Method for surface treatment and / or manufacturing of medical products, and medical products

Abstract

The present invention relates to a method for the surface treatment and / or production of a medical product, the medical product comprising or consisting of a metal or alloy, the method comprising the following steps: a) electrochemically etching the medical product. Furthermore, the present invention relates to a medical product comprising or consisting of a metal or alloy, the medical product being produced or producible by the above method and / or having at least one of the following characteristics: a pitting potential of -100 mV to 1200 mV, in particular 200 mV to 800 mV, preferably 400 mV to 500 mV, and / or a contact angle of -90° to 140°, in particular 100° to 130°, preferably 110° to 130°, and / or a passivation layer, in particular of chromium oxide, having a thickness of 1 nm to 10 nm, in particular 3 nm to 10 nm, preferably 5 nm to 10 nm, coating at least a part of the surface of the medical product.

Description

[Technical Field]

[0001] The present invention relates to a method for the surface treatment or processing and / or manufacturing of a medical product, and to a medical product.

[0002] Medical products, particularly surgical instruments, generally undergo surface treatment before completion. To this end, the surface of the product may be processed, for example, by slide finishing and / or belt finishing. This may remove defects in the base material and / or casting-related defects, such as decarburized areas, or surface defects, such as pits, scratches, or cracks, which would otherwise adversely affect the corrosion resistance of the product.

[0003] However, belt finishing can create microscopic notches or bumps on the product surface, which can be inverted or flattened in subsequent processing steps. This can result in double material. Additionally, there can be other instances of material transfer, for example, of silicon oxide particles, from the abrasive belt to the product surface. Such material transfer, and the stresses in the medical product associated with machining, can then create or increase inherent stresses in the product. A further problem is that surface defects in the product that are not removed or created in the grinding operation can only be removed to a limited extent in downstream processing steps.

[0004] The matting of medical products can be performed using spherical blasting agents, such as glass beads. This results in plastic deformation of the product surface, which increases in size and roughens it. Generally, glass beads are very hard (Mohs hardness 6) and brittle, resulting in some degree of breakage of the blasting agent over time. As a result, both spherical and broken glass beads strike the product surface during the matting step. Broken glass beads create sharp notches on the product surface, while unbroken glass beads leave spherical indentations on the product surface. As a result of the collisions between broken and unbroken glass beads, there is an interaction between the product surface notched by the broken glass beads and the product surface smoothed by the unbroken glass beads. This, in turn, can result in a double material transfer. In addition to the generation of plastic deformation and corresponding internal stresses, material transfer of the blasting agent to the product surface can occur. This material transfer is particularly pronounced in the notch area, where accumulated glass bead material can remain.

[0005] As an alternative to the blasting agent treatment described above using the example of glass beads, the surface of a medical product can be brushed. For this purpose, the product surface can be processed with a brush disc, for example, using a disc-shaped abrasive pad or nylon fibers in a disc arrangement with abrasive particles. Typically, the brush disc is coated with aluminum oxide and / or silicon oxide particles. The brushing step increases the corrosion resistance of the product surface compared to a matte product surface, but a disadvantage is that a brushed product surface has stronger reflective properties than a matte product surface.

[0006] It is also known that the microstructures or notches formed on the product surface by the double material, and any corresponding creation or increase of built-in stresses in the product, can have a negative effect on the corrosion resistance of the product. For example, in the case of material transfer during belt finishing and / or matting, an additional factor is that the transferred material can create additional microstructures, leading to a weakening of the passivation layer. Summary of the Invention [Problem to be solved by the invention]

[0007] (Objectives and Achievements) The object of the present invention is to provide a method for the surface treatment or processing and / or manufacturing of medical products, which at least in part avoids the drawbacks arising in common types of methods and leads in particular to medical products with high corrosion resistance and reduced reflective properties.

[0008] A further object of the present invention is to provide a corresponding medical product.

[0009] The above mentioned object is achieved according to the present invention by a method having the features of independent claim 1 and by a medical product as claimed in claim 14. Preferred configurations of the method and medical product are the subject of the dependent claims and the description, all claim terms of which are incorporated into the description by express reference. [Means for solving the problem]

[0010] In a first aspect, the present invention relates to a method for the surface treatment or processing and / or manufacture of a medical product, the medical product comprising or consisting of a metal or alloy, the method comprising the steps of: a) electrochemically etching the medical product or the surface of the medical product.

[0011] The expression "medical product" within the context of the present invention may mean a medical end product, preferably a surgical instrument, or a prototype, in particular a semi-finished product, blank or semi-finished product, a medical end product, preferably a surgical instrument, or a component of a medical end product, preferably a surgical instrument.

[0012] The term "alloy" in the context of the present invention should be understood to mean a macroscopically homogeneous metallic material composed of at least two elements (constituents), at least one of which is a metal. Thus, the term "alloy" in the context of the present invention can mean a macroscopically homogeneous metallic material composed of at least two different metals. Alternatively, the term "alloy" in the context of the present invention can mean a macroscopically homogeneous metallic material composed of at least one metal and at least one nonmetal, such as carbon.

[0013] Surprisingly, it has been found that the drawbacks initially encountered in conventional surface treatments of medical products can be partially or even completely avoided by electrochemical etching of the medical product. For example, using the example of surgical instruments, it has been shown that electrochemical etching results in reduced light reflection on the product surface and also increases corrosion resistance. In the case of medical products made of chromium-containing or chromium-alloy stainless steel, the increased corrosion resistance is due, more specifically, to the fact that hexavalent chromium ions enter a dissolved state as a result of the electrochemical etching operation. As a result, the chromium-rich oxide layer on the surface of the medical product is removed, thereby enabling direct attack by the acid used for the electrochemical etching operation on chemical and physical inhomogeneities, such as chromium carbide-containing regions around chromium carbide on the surface of the medical product. This produces a microstructure on the surface of the medical product, particularly in the form of, or preferably with, open etching pits, especially at the location of the former chromium carbide regions. Furthermore, advantageously, decomposition of interface regions, particularly lath and subblock boundaries, is possible, which can result in, in particular, the protrusion of individual martensite laths. As a result, the surface of the medical product appears matte, which particularly advantageously simplifies the user experience of the medical product. For example, this may avoid blinding surgeons in operating rooms. The reduction of chromium-depleted regions at the surface of the medical product also advantageously reduces the risk of forming nucleation sites for pitting corrosion.

[0014] A further advantage is that the electrochemical etching operation can promote the formation of a passivation layer, in particular a thicker passivation layer compared to the prior art, as a result of which the corrosion resistance of the medical product can be further increased.

[0015] A further advantage of electrochemical etching is that compressive and tensile stresses, and / or double and / or overlapping materials, especially on the surface of the medical product, can be largely or completely avoided, which may further reduce the risk of corrosion.

[0016] Additionally, electrochemical etching may advantageously reduce any corrosion-inducing material defects on the surface of the medical product.

[0017] Furthermore, the method of the present invention advantageously leads to a medical product surface that is equally or better cleanable than methods of the common type, and / or to a medical product that is equally or better scratch-resistant, and / or to a medical product that is equally or better mechanically stable, and / or to a medical product that is equally or better tactile, in particular smooth, quality.

[0018] In one embodiment of the invention, a grinding operation, preferably a slide and / or belt grinding, on the surface of the medical product precedes the performance of step a).

[0019] For slide finishing, the medical product is preferably introduced into the container together with the slide finishing body, preferably in the form of a bulk material, or together with an aqueous solution containing the slide finishing body and optionally additives. The optionally provided additives may be selected from the group consisting of anti-rust agents, degreasing agents, pickling agents, separating agents (e.g., polymer beads with a diameter of <1 mm), and mixtures thereof. Such solutions can advantageously pick up and transport the abrasive material formed by the slide finishing body and the abrasive product. Depending on the additives used in each case, further effects, such as corrosion protection, degreasing, and adhesion prevention, can be achieved.

