The combination of polyethylene wax and amide wax is suitable for solvent debinding using ethanol or acetone as the solvent.

[0120] In preferred embodiments, the first thermoplastic material and / or wax-based material (bi) is a polyamide, and the second thermoplastic material and / or wax-based material (b-ii) is a wax, preferably an ester-based wax. The combination of polyamide and wax is suitable for solvent debinding using acetone as the solvent.

[0121] In preferred embodiments, the first thermoplastic material and / or wax-based material (bi) is polypropylene wax, and the second thermoplastic material and / or wax-based material (b-ii) is amide wax. The combination of polypropylene wax and amide wax is suitable for solvent debinding using ethanol as the solvent.

[0122] In preferred embodiments, the first thermoplastic material and / or wax-based material (bi) is polyethylene wax, and the second thermoplastic material and / or wax-based material (bii) is a water-soluble or water-dispersible thermoplastic polymer such as polyethylene glycol. The combination of polyethylene wax and a water-soluble or water-dispersible thermoplastic polymer is suitable for solvent debinders using water or an aqueous solution as a solvent.

[0123] The following table shows combinations of (bi), (b-ii), and solvents that have proven useful in carrying out the present invention. Many other combinations are possible and are not limited to this table.

[0124] [Table 1]

[0125] [Table 2]

[0126] [Table 3]

[0127] [Table 4]

[0128] The first thermoplastic material and / or wax-based material (bi) and the second thermoplastic material and / or wax-based material (b-ii) may each consist of a single material or a mixture of materials that satisfy the requirement of at least one property difference as defined above.

[0129] The binder component (b) may contain a dispersant. For example, one of the materials constituting the second thermoplastic material and / or the wax-based material (b-ii) may act as a dispersant. Otherwise, an external dispersant may be further added.

[0130] Typically, dispersants act as adhesion promoters and / or compatibilizers between binder components (bi) and / or (b-ii); and / or between non-organic particles (a) and binder component (b).

[0131] Preferably, the dispersant is selected from fatty acids having 10 to 24 carbon atoms, such as capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, or oleic acid, and is preferably stearic acid.

[0132] Preferably, the external dispersant is selected from metal salts of fatty acids. Typically, the metal can be selected from alkali metals, alkaline earth metals, or transition metals such as lithium, sodium, potassium, magnesium, calcium, strontium, barium, and zinc. Preferably, the fatty acid can be selected from fatty acids having 5 to 34 carbon atoms, preferably 10 to 28 carbon atoms, as described above. Preferred metal salts of fatty acids are selected from sodium stearate, magnesium stearate, zinc stearate, or magnesium oleate.

[0133] Because the viscosity of the binder component (b) is within the above range, in the molten state, the binder component (b) is uniformly and homogeneously dispersed among the sinterable non-organic particles (a) and bonded to the individual sinterable non-organic particles (a) or individual particulate raw material compounds.

[0134] To adjust the viscosity of the binder component (b), it may be desirable to incorporate a viscosity reducer or viscosity enhancer. The viscosity enhancer increases the viscosity of the binder component when melted. This increased viscosity prevents sagging of the sinterable non-organic particles, facilitates uniform particle flow, and provides resistance to segregation and sedimentation.

[0135] In particular, the viscosity of the binder component (b) is adjusted (i.e., decreased or increased) by a thickener or deviser. Devisers are used to lower the overall viscosity of the binder component. Thickeners are used to increase the overall viscosity of the binder component. Devisers can also act as plasticizers that enable control of the rheological properties and fluidity of the first thermoplastic material and / or wax-based material (bi), or the second thermoplastic material and / or wax-based material (b-ii).

[0136] Preferably, the thickener or deviser is selected from waxes and / or thermoplastic polymers, such as polyolefins and polyolefin waxes, polyamides and amide waxes, paraffin waxes, ester waxes; vinyl esters such as ethylene vinyl acetate; abietes; adipicates; alkyl sulfonates; amines and amides such as formamide, hydroxylalkylformamide, amines, and diamines; azelates; benzoates; citrates; chlorinated paraffins; ether-ester plasticizers; glutarates; hydrocarbon oils; isobutyrates; maleates; oleates; phosphates; phthalates; sulfonamides; oily liquids such as peanut oil, fish oil, and castor oil; and mixtures thereof. Preferably, polyethylene wax Deurex E09K having a viscosity of <40 mPa·s at 140°C can be used as a deviser, and Deurex E25 having a viscosity of 4000 mPa·s at 140°C or even higher molecular weight polyolefin compounds can be used as thickeners.

[0137] In one embodiment, a thickener or dethickener and / or dispersant may be present in an amount of 0 to 15 vol%, preferably 0.01 to 10 vol%, more preferably 0.02 to 8 vol%, and most preferably 0.5 to 6 vol%, based on the total volume of binder component (b).

[0138] In one embodiment, binder component (b) is a temperature of 130°C; and 1 s -1 The viscosity measured at the shear rate is less than 6 Pa·s, preferably less than 5 Pa·s, more preferably less than 4 Pa·s, most preferably less than 3 Pa·s, especially less than 2 Pa·s, especially less than 1 Pa·s, especially less than 700 mPa·s, especially less than 400 mPa·s, and especially less than 200 mPa·s. The viscosity is measured in accordance with EN ISO 3219:1994.

[0139] In one embodiment, binder component (b) is a temperature of 110°C; and 1 s -1Viscosity measured at a shear rate is less than 10 Pa·s, preferably less than 8 Pa·s, preferably less than 6 Pa·s, more preferably less than 5 Pa·s, most preferably less than 4 Pa·s, especially less than 3 Pa·s, especially less than 2 Pa·s, especially less than 1 Pa·s, especially less than 600 mPa·s, and especially less than 300 mPa·s. Viscosity measurements are performed in accordance with EN ISO 3219:1994.

[0140] In one embodiment, binder component (b) is a temperature of 100°C; and 1 s -1 Viscosity measured at a shear rate of less than 10 Pa·s, preferably less than 8 Pa·s, more preferably less than 6 Pa·s, most preferably less than 5 Pa·s, especially less than 4 Pa·s, especially less than 3 Pa·s, especially less than 2 Pa·s, especially less than 1 Pa·s, and especially less than 500 mPa·s. Viscosity measurements are performed in accordance with EN ISO 3219:1994.

[0141] Particulate raw material compound

[0142] In this specification, the term “particulate” means that the raw material compound is composed of particles of any shape, such as amorphous, cylindrical, ellipsoidal, or nearly spherical, or fine fibers.