[0020] Vibration or rotational movement of the container creates relative movement between the medical product and the slide finishing body. This results in abrasion of material on the medical product, especially at its edges. The surface image, roughness, material abrasion, and deburring performance of the medical product can advantageously be influenced in a controlled manner by the machine, abrasive body, and optional additives used for slide finishing.

[0021] The slide finish body may include or be made of a material selected from the group consisting of ceramic, plastic, natural materials such as walnut shell, steel, and combinations thereof.

[0022] In principle, the slide finish body can be of regular and / or irregular shape.

[0023] The slide finish body may in particular be free of corners and / or edges, for example in the form of an oval, annular or spherical shape.

[0024] Alternatively or in combination, the slide finishing body may have corners and / or edges. In particular, the slide finishing body may be polyhedral, for example, cubic, cuboidal, prismatic, pyramidal, or parallelepipedal. Furthermore, the slide finishing body may be configured as a rectilinear prism and / or an oblique prism, in particular.

[0025] Alternatively, or in combination, the slide finish body may be conical and / or frustoconical.

[0026] Furthermore, for slide finishing of medical products, a combination of different slide finishing bodies can be used. For example, corner and / or edgeless slide finishing bodies, as well as multi-sided slide finishing bodies can be used. Alternatively, or in combination, different corner and / or edgeless slide finishing bodies and / or different multi-sided slide finishing bodies can be used. With regard to possible configurations and shapes, reference is made entirely to the configurations and shapes described in the preceding paragraphs regarding slide finishing bodies.

[0027] The slide finishing body may also have at least one dimension, particularly at least one average dimension, such as a diameter, particularly an average diameter, and / or a height, particularly an average height, and / or a length, particularly an average length, in the range of 1 mm to 80 mm. Here, the diameter of a spherical slide finishing body in the context of the present invention should be understood to mean twice the radius of a single spherical slide finishing body. In contrast, the diameter of a non-spherical slide finishing body in the context of the present invention should be understood to mean the maximum possible distance between two points that can be taken relative to each other along a line around the perimeter of a single non-spherical slide finishing body. The average dimensions referred to in this paragraph may be determined, for example, by bulk density and / or optical measurements. Slide finishing may also be performed in the form of barrel finishing, vibratory finishing, plunge finishing, drag finishing, centrifugal finishing, or pressure flow wrapping.

[0028] Belt finishing of medical products is preferably carried out using an abrasive belt. For this purpose, it is possible to use an abrasive belt that runs on at least two rolls. The abrasive belt preferably has a particle size of 150 to 1200. Here, the number of particles is determined by the mesh unit of measurement, i.e., the number of meshes in a grid per inch (25.4 mm). Thus, for example, an abrasive with a particle size of 150 will only pass through a sieve with 150 meshes per inch.

[0029] According to the present invention, for example, first slide finishing and then belt finishing can precede the execution of step a). Belt finishing can be advantageous in particular for the treatment of so-called shadow areas of the medical product, but also outside such areas. Shadow areas define areas of the medical product where, due to the geometry and / or configuration of the medical product, slide finishing bodies are not effective on the surface or only have limited effectiveness.

[0030] Alternatively, the surface of the medical product may simply be finished by slide finishing before carrying out step a), which may avoid the formation of notches and / or ridges on the product surface due to belt finishing, and thus may further improve the corrosion resistance of the medical product.

[0031] Alternatively, the surface of the medical product may simply be finished by belt finishing prior to the performance of step a).

[0032] In a further embodiment of the invention, the surface of the medical product is not treated with a blasting agent. As already mentioned, the etching step realized according to the invention advantageously already results in a matt finish of the surface of the medical product, so that any matt finish due to treatment with a blasting agent is not necessary. In this way, it is particularly advantageous to significantly reduce the processing / production time and / or costs for the medical product. Furthermore, in this way, it is possible to avoid the risk of material transfer from the blasting agent to the medical product, which may further improve its corrosion resistance.

[0033] Alternatively, the surface of the medical product can be treated with a blasting agent, preferably before the execution of step a), in particular between the grinding, in particular slide finishing and / or belt finishing, of the surface of the medical product and the execution of step a). The blasting agent used can in particular be a ductile, i.e., non-brittle, blasting agent. The use of such a blasting agent particularly advantageously makes it possible to prevent or at least reduce the generation of notches and / or microstructures, in particular in the form of microscale gaps, on the surface of the medical product. This can avoid or at least reduce the occurrence of local stress peaks in the medical product, and in particular can further improve the corrosion resistance of the medical product. Furthermore, the use of such a blasting agent can advantageously improve the scratch resistance of the medical product. With regard to the grinding, in particular slide finishing and / or belt finishing, of the surface of the medical product referred to in this paragraph, reference is made entirely to the corresponding details given in the preceding description.

[0034] In principle, the blasting agent may comprise or consist of a material selected from the group consisting of metals, metal oxides, alloys, ceramics, plastics, plant materials, sand, and combinations thereof.

[0035] The metal may in particular be aluminium.

[0036] The metal oxide may in particular be aluminum oxide (Al2O3), preferably of the corundum type.

[0037] The plastic may in particular be a urea resin, a phenolic resin, a polyester resin, or a melamine resin.

[0038] The ceramic may in particular be a glass or a mixed ceramic.

[0039] The alloy may be, for example, steel, in particular stainless steel. The alloy is preferably stainless steel, in particular stainless steel. With regard to suitable stainless steels, reference is made to the following specifications:

[0040] The sand may in particular be garnet sand.

[0041] The blasting agent preferably comprises a metal or alloy, or is preferably composed of a metal or alloy. Such a blasting agent has the particular advantage of not breaking and therefore not causing any notches in the surface of the medical product. Moreover, material transfer to the product surface can be reduced or even completely avoided. Overall, this can further improve the corrosion resistance of the medical product and avoid the generation of undesirable internal stresses within the product. Furthermore, such a blasting agent is particularly suitable for increasing the scratch resistance of the medical product.

[0042] Preferably, the blasting agent comprises or is made of steel, in particular stainless steel, such blasting agent being particularly able to provide a clear manifestation of the advantages mentioned in the last paragraph.

[0043] In principle, the blasting agent can be in the form of regularly shaped and / or irregularly shaped, in particular regularly shaped and / or irregularly shaped blasting agent bodies.

[0044] Furthermore, the blasting agent is preferably free of corners and / or edges, in particular in the form of a blasting agent body free of corners and / or edges, which can avoid the generation of notches on the surface of the medical product and thus further improve the corrosion resistance of the medical product.

[0045] In principle, the blasting agent may be ellipsoidal, toroidal, spherical or bead-shaped, or may be in the form of a correspondingly configured blasting agent body.

[0046] The blasting agent is preferably in the form of spherical and / or bead shaped or spherical and / or bead shaped blasting agent bodies.

[0047] Alternatively, or in combination, the blasting agent may have corners and / or edges. In particular, the blasting agent may be polyhedral, for example cubic, cuboidal, prismatic, pyramidal or parallelepipedal, or may take the form of a correspondingly configured blasting agent body. The blasting agent may further take the form of a straight or oblique prism, or may take the form of a correspondingly configured blasting agent body.

[0048] Alternatively, or in combination, the blasting agent may be conical and / or frusto-conical, or may take the form of a conical and / or frusto-conical blasting agent body.