[0143] The particulate raw material compound of the present invention comprises sinterable non-organic particles (a) and a binder component (b) as described above, and is useful in molding and sintering methods.

[0144] Therefore, the present invention further relates to particulate raw material compounds for use in molding and sintering methods, and includes the following: a) Sinterable non-organic particles dispersed throughout the particulate raw material compound (at least 80% of the particles have a maximum particle size in the range of 100 nm to 400 μm A max (Having a particle size distribution that includes) and b) The binder components mentioned above.

[0145] Sinterable non-organic particles (a) include conventionally known sinterable materials. Typically, sinterable non-organic particles (a) are selected from metals, alloys, glass particles, and ceramic particles.

[0146] In one embodiment, the metal is selected from iron, stainless steel, steel, copper, bronze, aluminum, tungsten, molybdenum, silver, gold, platinum, titanium, nickel, cobalt, chromium, zinc, niobium, tantalum, yttrium, silicon, magnesium, calcium, and combinations thereof. Preferably, at least 85%, preferably at least 90%, more preferably at least 95%, and most preferably at least 99% of the metal particles have a maximum particle size A in the range of 500 nm to 400 μm, preferably 1 μm to 150 μm, more preferably 3 μm to 50 μm, and most preferably 5 μm to 25 μm. max It has a particle size distribution.

[0147] Preferably, the alloy is selected from stainless steel (316L, 17-4 PH), steels such as chromium-nickel steel, copper alloys such as bronze and Hovadur, nickel-based alloys such as Hastelloy or Inconel, cobalt-chromium alloys such as cobalt and Stellite, aluminum alloys such as aluminum 6061, tungsten alloys, and titanium alloys such as grades 1 to 5 (Ti-6Al-4V) through grade 38 according to ASTM.

[0148] In one embodiment, the ceramic particles are selected from oxides such as aluminum oxide, silicon oxide, zirconium oxide, titanium oxide, magnesium oxide, and yttrium oxide; carbides such as silicon carbide and tungsten carbide; nitrides such as boron nitride, silicon nitride, and aluminum nitride; silicates such as steatite, cordierite, and mullite; and combinations thereof. Preferably, at least 85%, preferably at least 90%, more preferably at least 95%, and most preferably at least 99% of the ceramic particles have a maximum particle size A in the range of 200 nm to 25 μm, preferably 300 nm to 10 μm, more preferably 400 nm to 7 μm, and most preferably 500 nm to 3 μm.max It has a particle size distribution having

[0149] In one embodiment, the glass particles are selected from non-oxide glasses such as halide glasses and chalcogenide glasses; oxide glasses such as phosphate glasses, borate glasses, silicate glasses, for example, aluminosilicate glasses, lead silicate glasses, borosilicate glasses, sodium lime silicate glasses, quartz glasses, alkali silicate glasses; and combinations thereof. Preferably, at least 85%, preferably at least 90%, more preferably at least 95%, most preferably at least 99% of the glass particles have a maximum particle size A in the range of 200 nm to 25 μm, preferably 300 nm to 10 μm, more preferably 400 nm to 7 μm, most preferably 500 nm to 3 μm max It has a particle size distribution having

[0150] Preferably, the sinterable inorganic particles (a) can include a combination of more than one of the above-mentioned metals, alloys, glass particles and ceramic particles, for example, a hard metal or a metal matrix composite material (also called a metal-ceramic composite material).

[0151] In one embodiment, the particulate raw material compound contains the sinterable inorganic particles (a) in an amount of about 0.70 to 0.99·φ r Preferably, about 0.75 to 0.98·φ r More preferably, about 0.80 to 0.96·φ r Most preferably, about 0.82 to 0.95·φ r Especially about 0.84 to 0.94·φ r Especially about 0.86 to 0.93·φ r in an amount of. φ r is the critical solid content filling amount on a volume basis. The remainder is composed of the binder component b).

[0152] Typically, the term "critical solids loading" refers to the volume amount of sinterable inorganic particles in the feed compound at the critical limit. The said "critical limit" is reached when adding sinterable inorganic particles to the feed compound causes the relative viscosity to become infinite, making the feed compound hard and non-flowing. Physically, the "critical solids loading" defines the maximum packing composition of particles while retaining a continuous material. And it is the limit beyond which it becomes impossible to continue filling the binder matrix with solid powder. In this context, the term "relative viscosity" indicates the viscosity of the feed compound relative to that of the pure binder, separating the influence of sinterable inorganic particles. The viscosity of the feed compound increases with the addition of sinterable inorganic particles.

[0153] There are several methods to determine the critical solids loading. For example, by continuously adding metal powder to the binder, the peak torque of the kneader can be determined. Usually, after reaching the critical solids loading, as the feed compound becomes brittle, the torque decreases again. Alternatively, pycnometer measurements can also be used: up to the critical solids loading, the theoretical density coincides with the measured density in the pycnometer, but beyond the critical solids loading, the measured density is lower than the theoretical density due to pores (see also R.M. German, Powder Injection Molding, Metal Powder Industries Federation 1990, p. 129 - 130). Using rheology measurements, the value of the critical solids loading can also be estimated by plotting φ·η r :(η r - 1) against φ (J.S. Chong, E.B. Christiansen, A.D. Baer, J. Appl. Polym. Sci. 1971, 15, 2007 - 2021). In this context, φ represents the loading and η r represents the relative viscosity.

[0154] Alternatively, in one embodiment, the particulate raw material compound contains sinterable non-organic particles (a) in an amount of about 20-90 volume%, preferably 30-80 volume%, more preferably 40-75 volume%, most preferably 45-70 volume%, and particularly 50-65 volume%. It also contains a binder component (b) in an amount of about 10-80 volume%, preferably 20-70 volume%, more preferably 25-60 volume%, most preferably 30-55 volume%, and particularly 35-50 volume%.

[0155] Binder component (b) comprises at least two binder components: a first thermoplastic material and / or a wax-based material (bi), and a second thermoplastic material and / or a wax-based material (b-ii). Optionally, binder component (b) may contain further functional additives from the viewpoint of good processability.

[0156] Each particulate raw material compound contains multiple sinterable non-organic particles (a) dispersed throughout the compound within a matrix of binder component (b), and held together by the binder component (b). The presence of multiple sinterable non-organic particles (a) per particulate raw material compound makes it possible to make the shape of the particulate raw material compound independent of the shape of the sinterable non-organic particles (a). Therefore, for example, a particulate raw material compound with approximately spherical particles can be manufactured without the sinterable non-organic particles (a) having to be spherical. This reduces manufacturing costs because sinterable non-organic particles (a) with any or irregular particle shapes or a wider particle size distribution are more readily available than powders with a specific, for example, spherical particle shape.