[0049] Alternatively, or in combination, the blasting agent may be in spherical form, for example in the form of a round wire, or in the form of a correspondingly configured blasting agent body.

[0050] Alternatively, or in combination, the blasting agent may be in comminuted form, in particular in the form of comminuted blasting agent bodies.

[0051] Furthermore, the blasting agent or blasting agent body may have at least one dimension, particularly at least one average dimension, such as a diameter, particularly an average diameter, and / or a height, particularly an average height, and / or a length, particularly an average length, in the range of 40 μm to 2000 μm. Here, the diameter of a spherical blasting agent or a spherical blasting agent body in the context of the present invention should be understood to mean twice the radius of the spherical blasting agent or a single spherical blasting agent body. In contrast, the diameter of a non-spherical blasting agent or a non-spherical blasting agent body in the context of the present invention should be understood to mean the maximum possible distance between two points that can be taken relative to each other along a line around the perimeter of the non-spherical blasting agent or a single non-spherical blasting agent body. The average dimensions referred to in this paragraph may be determined, for example, by laser diffraction or sieve analysis.

[0052] The blasting agent or blasting agent body can be accelerated onto the surface of the medical product, for example, by using a jet blasting system, a jet blasting system, or a wheel blasting system. When a pressure jet or jet blasting system is used, pressures of 1 bar to 6 bar can be used.

[0053] In a further embodiment of the invention, the surface of the medical product is not electropolished.

[0054] Alternatively, the surface of the medical product may be electropolished, in particular before the execution of step a), in particular between a grinding operation on the surface of the medical product, in particular slide finishing and / or belt finishing, and between the execution of step a), in particular between the treatment of the surface of the medical product with a blasting agent and the execution of step a), and / or after the execution of step a), in particular between the execution of step a) and the treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution. Electropolishing is generally carried out using an aqueous electrolyte solution. The aqueous electrolyte solution preferably contains a mineral acid or a mineral acid mixture, in particular a mineral acid or a mineral acid mixture selected from the group consisting of phosphoric acid, sulfuric acid, and a mixture of phosphoric acid and sulfuric acid. The aqueous electrolyte solution may also have a phosphoric acid content of 20% to 70% by weight, particularly 30% to 60% by weight, and preferably 40% to 50% by weight, based on the total weight of the aqueous electrolyte solution, and / or a sulfuric acid content of 10% to 70% by weight, particularly 20% to 60% by weight, and preferably 30% to 50% by weight, based on the total weight of the aqueous electrolyte solution. It is further preferred that the surface of the medical product is electropolished at a voltage of 2 V to 10 V, particularly a DC voltage. Here, the voltage may be kept constant or may be varied during electropolishing. It is also preferred that the surface of the medical product is electropolished at a voltage of 5 A / dm 2 ~50A / dm 2More preferably, the surface of the medical product is electropolished at a current density of 1000 kJ / cm. More preferably, the surface of the medical product is electropolished at a temperature of 50°C to 65°C. With regard to the grinding, in particular slide finishing and / or belt finishing, referred to in this paragraph of the surface of the medical product, and the treatment of the surface of the medical product with a blasting agent, reference is made in full to the corresponding details given in the preceding description. With regard to the treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution referred to in this paragraph, reference is made in full to the corresponding details given in the subsequent description.

[0055] Typically, step a) is carried out by anodic removal of the surface of the medical product in an electrolyte solution, which means that the medical product forms the anode in an electrochemical cell.

[0056] In a further embodiment of the invention, step a) is carried out more than once, in particular two, three or four times.

[0057] This may be particularly advantageous in that it may result in uniform processing of the geometric characteristics of the medical product, e.g., the closure of the medical product, without creating a shadow on the closure. The closure of the medical product may be processed in two positions to create only a small shadow. Alternatively, it may be preferable for the medical product to be articulated gradually during the execution of step a).

[0058] Alternatively, step a) may be performed only once.

[0059] In a further embodiment of the invention, step a) is carried out using an acidic aqueous electrolyte solution, in particular comprising a mineral acid or a mixture of mineral acids.

[0060] In a further embodiment of the invention, the mineral acid is selected from the group consisting of phosphoric acid, sulfuric acid, and a mixture of phosphoric acid and sulfuric acid, wherein it has been found that phosphoric acid- and / or sulfuric acid-containing aqueous electrolyte solutions are particularly advantageous for electrochemical etching of surfaces of medical products made of stainless steel, in particular corrosion-resistant stainless steel.

[0061] The aqueous acidic electrolyte solution may also be an aged aqueous acidic electrolyte solution.

[0062] Furthermore, the aqueous acidic electrolyte solution may have a mineral acid content of 50% to 95% by weight, particularly 60% to 95% by weight, and preferably 75% to 95% by weight, based on the total weight of the aqueous acidic electrolyte solution. In particular, the aqueous acidic electrolyte solution may have a phosphoric acid content of 10% to 70% by weight, particularly 20% to 70% by weight, particularly 30% to 60% by weight, and preferably 40% to 50% by weight, and / or a sulfuric acid content of 10% to 70% by weight, particularly 20% to 60% by weight, and preferably 30% to 50% by weight, based on the total weight of the aqueous acidic electrolyte solution.

[0063] The aqueous acidic electrolyte solution may further comprise further additives, such as surfactants.

[0064] The reactivity of the acidic electrolyte aqueous solution can be advantageously controlled by the amount of water in the acidic electrolyte aqueous solution, for example, the amount of water in the acidic electrolyte aqueous solution can be 5 to 25% by weight, particularly 5 to 15% by weight, and preferably 5 to 10% by weight, based on the total weight of the acidic electrolyte aqueous solution.

[0065] In a further embodiment of the invention, step a) is carried out for a period of 6 minutes to 14 minutes, in particular 8 minutes to 12 minutes, preferably 10 minutes.

[0066] In a further embodiment of the present invention, step a) is carried out at / using a voltage, particularly a DC voltage, preferably measured at the anode (of the surface-treated or processed and / or manufactured medical product) of <2 V, particularly 1.2 V to 1.8 V, preferably 1.4 V to 1.7 V, more preferably 1.4 V to 1.5 V or 1.45 V to 1.65 V. In this embodiment of the present invention, the advantages of the present invention are particularly clearly manifested. The voltage is measured at the anode (of the surface-treated or processed and / or manufactured medical product) preferably by a silver-silver chloride electrode. The determined voltage is then converted to a standard hydrogen electrode. Typically, the voltage is established with a current source without knowing what portion of the voltage is applied to the anode and how much is applied to residual resistance (e.g., wire, electrolyte, etc.). In the present invention, it is preferably the precise voltage at the anode that is critical.

[0067] Furthermore, step a) may be performed at / with a constant or varying voltage, in particular a DC voltage. With regard to suitable voltage ranges / values, reference is made to the voltages disclosed in the preceding paragraph.

[0068] In a further embodiment of the invention, step a) is carried out at a voltage of 1.4 A / dm 2 ~2.4A / dm 2 , especially 1.6A / dm 2 ~2.2A / dm 2 , preferably 1.8A / dm 2 ~2.0A / dm 2 The (low) current densities disclosed in this paragraph make it possible to control the etching of the surface of the medical product particularly efficiently over time.

[0069] In a further embodiment of the invention, step a) is carried out at a temperature between 20°C and 90°C, in particular between 50°C and 80°C, preferably between 70°C and 80°C.

[0070] In a further embodiment of the invention, the surface of the medical product is not treated with a passivating acid or a passivating acid-containing solution, in particular after the implementation of step a). As already mentioned, this is because the etching step (step a)) envisaged according to the invention can already particularly advantageously promote the formation of a passivating layer on the surface of the medical product and thus lead to an improvement in the corrosion resistance of the medical product. This configuration of the invention (as well) has the advantage of a clear reduction in processing / manufacturing times and / or costs for the medical product.

[0071] Alternatively, the surface of the medical product may be treated with a passivating acid or a passivating acid-containing solution, in particular a passivating acid-containing aqueous solution, in particular after carrying out step a), in particular after electropolishing of the surface of the medical product.With regard to the electropolishing of the surface of the medical product mentioned in this paragraph, full reference is made to the corresponding details given in the description so far.

[0072] In this way, it is possible to further enhance or promote the formation of a passivation layer on the surface of the medical product, and thus further improve the corrosion resistance of the medical product. In the case of medical products made of chromium-containing or chromium-alloy stainless steel, for example, the passivation layer can cause a thick chromium oxide layer to form on the surface of the medical product.

[0073] The passivating acid used may be, for example, citric acid and / or nitric acid. The passivating acid-containing solution used may be, for example, a citric acid-containing aqueous solution having a citric acid content of 5% to 60% by weight, based on the total weight of the citric acid-containing aqueous solution. Alternatively, the passivating acid-containing solution used may be a nitric acid-containing aqueous solution having a nitric acid content of 5% to 60% by weight, based on the total weight of the nitric acid-containing aqueous solution.

[0074] The use of citric acid is more advantageous than the use of nitric acid both from the standpoint of health and occupational safety. Moreover, in the case of medical products made of chromium-containing or chromium-alloy stainless steel, citric acid makes it possible to achieve a thicker chromium oxide layer than when nitric acid is used, since the latter also reduces the proportion of other alloying elements in the case of such stainless steel.

[0075] During passivation, the medical product can be immersed in, for example, a passivating acid or a passivating acid-containing solution. Alternatively, the passivating acid or a passivating acid-containing solution can be sprayed or poured onto the surface of the medical product.

[0076] Furthermore, the surface of the medical product may be treated with the passivating acid or a solution containing a passivating acid for a period of 2 to 120 minutes, in particular 5 to 60 minutes, preferably 10 to 30 minutes.

[0077] Furthermore, the surface of the medical product may be treated with a passivating acid or a solution containing a passivating acid within a temperature range of 20°C to 80°C, in particular 30°C to 65°C, preferably 50°C to 60°C.

[0078] Furthermore, a cleaning and / or degreasing operation on the surface of the medical product may be carried out between step a) and the treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution, in particular between an electropolishing operation on the surface of the medical product and the treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution.With regard to the electropolishing of the surface of the medical product mentioned in this paragraph, full reference is made to the corresponding details given in the preceding description.

[0079] In a further embodiment of the present invention, step b) of packing and / or marking, in particular labeling, the medical product follows the performance of step a), in particular after electropolishing of the surface of the medical product, in particular after treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution. Preferably, step ab) of sterilizing, in particular steam sterilizing, the medical product is performed between steps a) and b), in particular between electropolishing of the surface of the medical product and step b), in particular between treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution. Alternatively, it may be preferred that step c) of sterilizing, in particular steam sterilizing, the medical product follows the performance of step b). With regard to the electropolishing of the surface of the medical product referred to in this paragraph and the treatment of the surface of the medical product with a passivating acid or a passivating acid-containing solution referred to in this paragraph, reference is made entirely to the corresponding details given in the preceding description.

[0080] In a further embodiment of the invention, the medical product comprises or is made of steel, preferably stainless steel.

[0081] The expression "stainless steel" within the context of the present invention (in accordance with EN 10020) is understood to mean alloyed or non-alloyed steels with a certain level of purity, for example a mass fraction of sulfur and / or phosphorus ≦0.025%, in particular <0.025%.

[0082] The stainless steel may include at least one alloying element selected from the group consisting of chromium, nickel, molybdenum, titanium, niobium, tungsten, vanadium, cobalt, and combinations thereof, among others.

[0083] In particular, the stainless steel may have a chromium mass fraction of 10% to 25%.

[0084] More preferably, the stainless steel is a rust-resistant or corrosion-resistant stainless steel.

[0085] More preferably, the stainless steel is a chromium-containing or chromium-alloy stainless steel. Preferably, the stainless steel is a chromium-containing corrosion-resistant stainless steel or a chromium-alloy corrosion-resistant stainless steel.

[0086] Furthermore, the stainless steel may be, inter alia, a martensitic, ferritic, or austenitic stainless steel.

[0087] Preferably, the stainless steel is a martensitic corrosion-resistant stainless steel according to ISO 7153-1, in particular a so-called carbon martensite, i.e. a corrosion-resistant stainless steel having chromium and carbon as the main alloying elements, or a so-called nickel martensite, i.e. a corrosion-resistant stainless steel having nickel as the main alloying element.

[0088] In particular, the stainless steel may be a martensitic stainless steel having a chromium proportion by mass of 10.5% to 13% and / or a carbon proportion by mass of 0.2% to 1%.

[0089] Alternatively, the stainless steel may be an austenitic stainless steel, in particular having a chromium proportion by weight between 16% and 21% and / or a carbon proportion by weight between 0.02% and 0.12%.

[0090] Alternatively, the stainless steel may be a ferritic stainless steel, in particular with a chromium mass proportion of 12% to 18% and / or a carbon mass proportion of <0.2%.

[0091] For example, the stainless steel may be stainless steel with the short material designation X12Cr13 (material number 1.4006), which is a martensitic stainless steel with a carbon mass percentage of 0.08% to 0.15%, a chromium mass percentage of 11.5% to 13.5%, and a nickel mass percentage of ≦0.75%.

[0092] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X12CrS13 (material number 1.4005), which has a carbon mass percentage of 0.08% to 0.15%, a chromium mass percentage of 12.0% to 14.0%, and a molybdenum mass percentage of ≦0.60%, and optionally a sulfur mass percentage of 0.15% to 0.35%.

[0093] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X20Cr13 (material number 1.4021), which has a carbon mass percentage of 0.16% to 0.25% and a chromium mass percentage of 12.0% to 14.0%.

[0094] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X15Cr13 (material number 1.4024), which has a carbon mass percentage of 0.12% to 0.17% and a chromium mass percentage of 12.0% to 14.0%.

[0095] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X30Cr13 (material number 1.4028), which has a carbon mass percentage of 0.26% to 0.35% and a chromium mass percentage of 12.0% to 14.0%.

[0096] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X46Cr13 (material number 1.4034), which has a carbon mass percentage between 0.43% and 0.50% and a chromium mass percentage between 12.5% and 14.5%.

[0097] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X50CrMoV15 (material number 1.4116), which has a mass percentage of carbon between 0.45% and 0.55%, a mass percentage of chromium between 14.0% and 15.0%, a mass percentage of molybdenum between 0.50% and 0.80%, and a mass percentage of vanadium between 0.10% and 0.20%.

[0098] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X17CrNi16-2 (material number 1.4057), which has a mass percentage of carbon between 0.12% and 0.22%, a mass percentage of chromium between 15.0% and 17.0%, and a mass percentage of nickel between 1.5% and 2.5%.

[0099] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X39CrMo17-1 (material number 1.4122), which has a carbon content of 0.33% to 0.45%, a chromium content of 15.5% to 17.5%, a molybdenum content of 0.8% to 1.3%, and a nickel content of ≦1.0%.

[0100] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X14CrMoS17 (material number 1.4104), which has a mass percentage of carbon between 0.10% and 0.17%, a mass percentage of chromium between 15.5% and 17.5%, a mass percentage of molybdenum between 0.20% and 0.60%, and a mass percentage of sulfur between 0.15% and 0.35%.