[0157] In one embodiment, the particulate raw material compound is prepared at a temperature of 130°C and a shear rate of 1 s. -1 The measured viscosity is less than 600 Pa·s, preferably less than 400 Pa·s, more preferably less than 350 Pa·s, most preferably less than 250 Pa·s, particularly less than 150 Pa·s, particularly less than 50 Pa·s, and particularly less than 10 Pa·s. The viscosity is measured in accordance with EN ISO 3219:1994.

[0158] In one embodiment, the particulate raw material compound is prepared at a temperature of 110°C and a shear rate of 1 s. -1 The viscosity measured is less than 800 Pa·s, preferably less than 550 Pa·s, more preferably less than 450 Pa·s, most preferably less than 350 Pa·s, particularly less than 200 Pa·s, particularly less than 100 Pa·s, and particularly less than 60 Pa·s. The viscosity is measured in accordance with EN ISO 3219:1994.

[0159] In one embodiment, the particulate raw material compound is prepared at a temperature of 100°C and a shear rate of 1 s. -1 The viscosity measured is less than 1000 Pa·s, preferably less than 850 Pa·s, more preferably less than 700 Pa·s, most preferably less than 550 Pa·s, particularly less than 400 Pa·s, particularly less than 250 Pa·s, and particularly less than 100 Pa·s. The viscosity is measured in accordance with EN ISO 3219:1994.

[0160] The particulate raw material compound is produced, for example, by spray-drying a suspension of sinterable non-organic particles (a) and a solvent (e.g., an alcohol solvent in which a binder component (b) is dissolved). Alternatively, a solidified molten product of a binder component (b) in which sinterable non-organic particles (a) are dispersed may be pulverized. Furthermore, a larger particulate raw material compound may be compounded in an extruder and then granulated.

[0161] Typically, when used for 3D printing and press processing, the particulate raw material compound consists of at least 80% by volume, preferably at least 90% by volume, more preferably at least 95% by volume, and most preferably at least 99% by volume, with a maximum particle size B in the range of 0.005 to 0.3 mm, preferably 0.008 to 0.2 mm, more preferably 0.01 to 0.2 mm, and most preferably 0.015 to 0.15 mm. max It has a particle size distribution.

[0162] When used in an injection molding process, the particulate raw material compound has a maximum particle size B in the range of 1 to 10 mm, preferably 2 to 8 mm, and more preferably 3 to 5 mm. max It holds.

[0163] method

[0164] Furthermore, the present invention relates to a method comprising the following steps: - A process of fusing multiple particulate raw material compounds to obtain green parts; and - A step of partially debinding a green part by selectively removing a second thermoplastic material and / or a wax-based material (b-ii) in order to obtain a brown part comprising sinterable non-organic powder particles (a) bonded together by a first thermoplastic material and / or a wax-based material (bi).

[0165] In one embodiment, the method is selected from additive manufacturing methods such as laser additive manufacturing or extrusion additive manufacturing; injection molding methods such as medium-pressure injection molding or low-pressure injection molding; press working methods; and casting methods, preferably selected from additive manufacturing methods such as laser additive manufacturing or extrusion additive manufacturing.

[0166] In the context of this patent application, the term “fuse” means “selectively melting and solidifying” when the method is selected from additive manufacturing using radiation; or the term “fuse” means “melting and solidifying” when the method is selected from injection molding, casting, microfiber printing, or pellet printing; or the term “fuse” means “compressing” or “compressing and partially or completely melting and solidifying” when the method is selected from press working.

[0167] By carefully selecting the components and process parameters, crack-free parts can be suitably obtained. Such cracks occur, for example, when the debindering process is carried out too quickly or under harsh conditions. Therefore, the components and process parameters are preferably selected to avoid harmful conditions.

[0168] Typically, in additive manufacturing methods that use radiation from laser arrays, radiation heating elements, etc., such as laser additive manufacturing or HP's MultiJet Fusion, particulate material compounds are applied in layers, then densified and solidified, for example, by cooling. During densification, the binder component (b) contained in the particulate material compound is selectively melted in layers, for example, by electromagnetic radiation from a laser.

[0169] In a preferred embodiment, the step of fusing multiple particulate material compounds includes the following steps: - A step of providing the first layer of raw material compound particles; - A process of selectively densifying the first layer of raw compound particles and bonding the compound particles together in a predetermined manner to produce a first molded part layer; - A step of providing an additional layer of at least one raw material compound particle on the first molded part layer; and - A step of selectively densifying an additional layer of raw compound particles and bonding the raw compound particles together in a predetermined manner to generate at least one additional molded part layer, wherein the first molded part layer and the additional molded part layer form a green part.

[0170] Typically, extrusion additive manufacturing is a method of creating green parts by supplying raw material compounds as fine fibers or granules, melting them in a heated printer extruder head, and depositing them in layers. The print head is computer-controlled to determine the print shape. Usually, the head moves two-dimensionally, depositing one horizontal plane or layer at a time. Then, the workpiece or print head is moved slightly vertically to start a new layer. After the printing process, the molded raw material compound can be removed as a solidified green part. The green part contains sinterable non-organic powder particles and a binder.

[0171] Typically, injection molding methods such as medium-pressure injection molding or low-pressure injection molding involve mixing finely powdered raw materials with a binder to create a raw material compound, which is then melted and injected (molded) into a mold in a liquid state. After cooling, the molded raw material compound solidifies within the mold and can be removed, yielding a green part (molded product). The green part contains the raw materials and binder. When the fine powder material is a metal or alloy, this method is called metal injection molding (MIM). When the fine powder material is a ceramic, the method is called ceramic injection molding (CIM). Generally, methods involving fine powder material are called powder injection molding (PIM). Further suitable sinterable non-organic powder particles include, for example, glass, ceramics, polymers, or mixtures thereof.

[0172] Generally, the casting process involves melting a raw material compound and pouring it into a mold in a liquid state (forming it). After cooling, the formed raw material compound solidifies within the mold and is removed to obtain a green part. The green part contains the raw material and binder. In one embodiment, the mold is a lost casting mold. That is, the mold can only be used for one green part, as it must be destroyed, for example, to obtain the green part. Lost casting molds can be manufactured by various methods such as casting or additive manufacturing, for example, extrusion additive manufacturing or inkjet additive manufacturing. The lost form can be printed with a polymer soluble in a solvent, for example, acrylonitrile-butadiene-styrene (ABS) in acetone. In one embodiment, a portion of the mold is printed, and that portion is at least partially filled with the raw material compound. These steps are repeated until the printing and filling of the mold are complete. Preferably, both the mold and the green part can be dissolved in the same solvent and debindered. Green parts consist of sinterable non-organic powder particles and a binder. After the casting process, the green parts undergo a conditioning operation to densify (sinter) the powder.

[0173] Typically, in the press working method, green parts can be formed from a particulate raw material compound containing finely powdered raw materials and a binder by applying high pressure to multiple particulate raw material compounds to densify them (form by press working). Preferably, densification may involve heat, and the particulate raw material compound may be partially or completely melted. The green parts contain sinterable non-organic powder particles and a binder. After the press working molding process, the green parts undergo a conditioning operation to densify (sinter) the powder.

[0174] The aforementioned processes can also be combined. Preferred combinations of processes are described in detail below. These processes can be carried out using particulate raw material compounds as described above. Alternatively, any other particulate raw material compound containing an organic binder component and sinterable non-organic particles can be used. In particular, the binder component can be a first thermoplastic material and / or a wax-based material and a second thermoplastic material and / or a wax-based material, wherein the first thermoplastic material and / or a wax-based material and the second thermoplastic material and / or a wax-based material differ in at least one property as described above.

[0175] In one embodiment, the green parts are cast or molded, and then printed on the green parts through an extrusion-based process.

[0176] In one embodiment, green parts are manufactured through various processes (for example, some parts are 3D printed and others are molded), and then extracted and joined as green or brown parts. Suitable joining methods are selected from welding and bonding methods. Suitable adhesives for bonding are selected from a slurry containing a polymeric binder such as polyvinyl alcohol, galantine, or agar, a solvent such as water or alcohol, and suitable non-organic particles, preferably sinterable non-organic particles, more preferably sinterable non-organic particles with the same composition as the sinterable non-organic particles of the green or brown parts.

[0177] In one embodiment, the method includes the following steps: 1. The process of providing the first green part by additive manufacturing; - The process of placing the first green part into the mold; - A step of melting a portion of the particulate raw material compound according to the present invention, casting or injection molding the molten portion in a mold, and having the molten portion form the interface of the first green part; - A process to solidify the first green part so that it becomes a single unit with the cast green part; - A process of partially debinding cast green parts to obtain brown parts.

[0178] Preferably, the first green part is manufactured by a 3D printing method in which the first green part shrinks uniformly and does not distort during the sintering process. Therefore, preferably, the first green part is manufactured by selectively melting and solidifying a plurality of particulate raw material compounds according to the present invention by additive manufacturing to obtain the first green part.

[0179] In other words, the first green part is manufactured by 3D printing, and the 3D printed first green part is then placed in a mold and overmolded and / or overcast.

[0180] Such a combination of processes is advantageous in terms of process efficiency when only one or more major parts of the manufactured component have a complex design and / or require high geometric precision, while the remaining parts of the component (e.g., around the major parts) require relatively low geometric precision. It also allows for various material combinations, such as in two-component metal injection molding. In other words, a first green part is manufactured from one material, and then the 3D printed first green part is placed in a mold and overmolded and / or overcast with another suitable material.

[0181] In this case, the first green part is manufactured from the first portion of the raw compound by 3D printing and placed in a mold. Then, the second portion of the raw compound is melted and cast or injected into the mold.

[0182] The raw material compound of the present invention is particularly suitable for carrying out such a combination of processes. This is due to the high dimensional stability of the first green part and the high compatibility of the molten second part of the raw material compound, i.e., the high ability of the molten second part to adhere to the first green part.

[0183] The mold is configured to receive the molten second portion of the raw compound such that it forms an interface with the first green part. In other words, the molten second portion comes into contact with the first green part for bonding and becomes a single unit of the cast green part after solidification. For example, the molten second portion is deposited adjacent to the first green part, or deposited adjacent to and on top of the first green part.

[0184] Preferably, the mold and / or first green part are heated to at least 40°C, preferably at least 50°C, more preferably at least 60°C, and most preferably at a DSC melting peak temperature T P The machine is preheated to a temperature close to [a certain temperature]. This is to promote better bonding between the first green part and the second cast part of the raw material compound.

[0185] In one embodiment, the method includes the following steps: - Process of providing the first green part; - The process of placing the first green part into the build chamber; - A step of providing a first layer of raw material compound particles on the first green part; - A process of selectively densifying the first layer of raw compound particles and bonding the compound particles to each other in a predetermined manner to produce a first molded part layer bonded to the first green part; - Optionally, a step of providing an additional layer of at least one raw material compound particle on the first molded part layer; and - A step of selectively densifying an additional layer of raw material compound particles, bonding the raw material compound particles to each other in a predetermined manner to create at least one additional molded part layer bonded to the first molded part layer, and integrating the first molded part layer and the additional molded part layer with the first green part to form a single integrated part; - A process of partially removing the binder from a single piece to obtain brown parts.

[0186] In this case, the first green part is manufactured from the first part of the raw material compound by molding, casting, and additive manufacturing processes and placed in the build chamber. Subsequently, the second part of the raw material compound is applied, and a portion of the particulate raw material compound is melted using radiation from a laser array, radiation heating element, etc. For example, in laser additive manufacturing or HP's multi-jet fusion method, the particulate raw material compound is applied in layers, then densified and solidified, for example, by cooling. During densification, the binder component (b) contained in the particulate raw material compound is selectively melted in layers, for example, by electromagnetic radiation from a laser.

[0187] Such a combination of processes is advantageous in terms of process efficiency when only one or more major parts of the manufactured component have a complex design and / or require high geometric precision, while the remaining parts of the component (e.g., around the major parts) require relatively low geometric precision. It also allows for various material combinations, such as in two-component metal injection molding. In other words, the first green part is manufactured from one material, and the applied particulate raw material compound is another suitable material.

[0188] The raw material mixture of the present invention is particularly suitable for carrying out such combination processes. This is due to the high dimensional stability of the first green part and the high compatibility of the molten second part of the raw material compound, i.e., the high ability of the molten second part to adhere to the first green part.