[0101] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X3CrNiMoV13-4 (material number 1.4313), which has a mass percentage of carbon ≦0.05%, a mass percentage of chromium between 12.0% and 14.0%, a mass percentage of molybdenum between 0.30% and 0.70%, and a mass percentage of nickel between 3.5% and 4.5%.

[0102] Alternatively, the stainless steel may be a martensitic corrosion-resistant stainless steel with the short material designation X4CrNiMo16-5-1 (material number 1.4418), which has a mass percentage of carbon ≦0.06%, a mass percentage of chromium between 15.0% and 17.0%, a mass percentage of molybdenum between 0.80% and 1.50%, and a mass percentage of nickel between 4.0% and 6.0%.

[0103] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X65Cr13, which has a carbon content of 0.58% to 0.70%, a chromium content of 12.5% to 14.5%, a manganese content of ≦1.00%, a silicon content of ≦1.00%, a phosphorus content of 0.04%, and a sulfur content of 0.015%.

[0104] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X30CrMoN15-1 (material number: 1.4108), which has a mass fraction of carbon between 0.25% and 0.35%, a mass fraction of chromium between 14.0% and 16.0%, a mass fraction of molybdenum between 0.85% and 1.10%, a mass fraction of nickel between 0.50%, a mass fraction of manganese between 1.00%, a mass fraction of silicon between 1.00%, and a mass fraction of nitrogen between 0.03% and 0.50%.

[0105] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X70CrMo15 (material number: 1.4109), which has a carbon content of 0.60% to 0.75%, a chromium content of 14.0% to 16.0%, a molybdenum content of 0.40% to 0.80%, a manganese content of ≦1.00%, a silicon content of ≦0.70%, a phosphorus content of 0.04%, and a sulfur content of 0.015%.

[0106] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X90CrMoV18 (material number: 1.4112), which has a mass percentage of carbon of 0.90%, a mass percentage of chromium of 17% to 19%, and a mass percentage of molybdenum of 0.90%.

[0107] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X38CrMoV15 (material number: 1.4117), which has a mass percentage of carbon of 0.38%, a mass percentage of chromium of 14% to 15%, and a mass percentage of molybdenum of 0.50%.

[0108] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X150CrMo17 (material number: 1.4125), which has a mass percentage of carbon of 1.10%, a mass percentage of chromium of 17%, and a mass percentage of molybdenum of 0.60%.

[0109] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X22CrMoNiS13-1 (material number: 1.4121), which has a mass percentage of carbon between 0.20% and 0.25%, a mass percentage of chromium between 12.0% and 14.0%, a mass percentage of molybdenum between 1.00% and 1.50%, a mass percentage of nickel between 0.80% and 1.20%, a mass percentage of manganese between 1.00% and 1.50%, a mass percentage of silicon less than or equal to 1.00%, a mass percentage of phosphorus between 0.045%, and a mass percentage of sulfur between 0.15% and 0.25%.

[0110] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X40CrMoVN16-2 (material number: 1.4123), which has a mass percentage of carbon between 0.35% and 0.50%, a mass percentage of chromium between 14.0% and 16.0%, a mass percentage of molybdenum between 1.00% and 2.50%, a mass percentage of nickel between 0.5%, a mass percentage of manganese less than or equal to 1.00%, a mass percentage of silicon less than or equal to 1.00%, a mass percentage of phosphorus between 0.04% and 0.015%.

[0111] Alternatively, the stainless steel may be a martensitic stainless steel with the short material designation X105CrMo17 (material number: 1.4125), which has a mass percentage of carbon between 0.95% and 1.20%, a mass percentage of chromium between 16.0% and 18.0%, a mass percentage of molybdenum between 0.04% and 0.80%, a mass percentage of manganese not more than 1.00%, a mass percentage of silicon not more than 1.00%, a mass percentage of phosphorus not more than 0.040%, and a mass percentage of sulfur not more than 0.015%.

[0112] Alternatively, the stainless steel may be a precipitation-hardened, corrosion-resistant stainless steel with the short material designation X5CrNiCuNb16-4 (material number: 1.4542), which has a carbon content of ≦0.07%, a chromium content of 15.0% to 17.0%, a molybdenum content of ≦0.60%, a nickel content of 3.0% to 5.0%, a copper content of 3.0% to 5.0%, and a niobium content of 0.45% or less.

[0113] Alternatively, the stainless steel may be a precipitation-hardened, corrosion-resistant stainless steel with the short material designation X7CrNiAl17-7 (material number: 1.4568), which has a mass percentage of carbon ≦0.09%, a mass percentage of chromium between 16.0% and 18.0%, a mass percentage of nickel between 6.5% and 7.8%, and a mass percentage of aluminum between 0.70% and 1.50%.

[0114] Alternatively, the stainless steel may be a precipitation-hardened, corrosion-resistant stainless steel with the short material designation X5CrNiMoCuNb14-5 (material number: 1.4594), which has a mass percentage of carbon ≦0.07%, a mass percentage of chromium between 13.0% and 15.0%, a mass percentage of molybdenum between 1.20% and 2.00%, a mass percentage of nickel between 5.0% and 6.0%, a mass percentage of copper between 1.20% and 2.00%, and a mass percentage of niobium between 0.15% and 0.60%.

[0115] Alternatively, the stainless steel may be a precipitation-hardened, corrosion-resistant stainless steel with the short material designation X3CrNiTiMb12-9 (material number: 1.4543), which has a carbon content of ≦0.03%, a chromium content of 11.0% to 12.5%, a molybdenum content of ≦0.50%, a nickel content of 3.00% to 5.00%, a titanium content of ≦0.90% to 1.40%, a copper content of 1.50% to 2.50%, a niobium content of 0.10% to 0.50%, a manganese content of 0.50%, a silicon content of 0.50%, a phosphorus content of ≦0.02%, and a sulfur content of ≦0.015%.

[0116] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X2CrNi12 (material number: 1.4003), which has a carbon mass percentage of ≦0.03%, a chromium mass percentage of 10.5% to 12.5%, a nickel mass percentage of 0.3% to 1.00%, and a nitrogen mass percentage of ≦0.03%.

[0117] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X2CrNi12 (material number: 1.4512), which has a carbon mass percentage of ≦0.03%, a chromium mass percentage of 10.5% to 12.5%, and a titanium mass percentage of 0.65% or less.

[0118] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X6Cr17 (material number: 1.4016), which has a carbon mass percentage of ≦0.08% and a chromium mass percentage of 16.0% to 18.0%.

[0119] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X3CrTi17 (material number: 1.4510), which has a carbon mass percentage of ≦0.05%, a chromium mass percentage of 16.0% to 18.0%, and a titanium mass percentage of 0.80% or less.

[0120] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X6CrMoS17 (material number: 1.4105), which has a mass percentage of carbon ≦0.08%, a mass percentage of chromium 16.0% to 18.0%, a mass percentage of molybdenum 0.20% to 0.60%, and a mass percentage of sulfur 0.15% to 0.35%.

[0121] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X3CrNb17 (material number: 1.4511), which has a carbon mass percentage of ≦0.05%, a chromium mass percentage of 16.0% to 18.0%, and a niobium mass percentage of ≦1.00%.

[0122] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X2CrTiNb18 (material number: 1.4509), which has a carbon content of ≦0.03%, a chromium content of 17.5% to 18.5%, a niobium content of ≦1.00%, and a titanium content of 0.10% to 0.60%.

[0123] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X6CrMo17-1 (material number: 1.4113), which has a carbon mass percentage of ≦0.08%, a chromium mass percentage of 16.0% to 18.0%, and a molybdenum mass percentage of 0.90% to 1.40%.