[0189] The build chamber is configured to receive particulate raw material compound so as to cover the first green part. When selectively densified, for example by laser additive manufacturing, the raw material compound particles bond to each other in a predetermined manner, producing a first molded part layer bonded to the first green part via a common interface. Next, at least one additional layer of raw material compound particles is selectively densified on the first molded part layer, causing the raw material compound particles to bond to each other in a predetermined manner, producing at least one additional molded part layer bonded to the first molded part layer. The first molded part layer and the additional molded part layers together with the first green part form a single integrated part. The integrated part can then be removed from the build chamber and any unbonded particulate raw material compound can be removed.

[0190] Preferably, the first green part is melted at a temperature of at least 40°C, preferably at least 50°C, more preferably at least 60°C, and most preferably at least the DSC melting peak temperature T P It is preheated to a temperature close to [a certain temperature]. This is to promote better bonding between the first green part and the second part of the raw material compound.

[0191] In each step, the binder component (b) is dispersed between sinterable non-organic particles (a) and holds them together after solidification. After the green parts are manufactured, they are removed from the unmolten layer or mold.

[0192] According to one embodiment, the partial removal of a temporary organic binder can be achieved by one or more of the following steps: - A process in which the first thermoplastic material and / or wax-based material (bi) has lower solvent solubility than the second thermoplastic material and / or wax-based material (b-ii), and partial debindering is carried out by solvent treatment in a solvent treatment step; - A process in which the first thermoplastic material and / or wax-based material (bi) has different thermal decomposition properties and / or different reactant decomposition properties from the second thermoplastic material and / or wax-based material (b-ii), and partial binder removal is performed by heat treatment in a heat treatment step and / or chemical treatment in a chemical treatment step; - A process in which a first thermoplastic material and / or wax-based material (bi) has a different vapor pressure from a second thermoplastic material and / or wax-based material (b-ii) at a specific temperature, and partial debindering is performed by heat treatment in a heat treatment step.

[0193] Among the steps for partially removing the binder, a solvent treatment step is preferred.

[0194] By using a first thermoplastic material and / or wax-based material (bi) having different solvent solubility and / or different thermal decomposition properties and / or different reactant decomposition properties and / or different volatility compared to a second thermoplastic material and / or wax-based material (b-ii), one or more binder components can be selectively removed during the debindering process. Preferably, the second thermoplastic material and / or wax-based material (b-ii) is selectively removed, while the first thermoplastic material and / or wax-based material (bi) is not removed. The parts obtained after the debindering process are called brown parts. The brown parts consist of sinterable non-organic particles (a) bonded together by the first thermoplastic material and / or wax-based material (bi) and optionally remaining second thermoplastic material and / or wax-based material (b-ii).

[0195] The remaining binder components held in the brown parts provide stable brown parts with sufficient strength for handling and transport between the debinding and sintering processes.

[0196] In the solvent treatment step, the green parts are immersed in a suitable solvent. Preferably, the solvent is selected such that the first thermoplastic material and / or wax-based material (bi) is less soluble in the solvent than the second thermoplastic material and / or wax-based material (b-ii), or, more preferably, the first thermoplastic material and / or wax-based material (bi) is intrinsically insoluble in the solvent and the second thermoplastic material and / or wax-based material (b-ii) is soluble in the solvent. Suitable solvents are selected from alcohols such as ethanol or propanol; aromatic compounds such as benzene, toluene, or xylene; esters such as ethyl acetate; ethers such as diethyl ether or tetrahydrofuran; ketones such as acetone; alkanes such as hexane or heptane; halogenated hydrocarbons such as n-propyl bromide, trichloroethylene, perchloroethylene, and n-methylpyrrolidine; water; supercritical gases; and mixtures thereof. During the solvent treatment step, the solvent is preferably kept at a temperature in the range of 20-100°C, preferably 25-80°C, and more preferably 30-60°C. L It is maintained in that state.

[0197] In the chemical treatment step, the green parts to be debindered are treated in a reactive gas atmosphere. Preferably, the green parts are placed in a reactive gas atmosphere so that the reactive gas penetrates into the pores of the green parts containing the binder component. The binder component (b-ii) is degraded / decomposed by reaction with the reactive gas, and after the removal of the binder component (b-ii), debindered green parts (brown parts) are obtained. Such a reactive gas atmosphere may contain gas, preferably nitric acid. Preferably, the chemical treatment step is carried out at a high temperature level. For example, the temperature in the chemical treatment step can be in the range of 40 to 150°C, preferably 60 to 140°C, and more preferably 80 to 130°C.

[0198] Partial removal of the binder components (b-ii) yields the porous structure of the brown parts. Sinterable non-organic particles (a) are held together by the first thermoplastic material and / or wax-based material (bi).

[0199] Sintering process

[0200] In one embodiment, the method further includes the step of sintering brown parts to obtain sintered parts.

[0201] For this purpose, the brown parts are preferably subjected to a sintering process after a debindering process. During the sintering process, the first thermoplastic material and / or wax-based material (bi) is removed, and the debindered parts (brown parts) are sintered to obtain sintered parts. Typically, further removal of the binder and sintering of the brown parts results in shrinkage.

[0202] Preferably, residual binders are removed at a first temperature T1 in the range of 100-750°C, preferably 150-700°C, more preferably 200-650°C, and most preferably 300-600°C. The appropriate temperature T1 may also depend on the atmosphere. Preferably, the first temperature T1 is selected as a function of the residual binder components, e.g., a first thermoplastic material and / or wax-based material (bi). The removal of the first thermoplastic material and / or wax-based material (bi) at temperature T1 is performed over a time Δt1 that depends on the part geometry and is particularly proportional to the square of the thickness of the part being manufactured. Preferably, the time Δt1 is selected so that at least 95%, preferably at least 99%, more preferably at least 99.9%, and most preferably 100% of the binder components (bi) and (b-ii) are removed. The binder that is not removed cannot be used as a polymer binder within the part, but diffuses into the metal part as, for example, carbon, increasing the carbon content in the metal part. Thermal debindering may be carried out at multiple temperatures T1, for example, temperature T 1a The removal of a portion of the first thermoplastic material and / or wax-based material (bi) in time Δt 1aIt was carried out during the period, at temperature T 1b The removal of the remaining first thermoplastic material and / or wax-based material (bi) in time Δt 1b It will be implemented during this period.

[0203] The sinterable non-organic particles (a) partially form a sintered neck, so the parts are held together even after the remaining binder components are removed. The microporous structure of the parts allows for rapid and uniform thermal binder removal.