[0124] Alternatively, the stainless steel may be a ferritic corrosion-resistant stainless steel with the short material designation X2CrMoTi18-2 (material number: 1.4521), which has a mass percentage of carbon ≦0.025%, a mass percentage of chromium between 17.0% and 20.0%, a mass percentage of molybdenum between 1.80% and 2.50%, and a mass percentage of titanium below 0.80%.

[0125] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrNi22-2 (material number: 1.4062), which has a mass percentage of carbon ≦0.03%, a mass percentage of chromium 21.5% to 24.0%, a mass percentage of molybdenum ≦0.45%, a mass percentage of nickel 1.00% to 2.90%, and a mass percentage of nitrogen 0.16% to 0.28%.

[0126] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrMnNiN21-5-1 (material number: 1.4162), which has a mass percentage of carbon ≦0.04%, a mass percentage of chromium 21.0% to 22.0%, a mass percentage of molybdenum 0.10% to 0.80%, a mass percentage of nickel 1.35% to 1.70%, a mass percentage of manganese 4.0% to 6.0%, a mass percentage of nitrogen 0.20% to 0.25%, and a mass percentage of copper 0.10% to 0.80%.

[0127] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrNiN23-4 (material number: 1.4362), which has a mass percentage of carbon ≦0.03%, a mass percentage of chromium between 22.0% and 24.0%, a mass percentage of molybdenum between 0.10% and 0.60%, a mass percentage of nickel between 3.5% and 5.5%, and a mass percentage of copper between 0.10% and 0.60%.

[0128] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrNiMoN22-5-3 (material number: 1.4462), which has a mass percentage of carbon ≦0.03%, a mass percentage of chromium 21.0% to 23.0%, a mass percentage of molybdenum 2.5% to 3.5%, a mass percentage of nickel 4.5% to 6.5%, and a mass percentage of nitrogen 0.10% to 0.22%.

[0129] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrNiMnMoCuN24-4-3-2 (material number: 1.4662), which has a mass percentage of carbon ≦0.03%, a mass percentage of chromium 23.0% to 25.0%, a mass percentage of molybdenum 1.00% to 2.00%, a mass percentage of nickel 3.0% to 4.5%, a mass percentage of manganese 2.5% to 4.0%, and a mass percentage of copper 0.10% to 0.80%.

[0130] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrNiMoN25-7-4 (material number: 1.4410), which has a mass percentage of carbon ≦0.03%, a mass percentage of chromium 24.0% to 26.0%, a mass percentage of molybdenum 3.0% to 4.5%, a mass percentage of nickel 6.0% to 8.0%, and a mass percentage of nitrogen 0.24% to 0.35%.

[0131] Alternatively, the stainless steel may be an austenitic-ferritic corrosion-resistant stainless steel with the short material designation X2CrNiMoCuWN25-7-4 (material number: 1.4501), which has a mass percentage of carbon ≦0.03%, a mass percentage of chromium 24.0% to 26.0%, a mass percentage of molybdenum 3.0% to 4.0%, a mass percentage of nickel 6.0% to 8.0%, a mass percentage of copper 0.50% to 1.00%, a mass percentage of tungsten 0.50% to 1.00%, and a mass percentage of nitrogen 0.20% to 0.30%.

[0132] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNiMo18-15-3 (material number: 1.4441), which has a carbon content of 0.030% or less, a chromium content of 17.0% to 19.0%, a molybdenum content of 2.70% to 3.0%, a nickel content of 13.0% to 15.0%, a manganese content of 2.00% or less, a copper content of 0.50% or less, a silicon content of 0.75% or less, a phosphorus content of 0.025% or less, a sulfur content of 0.003% or less, and a nitrogen content of 0.10% or less.

[0133] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X5CrNi18-10 (material number: 1.4301), which has a mass percentage of carbon ≦0.07%, a mass percentage of chromium 17.5% to 19.5%, a mass percentage of nickel 8.0% to 10.5%, and a mass percentage of nitrogen ≦0.11%.

[0134] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X4CrNi18-12 (material number: 1.4303), which has a mass percentage of carbon ≦0.06%, a mass percentage of chromium 17.0% to 19.0%, a mass percentage of nickel 11.0% to 13.0%, and a mass percentage of nitrogen ≦0.11%.

[0135] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X8CrNiS18-9 (material number: 1.4305), which has a carbon content of ≦0.10%, a chromium content of 17.0% to 19.0%, a nickel content of 8.0% to 10.0%, a sulfur content of 0.15% to 0.35%, and a copper content of ≦1.00%.

[0136] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNi19-11 (material number: 1.4306), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium 18.0% to 20.0%, a mass percentage of nickel 10.0% to 12.0%, and a mass percentage of nitrogen ≦0.11%.

[0137] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNi18-9 (material number: 1.4307), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium 17.5% to 19.5%, a mass percentage of nickel 8.0% to 10.5%, and a mass percentage of nitrogen ≦0.11%.

[0138] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNi18-10 (material number: 1.4311), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium between 17.5% and 19.5%, a mass percentage of nickel between 8.5% and 11.5%, and a mass percentage of nitrogen between 0.12% and 0.22%.

[0139] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X6CrNiTi18-10 (material number: 1.4541), which has a carbon mass percentage of ≦0.08%, a chromium mass percentage of 17.0% to 19.0%, a nickel mass percentage of 9.0% to 12.0%, and a titanium mass percentage of 0.70% or less.

[0140] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X6CrNiNb18-10 (material number: 1.4550), which has a mass percentage of carbon ≦0.08%, a mass percentage of chromium between 17.0% and 19.0%, a mass percentage of nickel between 9.0% and 12.0%, and a mass percentage of niobium up to 1.00%.

[0141] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X3CrNiCu18-9-4 (material number: 1.4567), which has a mass percentage of carbon ≦0.04%, a mass percentage of chromium 17.0% to 19.0%, a mass percentage of nickel 8.5% to 10.5%, and a mass percentage of copper 3.0% to 4.0%.

[0142] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X10CrNi18-8 (material number: 1.4310), which has a carbon content of 0.05% to 0.15%, a chromium content of 16.0% to 19.0%, a molybdenum content of ≦0.80%, and a nickel content of 6.0% to 9.5%.

[0143] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X5CrNiMo17-12-2 (material number: 1.4401), which has a mass percentage of carbon ≦0.07%, a mass percentage of chromium 16.5% to 18.5%, a mass percentage of molybdenum 2.00% to 2.50%, a mass percentage of nickel 10.0% to 13.0%, and a mass percentage of nitrogen ≦0.10%.

[0144] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNiMo17-12-2 (material number: 1.4404), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium 16.5% to 18.5%, a mass percentage of molybdenum 2.00% to 2.50%, a mass percentage of nickel 10.0% to 13.0%, and a mass percentage of nitrogen ≦0.10%.

[0145] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X6CrNiMoTi17-12-2 (material number: 1.4571), which has a mass percentage of carbon ≦0.08%, a mass percentage of chromium between 16.5% and 18.5%, a mass percentage of molybdenum between 2.00% and 2.50%, a mass percentage of nickel between 10.5% and 13.5%, and a mass percentage of titanium up to 0.70%.

[0146] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNiMoN17-13-3 (material number: 1.4429), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium 16.5% to 18.5%, a mass percentage of molybdenum 2.5% to 3.0%, a mass percentage of nickel 11.0% to 14.0%, and a mass percentage of nitrogen 0.12% to 0.22%.