[0204] Undesirable chemical reactions during thermal binder removal can be avoided by an inert gas atmosphere, a reducing atmosphere, or a high vacuum. An inert gas atmosphere, in particular, may contain at least one noble gas, which can be preferably selected from, for example, nitrogen, helium, and argon. A reducing atmosphere may include gases such as hydrogen, carbon dioxide, and / or carbon monoxide.

[0205] Preferably, sintering is carried out at a second temperature T2 in the range of 600 to 2000°C, preferably 800 to 1800°C, and more preferably 900 to 1500°C. In the manufacture of ceramic and / or glass parts, the second temperature T2 is preferably in the range of 600 to 2400°C, more preferably 800 to 2200°C, and most preferably 1100 to 2000°C. In any case, the sintering temperature T2 is lower than the melting temperature of the sinterable non-organic particles. Sintering at the second temperature T2 is carried out for a time Δt2, which depends on the shape of the part and the material being sintered. Preferably, the time Δt2 is long enough so that further sintering does not cause a significant change in the porosity of the part. Sintering can be carried out at multiple temperatures T2. For example, temperature T 2a Then, the sintering process takes time Δt 2a This will be carried out during the following period, at temperature T 2b Then, another sintering process is performed over time Δt 2b It will be implemented during this period.

[0206] During this sintering process, the molded part shrinks without essentially affecting its shape. The powder particles fuse together, and the voids between the powder particles disappear. Therefore, the density of the product increases and the product shrinks during sintering. Typically, depending on the material of the product and its subsequent application, the sintering process is completed when the product reaches a density of approximately 90-100% of the volume of solids that make up the powder.

[0207] Preferably, after the sintering process, the component is completely free of binder. As a result, the component forms a dense, integrated structure.

[0208] The present invention will be described in detail below with reference to the attached drawings and examples. [Brief explanation of the drawing]

[0209] [Figure 1] Figure 1 shows the second heating gradient of the DSC measurement of binder component 1-B to determine the melting peak temperature TP of 1-B. [Figure 2] Figure 2 shows the second heating gradient of the DSC measurement of binder component 3-B to determine the melting peak temperature TP of 3-B. [Figure 3] Figure 3 shows the second heating gradient of the DSC measurement of binder component 4-B to determine the melting peak temperature TP of 4-B. [Figure 4] Figure 4 shows the storage modulus G' curve and loss modulus G'' curve of dynamic viscoelastic measurements during heating of binder component 1-B to determine the crossover temperature Tcross of 1-B. [Figure 5] Figure 5 shows the storage modulus G' curve and loss modulus G'' curve of dynamic viscoelastic measurements during heating of binder component 3-B to determine the crossover temperature Tcross of 3-B. [Figure 6] Figure 6 shows the storage modulus G' and loss modulus G'' curves of the dynamic viscoelastic measurement of binder component 4-B to determine the crossover temperature Tcross of 4-B. Figure 6 was recorded during cooling because a high value of Tcross was recorded during cooling. [Figure 7] Figure 7 shows cylindrical test specimens (green parts) 1-F (Figure 7A), 2-F (Figure 7B), 3-F (Figure 7C), and 4-F (Figure 7D) obtained from the raw material compound according to Table 2. [Figure 8] Figure 8 shows the front and back views of test specimens (green parts) obtained by the molding process using raw material compounds 1-F (Figure 8A), 2-F (Figure 8B), 3-F (Figure 8C), and 5-F (Figure 8D). [Figure 9] Figure 9 shows the side and top views of the notched test specimens obtained from the raw material compound according to Table 2, 1-F. [Figure 10] Figure 10 shows the side and top views of the notched test specimens obtained from the raw material compound according to Table 2, section 2-F. [Figure 11] Figure 11 shows the side and top views of the notched test specimens obtained from the raw material compound according to Table 2, 3-F. [Figure 12] Figure 12 shows a rectangular first green part 3D printed in a silicone mold (Figure 12A) and a one-piece part manufactured by overcasting the rectangular first green part with a molten raw material compound (Figure 12B). [Examples]

[0210] Examples method Dynamic viscoelasticity measurement Determination of storage modulus and loss modulus

[0211] Dynamic viscoelastic measurements to determine the storage modulus and loss modulus were performed using a NETZSCH Kinexus Pro+ instrument equipped with a Peltier temperature control measurement system, in accordance with DIN 53019-4:2016-10. The measurements were performed using a plate-to-plate geometry with a diameter of 40 mm and a vibration mode of 1 Hz. The measurement gap was 0.15 mm. To perform the measurements, the geometry was heated to 110°C (160°C in Example 2-B of Table 3a, and 140°C in Example 3-B of Table 3a), and the sample was placed on the lower plate at the higher temperature. First, it was cooled from 110°C (140°C, 160°C) to 60°C, and then heated to 110°C (140°C, 160°C). The cooling and heating rates were 1 K / min, respectively. In the cooling gradient, the measurement was started in a deformation control mode with a constant deformation γ = 0.1%. After reaching the trigger point, the measurement was switched to a shear stress control mode with a constant shear stress (σ=100Pa for the binder, σ=700Pa for the raw material compound). For the heating gradient, the measurement was started in a shear stress control mode with a constant shear stress σ=300Pa. After reaching the trigger point, the measurement was switched to a deformation control mode with a constant deformation γ=0.1%. For the heating gradient, the trigger point was deformation γ=0.1%, except for binder 4-B, where the trigger point was 75°C.

[0212] Viscosity measurement of binder and raw materials Dynamic viscoelastic measurements for viscosity were performed using a NETZSCH Kinexus Pro+ instrument equipped with a Peltier temperature control system, in accordance with EN ISO 3219:1994. Measurements were performed using a 40 mm diameter plate-to-plate configuration. The measurement gap was 0.15 mm. Measurements were performed isothermally at the following temperature: T cross +20K, 100℃, and 130℃. 0.01 to 100s -1Various shear rates were applied and the viscosities at different shear rates were measured. The measurements were carried out in the range of steady flow. The steady state is an indicator of flow that is independent of time. A purely viscous flow leads to a steady state of 1. Viscosity values measured outside the flow that is independent of time are not reliable. Steady state values less than 0.90 or greater than 1.10, preferably less than 0.95 or greater than 1.05, more preferably less than 0.97 or greater than 1.03, are assumed to be no longer fully reliable. In case of doubt, the measurement should be repeated or another suitable measurement setting known per se, for example, a different plate diameter, plate cone shape, or concentric cylinder shape, should be selected.

[0213] DSC measurement DSC measurements were performed using a NETZSCH DSC 214 Polyma instrument. The samples were prepared in NETZSCH aluminum Concavus pans with perforated lids. For this purpose, the samples were heated from -20 °C to 160 °C (180 °C in Examples 2-B and 3-B of Table 3a) at a first heating gradient, then cooled to -20 °C, and finally reheated from -20 °C to 160 °C (180 °C) at a second heating gradient. The heating rate and the cooling rate were each set to 1 K / min. The measurements were carried out using nitrogen of grade 5.0 as purge gas with a gas flow rate of 40 mL / min.

[0214] Examples of production Binder components 1-B to 5-B were produced according to Table 1. Starting compounds 1-F to 5-F of binder components 1-B to 5-B were produced according to Table 2. The melting peak temperature T P , the intersection / "crossover" temperature T cross and the melting enthalpy are shown in Tables 3a and 3b.

[0215]

Table 5

[0216]

Table 6

[0217] [Table 7]

[0218] [Table 8]

[0219] Manufacturing of green parts Laser additive manufacturing Cylindrical specimens were fabricated using laser additive manufacturing with a Formiga P110 (available from EOS GmbH). The raw material compounds 1-F to 5-F listed in Table 2 were used as starting materials.

[0220] For raw material compounds 1-F to 3-F, the laser output was 25W, the powder bed surface temperature was 60°C, and the laser speed was 4450 mm / s. The input energy changed when the hatch spacing was varied (0.13 mm vs. 0.07 mm): with a hatch spacing of 0.13 mm, the input energy was 42.3 mJ / mm². 2 ;When the hatch spacing is 0.07 mm, the input energy is 78.5 mJ / mm² 2 That was the case.

[0221] For raw material compound 4-F, the laser speed was 3000 mm / s, the powder bed surface temperature was 60°C, and the hatch spacing was 0.13 mm. When the laser output was changed (20W vs. 25W), the input energy changed: at a laser output of 25W, the input energy was 64.1 mJ / mm². 2 ;With a laser output of 20W, the input energy is 51.3 mJ / mm² 2 That was the case.

[0222] Notched specimens were fabricated using the laser additive manufacturing method with the Formiga P110 described above, using raw material compounds 1-F to 3-F from Table 2 as starting materials (see "Cylindrical Specimens"). In this specification, the term "notched specimen" refers to a rectangular parallelepiped containing one or more notches, the notches of which may have different widths. Such notched specimens are shown in side and top views in Figures 9 to 11.

[0223] In Figure 9, using raw material compound 1-F as the starting material, with a laser output of 25W, a laser speed of 4450 mm / s, and a hatch spacing of 0.13 mm, the input energy was 42.3 mJ / mm². 2 That was the case.

[0224] In Figure 10, using raw compound 2-F as the starting material, with a laser output of 25W, a laser speed of 4450 mm / s, and a hatch spacing of 0.07 mm, the input energy was 78.5 mJ / mm². 2 That was the case.

[0225] In Figure 11, using raw compound 3-F as the starting material, with a laser output of 25W, a laser speed of 4450 mm / s, and a hatch spacing of 0.07 mm, the input energy was 78.5 mJ / mm². 2 That was the case.

[0226] The purpose of producing such notched test specimens was to obtain dense specimens, i.e., parts, that highly represent the shape of the target part and have almost no caking of the particulate raw material compound, preferably with low laser energy input. The results are shown in Figures 9-11: 42.3 mJ / mm 2 At such low laser energy inputs, only the notched specimen shown in Figure 9 exhibited a dense, highly detailed shape with almost no caking. In contrast, the notched specimens in Figures 10 and 11 showed a low energy input of 78.5 mJ / mm². 2 With this energy input, the density is low, and / or the notch shape is not suitable for caking.

[0227] Molding process Using the raw material compounds 1-F, 2-F, 3-F, and 5-F, test pieces were further fabricated through a molding process. To perform the molding process, a silicone mold with a rectangular parallelepiped cavity of 80×10×5 mm was prepared and preheated to a temperature of 60°C in an oven. The raw material compounds to be investigated were melted at a temperature of 210°C (2-F, 3-F, 5-F) or 170°C (1-F) using the hot glue gun of "REKA Klebetechnik", and pressure of 6 bar was applied to introduce the raw material compounds from the hot glue gun through an open nozzle with a diameter of 4 mm into the rectangular parallelepiped cavity of the preheated mold for press working. After the melted raw material compounds were solidified, the obtained test pieces were taken out from the mold. To obtain test pieces with a uniform surface property, the protruding raw materials were removed by polishing with sandpaper. The test piece made from the raw material compound 1-F is shown in Fig. 8A; the test piece made from the raw material compound 2-F is shown in Fig. 8B; the test piece made from the raw material compound 3-F is shown in Fig. 8C; the test piece made from the raw material compound 5-F is shown in Fig. 8D. In each case, the front and back surfaces are shown.

[0228] Overcast process A rectangular first green part was fabricated using the raw material compound 1-F and overcast with the melted raw material compound 1-F. The rectangular first green part was manufactured by 3D printing using the raw material compound 1-F as described above and placed in a silicone mold with a rectangular parallelepiped cavity of 80×10×5 mm (see Fig. 12A). The mold containing the rectangular first green part was preheated to a temperature of 60°C in an oven. Next, the raw material compound 1F was melted at a temperature of 170°C using the hot glue gun of "REKA Klebetechnik", and pressure of 6 bar was applied to introduce the raw material compound from the hot glue gun through an open nozzle with a diameter of 4 mm into the rectangular parallelepiped cavity of the preheated mold for press working. After solidification, the obtained integral part was taken out from the mold. A photo of the integral part is shown in Fig. 12B; the sintered integral part is shown in Fig. 12C.

[0229] Manufacturing of sintered parts Tensile tests were performed on tensile specimens in accordance with DIN EN ISO 22068. The tensile specimens were produced by additive manufacturing using the Formiga P110 described above, with raw material compound 1-F as shown in Table 2, to obtain green parts. Next, the green parts were subjected to a solvent debinding process and a sintering process. For solvent debinding, the green parts of raw material compound 1-F were immersed in acetone at a temperature of 40°C for 6 hours and then for 16 hours. Sintering was performed with a heating and cooling rate of 5K / min, 380°C for 2 hours, 600°C for 1 hour, 1100°C for 30 minutes, and a final sintering temperature of 1380°C for 2 hours. Five tensile tests were performed in accordance with DIN EN ISO 22068. The results are shown in Table 4.