[0147] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNiMo18-14-3 (material number: 1.4435), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium 17.0% to 19.0%, a mass percentage of molybdenum 2.5% to 3.0%, a mass percentage of nickel 12.5% to 15.0%, and a mass percentage of nitrogen ≦0.10%.

[0148] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X3CrNiMo17-13-3 (material number: 1.4436), which has a mass percentage of carbon ≦0.05%, a mass percentage of chromium 16.5% to 18.5%, a mass percentage of molybdenum 2.5% to 3.0%, a mass percentage of nickel 10.5% to 13.0%, and a mass percentage of nitrogen ≦0.10%.

[0149] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNiMoN17-13-5 (material number: 1.4439), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium between 16.5% and 18.5%, a mass percentage of molybdenum between 4.0% and 5.0%, a mass percentage of nickel between 12.5% and 14.5%, and a mass percentage of nitrogen between 0.12% and 0.22%.

[0150] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X1NiCrMoCu25-20-5 (material number: 1.4539), which has a mass percentage of carbon ≦0.020%, a mass percentage of chromium 19.0% to 21.0%, a mass percentage of molybdenum 4.0% to 5.0%, a mass percentage of nickel 24.0% to 26.0%, a mass percentage of copper 1.20% to 2.00%, and a mass percentage of nitrogen ≦0.15%.

[0151] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X2CrNiMnMoNbN25-18-5-4 (material number: 1.4565), which has a mass percentage of carbon ≦0.030%, a mass percentage of chromium 24.0% to 26.0%, a mass percentage of molybdenum 4.0% to 5.0%, a mass percentage of nickel 16.0% to 19.0%, a mass percentage of manganese 5.0% to 7.0%, a mass percentage of nitrogen 0.30% to 0.60%, and a mass percentage of niobium ≦0.15%.

[0152] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X1NiCrMoCuN25-20-7 (material number: 1.4529), which has a mass percentage of carbon ≦0.020%, a mass percentage of chromium 19.0% to 21.0%, a mass percentage of molybdenum 6.0% to 7.0%, a mass percentage of nickel 24.0% to 26.0%, a mass percentage of copper 0.50% to 1.50%, and a mass percentage of nitrogen 0.15% to 0.25%.

[0153] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X1CrNiMoCuN20-18-7 (material number: 1.4547), which has a mass percentage of carbon ≦0.020%, a mass percentage of chromium 19.5% to 20.5%, a mass percentage of molybdenum 6.0% to 7.0%, a mass percentage of nickel 17.5% to 18.5%, a mass percentage of copper 0.50% to 1.00%, and a mass percentage of nitrogen 0.18% to 0.25%.

[0154] Alternatively, the stainless steel may be an austenitic corrosion-resistant stainless steel with the short material designation X1CrNiMoCuN24-22-8 (material number: 1.4652), which has a mass percentage of carbon ≦0.020%, a mass percentage of chromium 23.0% to 25.0%, a mass percentage of molybdenum 7.0% to 8.0%, a mass percentage of nickel 21.0% to 23.0%, a mass percentage of manganese 2.0% to 4.0%, and a mass percentage of nitrogen 0.45% to 0.5%.

[0155] In a further embodiment of the invention, the medical product is a medical device, preferably a surgical device. The device may be a reusable device or a disposable device.

[0156] Additionally, the device may be a minimally invasive device, ie, a device that can be used in minimally invasive surgery.

[0157] The surgical instrument may be selected from the group consisting of a dilating instrument, a grasping instrument, a clamping instrument, a cutting instrument, a suturing device, an endoscope, and a combination instrument, among others.

[0158] The expansion device can be, for example, a surgical hook, a retractor, a wound spreader, a sternal spreader, a wound closure, a speculum, or a trocar sleeve.

[0159] The grasping device may be, for example, a set of tweezers, a clamp, a needle holder, or a set of grasping forceps.

[0160] The clamping device may be, for example, a soft clamp, or a pre-clamp, particularly for temporary occlusion of bowel and small ducts.

[0161] The cutting instrument may be, for example, a scalpel, a knife, a set of scissors, a set of bifurcated forceps, a set of bone fragment forceps, a set of ring forceps, an electrocautery knife, turbinate scissors, a cautery tool, or an ultrasonic knife.

[0162] The suturing device may be, inter alia, a stapler or staple remover.

[0163] The combined instrument can be, for example, an endostapler or stapler that clamps and precisely cuts hollow organs at the same time. Additionally, the combined instrument can be a combined needle holder that can both grasp and cut as a universal suturing device.

[0164] Additionally, the surgical instrument may be a hammer.

[0165] Furthermore, the surgical instrument may be a chisel, in particular a flat chisel or a gouge such as a bone gouge, or a curette, in particular a bone curette.

[0166] Additionally, the surgical instrument may be a probe.

[0167] Additionally, the surgical instrument may be a bone punch.

[0168] Additionally, the surgical instrument may be a lever or elevator, or a raspati.

[0169] In a second aspect, the present invention relates to a medical product comprising or consisting of a metal or alloy, which medical product is produced or producible by a method according to the first aspect of the invention and / or which has at least one of the following characteristics: - a pitting potential (measured against a standard hydrogen electrode) of 100 mV to 1200 mV, in particular 200 mV to 800 mV, preferably 400 mV to 500 mV, and / or a contact angle of -90° to 140°, in particular 100° to 130°, preferably 110° to 130°, and / or - a passivation layer, in particular of chromium oxide, having a thickness of 1 nm to 10 nm, in particular 3 nm to 10 nm, preferably 5 nm to 10 nm, coating at least a part, in particular only partly or completely, of the surface of the medical product.

[0170] The aforementioned pitting potential and contact angle are particularly advantageous with respect to corrosion resistance of medical products.

[0171] The expression "pitting potential" within the context of the present invention is understood to mean the electrochemical potential that can be determined using an electrochemical cell using a three-electrode configuration. The pitting potential is characterized by a sudden increase in current, which represents the breakdown of the passive layer at the onset of pitting corrosion. An increase in the pitting potential leads to improved corrosion resistance through a reduced tendency for pitting corrosion.

[0172] The pitting potential can be measured according to ASTM G5-13-1 or DIN EN ISO10993-15.

[0173] The expression "contact angle" within the context of the present invention should be understood to mean the angle formed by a droplet of liquid on the surface of the medical product relative to the surface of the medical product. A reduced contact angle corresponds to reduced contact of the droplet on the surface of the medical product. A reduced contact angle particularly advantageously leads to improved corrosion resistance and cleanability of the medical product.

[0174] Contact angles can be measured according to ASTM D7334-08. Alternatively, contact angle measurements can be performed using a contact angle measurement instrument from dataPhysics (Contact Angle System OCA15 Plus) using a 0.9% sodium chloride solution (B. Braun) with a drop volume of 1 μl. For contact angle measurements, samples in this case can be washed in a normal manufacturing process and washed with deionized water in an ultrasonic bath for 5 minutes before measurement, and immediately before measurement, the samples are rinsed with deionized water and blown dry with oil-free compressed air.

[0175] The medical product is preferably a medical device, preferably a surgical device.

[0176] With regard to further features and advantages of the medical product, in order to avoid repetition, reference is made entirely to the details given in the context of the first aspect of the invention. The features and advantages described therein with respect to the method and medical product are also applicable mutatis mutandis to the medical product according to the second aspect of the invention.

[0177] Further features and advantages of the present invention will be apparent from the claims and the description of preferred embodiments, with reference to the following examples, where the features of the present invention can be implemented individually, by themselves, or in combination with one another. The embodiments described below serve to further clarify the present invention, without the present invention being limited thereto. DETAILED DESCRIPTION OF THE INVENTION

[0178] Examples Section Surface treatment of surgical instruments or representative samples thereof by the method of the present invention

[0179] The specimens used, as well as the surgical instruments, were produced using the same martensitic stainless steel (X20Cr13) and with the same manufacturing steps and parameters.