[0230] [Table 9]

[0231] Rheometer measurements were performed using a Kinexus rheometer (available from NETZSCH), and viscosity measurements were conducted according to EN ISO 3219:1994.

[0232] Tables 5-7 show the results for 100°C, 130°C, or T cross The viscosity values ​​of binder components 1-B to 4-B and raw material compounds 1-F to 4-F, measured at a temperature of +20K, are shown.

[0233] [Table 10]

[0234] [Table 11]

[0235] [Table 12]

[0236] Additional examples

[0237] Table 13

[0238] Table 14

[0239] Table 15

[0240] Table 16

[0241] Table 17

[0242] Table 18

[0243] Table 19

[0244] Table 20

[0245] Table 21

Claims

1. A binder component for raw material compounds used in molding and sintering methods, Based on the total volume of the binder component b), b-i) 3 to 70 volume percent of at least one thermoplastic material selected from polyester, polyolefin, polyolefin wax, polyamide and polyacrylate, b-ii) At least one wax-based material selected from polar waxes, in an amount of 30 to 97 volume percent. Including; The thermoplastic material and the wax-based material differ in their solubility in the solvent. The thermoplastic material has lower solubility than the wax-based material; T ｃｒｏｓｓ is, T Ｐ Compared to this, it is high within a range not exceeding 60K [here, T Ｐ This is the DSC melting peak temperature of binder component b), and T ｃｒｏｓｓ This is the temperature at the intersection of the storage modulus G' curve and the loss modulus G'' curve in the dynamic viscoelastic measurement of binder component b). Binder component.

2. T ｉｎｉｔ and [T Ｐ This shows that the percentage of total enthalpy of melting measured by DSC between +25K is at least 94% (where T ｉｎｉｔ The binder component according to claim 1, where is the initial melting temperature.

3. T Ｐ The binder component according to claim 1 or 2, wherein the temperature is less than 180°C.

4. A viscosity measured at a temperature of 130° C. and a shear rate of 1 s, which is less than 6 Pa·s, for the binder component according to claim 1 or 2. －１ ​

5. A temperature of 110°C and 1 second －１ The binder component according to claim 1 or 2, wherein the viscosity measured at a shear rate is less than 8 Pa·s.

6. A temperature of 100°C and 1 second －１ The binder component according to claim 1 or 2, which exhibits a viscosity of less than 10 Pa·s as measured at a shear rate.

7. The amount of the thermoplastic material b-i) is in the range of 5 to 60 volume percent based on the total volume of the binder component b), and / or The binder component according to claim 1 or 2, wherein the amount of the wax-based material b-ii) is in the range of 40 to 95 volume percent based on the total volume of the binder component b).

8. The binder component according to claim 1 or 2, wherein b-i) is selected from polycaprolactone, polylactide, polyglycolide, poly(hydroxyalkanoate), phthalate, polycarbonate, copolyester, polyethylene, polypropylene, polyolefin copolymer, polyolefin copolymer with nonolefin monomer, modified polyolefin, propylene or homopolymer of higher 1-olefin, copolymer of propylene and ethylene or higher 1-olefin or copolymer of the same, polyamide 12, copolyamide, and polymethyl methacrylate.

9. The binder component according to claim 1 or 2, wherein b-ii) is selected from polyolefin waxes, ester waxes, amide waxes, higher organic acids, higher or polyhydric alcohols, polyethylene glycol, and mixtures thereof.

10. The binder component according to claim 9, wherein b-ii) is selected from aromatic esters and aromatic sulfonamides.

11. A binder component according to claim 1 or 2, comprising a combination of the thermoplastic material b-i) selected from the following table and the wax-based material b-ii). Table 1 Table 2 Table 3 Table 4

12. A particulate raw material compound for use in molding and sintering methods, comprising the following: a) Sinterable non-organic particles dispersed throughout the particulate raw material compound, wherein at least 80% of the particles have a maximum particle size A in the range of 100 nm to 400 μm. ｍａｘ Non-organic particles having a particle size distribution; and b) The binder component according to claim 1 or 2.

13. The particulate raw material compound according to claim 12, wherein the sinterable non-organic particles are selected from the following: a-i) Metal particles selected from iron, stainless steel, steel, copper, bronze, aluminum, tungsten, molybdenum, silver, gold, platinum, titanium, nickel, cobalt, chromium, zinc, niobium, tantalum, yttrium, silicon, magnesium, calcium, and combinations thereof, wherein at least 85% of the particles have a maximum particle size A in the range of 500 nm to 400 μm. ｍａｘ Metal particles having a particle size distribution; a-ii) Ceramic particles selected from oxides; carbides; nitrides; silicates; and combinations thereof, wherein at least 85% of the particles have a maximum particle size A in the range of 200 nm to 25 μm. ｍａｘ Ceramic particles having a particle size distribution; a-iii) Glass particles selected from non-oxide glass; oxide glass; and combinations thereof, wherein at least 85% of the particles have a maximum particle size A in the range of 200 nm to 25 μm. ｍａｘ Glass particles having a particle size distribution; a-iv) More than one combination of sinterable non-organic particles a-i) to a-iii).

14. Sinterable non-organic particles (a) are provided in an amount of 0.70 to 0.99 φ r by volume (where φ ｒ The particulate raw material compound according to claim 12, wherein ( is the critical solid content filling amount by volume).

15. The amount of sinterable non-organic particles (a) is in the range of 20 to 90 volume%, and The particulate raw material compound according to claim 12, wherein the amount of binder component (b) is in the range of 10 to 80 volume percent.

16. Temperature 130°C, shear rate 1 s －１ The particulate raw material compound according to claim 12, wherein the viscosity measured is less than 600 Pa·s.

17. Temperature 110°C, shear rate 1 s －１ The particulate raw material compound according to claim 12, wherein the viscosity measured is less than 800 Pa·s.

18. Temperature 100°C, shear rate 1 s －１ The particulate raw material compound according to claim 12, wherein the viscosity measured is less than 1000 Pa·s.

19. A method that includes the following steps: - A step of fusing multiple particulate raw material compounds according to claim 12 in order to obtain green parts; - A step of partially debinding the green parts by selectively removing the wax-based material (b-ii) in order to obtain brown parts containing sinterable non-organic powder particles (a) bonded together by the thermoplastic material (b-i); and - A process of obtaining sintered parts by sintering brown parts.

20. The method according to claim 19, selected from additive manufacturing; injection molding; press working; and casting.

21. Green parts obtained by fusing multiple particulate raw material compounds according to claim 12.

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