[0180] SEM / EDX analysis (foreign and double materials) was performed on the instrument and on the sample plaques.

[0181] Potentiodynamic tests (pitting corrosion potential) were also performed on the instrument and sample plaques.

[0182] Contact angle measurements (contact angle) were performed on sample plaques (flat surfaces without shadows).

[0183] Gloss measurements (gloss) were performed on sample plaques (flat surface without shadow).

[0184] 3D laser confocal microscopy (roughness depth) was performed on the sample plaque (flat surface without shadows).

[0185] Prior to surface treatment, surgical instruments according to the current production chain of surgical instruments, corrosion specimens, and sample plaques were molded and heat treated.

[0186] For subsequent surface treatment, the surgical instruments (BH110R clamps), corrosion specimens, and sample plaques were treated with a slide polish in an acidic solution for a period of 4 hours, and then polished with a slide polish in an aqueous solution for a period of 1 hour.

[0187] The surgical instruments, corrosion specimens, and sample plaques were then electrochemically etched. For this purpose, the parts were immersed in an aqueous acidic electrolyte solution with mineral acid contents of 11% by weight phosphoric acid and 61% by weight sulfuric acid at a temperature of 40°C, and a DC voltage was applied for 10 minutes to result in a voltage of 1.5 V at the anode, where 2.0 A / dm 2 A current density of was established.

[0188] Finally, the surgical instruments, corrosion specimens, and sample plaques were passivated. For this purpose, the parts were immersed in a 10% by weight citric acid solution at a temperature of 60°C for 10 minutes. Afterwards, the parts were immersed in ethanol and washed.

[0189] After production, the surface formation of the device and sample plaques was examined via scanning electron microscopy with an energy dispersive X-ray spectroscopy unit. SEM examination showed that etched trenches were distributed substantially randomly on the surface, with only a few localized at grain boundaries. These were on the order of approximately 5 μm in size range. The chemical composition was homogeneous, with a chromium level approximately 0.1 wt. % less than the starting material. This was due to chromium carbides leached out of the surface.

[0190] Additionally, the surface topography of the device and sample plaques was evaluated by 3D laser confocal microscopy and metallographic sections. 3D laser confocal measurements allowed for the determination of an average roughness depth of 0.5 μm, which was attributed to the depth of the etched trenches, which, according to the metallographic investigation, was in the range of 1–3 μm.

[0191] The change in the reflective properties was examined by gloss measurements on the test plaques. A clear reduction in gloss was found, with values of 3.7 gloss units (20°) and 21.6 gloss units (60°). It could therefore be determined that the reflective properties were strongly matte.

[0192] Analysis of wetting by liquids was carried out by contact angle measurements on test plaques, where an average contact angle of 116.3° was determined.

[0193] Finally, the electrochemical / corrosion properties of the formed surface were examined by potentiodynamic polarization measurements on the corrosion specimens, and the pitting potential was confirmed. For comparison with the measurements on the test specimens, the pitting potential was measured on laboratory equipment, where the results on the test specimens were confirmed. A pitting potential of 475 mV was recorded.

[0194] 2. Surface treatment of surgical instruments by common methods

[0195] The surgical instruments (BH110R clamps), corrosion specimens, and sample plaques were first treated with slide polish for a period of 4 hours. Afterwards, the surgical instruments and specimens were polished for a period of 1 hour.

[0196] The surgical instruments and specimens were then treated by blasting. For this purpose, glass beads with an average diameter of 40 μm to 70 μm were used. Blasting was carried out in a spray blasting system at a pressure of 4 bar.

[0197] The surgical instruments and specimens were then passivated. For this purpose, a 10% citric acid solution was used. Passivation was carried out for a period of 10 minutes at a temperature of 55°C.

[0198] As a result of the surface preparation of the surgical instruments and specimens, duplicate or overlapping materials were detectable in many instances. Additionally, 1.4% foreign material transfer was detected. The roughness depth was in the region of 0.151 μm. Furthermore, the sample platelets had a contact angle of 66.0°. The gloss was found to be 41.9 gloss units (20°) and 159.8 gloss units (60°), and therefore could be described as slightly matte. The pitting potential of the corroded specimens was 386 mV.

[0199] 3. Conclusion The above comparison of the method of the present invention and methods of the general type shows that the method of the present invention leads to a more corrosion resistant product with a very low reflectance (gloss). The following items are elements that are claimed in the international application: (Item 1) 1. A method for the surface treatment and / or production of a surgical instrument prototype or component, said prototype or component comprising or consisting of a metal or alloy, said method comprising the steps of: a) electrochemically etching the master or component; Step a) is a voltage of 1.4 V to 1.7 V and / or 1.6 A / dm applied to the anode. 2 ~2.2A / dm 2 The method is carried out at a current density of (Item 2) 2. The method according to item 1, characterized in that a grinding operation, preferably a slide finishing and / or a belt finishing, on the surface of the master or component of the surgical instrument precedes the execution of step a). (Item 3) 3. The method according to claim 1 or 2, characterized in that the surface of the prototype or component of the surgical instrument has not been treated with a blasting agent and / or has not been electropolished. (Item 4) 4. The method according to any one of items 1 to 3, characterized in that step a) is carried out more than once, in particular 2, 3 or 4 times. (Item 5) 5. The method according to any one of items 1 to 4, characterized in that step a) is carried out using an acidic aqueous electrolyte solution, in particular comprising a mineral acid or a mixture of mineral acids. (Item 6) 6. The method according to claim 5, wherein the mineral acid is selected from the group consisting of phosphoric acid, sulfuric acid, and a mixture of phosphoric acid and sulfuric acid. (Item 7) 7. The method according to any one of items 1 to 6, characterized in that step a) is carried out for a period of 6 minutes to 14 minutes, in particular 8 minutes to 12 minutes, preferably 10 minutes. (Item 8) 8. The method according to any one of items 1 to 7, wherein step a) is carried out at a voltage of 1.45 V to 1.65 V applied to the anode. (Item 9) Step a) is 1.8A / dm 2 ~2.0A / dm 2 9. The method according to any one of items 1 to 8, characterized in that the method is carried out at a current density of 0.1 to 0.5. (Item 10) 10. The method according to any one of items 1 to 9, characterized in that step a) is carried out at a temperature of 20°C to 90°C, in particular 50°C to 80°C, preferably 70°C to 80°C. (Item 11) 11. The method according to any one of items 1 to 10, characterized in that the surface of the master or component of the surgical instrument is not treated with a passivating acid or a passivating acid-containing solution, in particular after carrying out step a). (Item 12) 12. The method according to any one of items 1 to 11, characterized in that the execution of step b) of packaging the prototype or component of the surgical instrument follows the execution of step a), and step ab) of sterilizing the prototype or component of the surgical instrument is executed between steps a) and b), or the execution of step c) of sterilizing the prototype or component of the surgical instrument follows the execution of step b). (Item 13) 13. The method according to any one of items 1 to 12, characterized in that the prototype or component of the surgical instrument is made of stainless steel, in particular a chromium-containing stainless steel, preferably a chromium-containing corrosion-resistant stainless steel, in particular a martensitic corrosion-resistant stainless steel. (Item 14) A prototype or component of a surgical instrument comprising or made of a metal or alloy, said prototype or component of said surgical instrument being produced or producible by the method according to any one of items 1 to 13, and having the following characteristics: - a master or component of a surgical instrument, having a passivation layer having a thickness of 1 nm to 10 nm coating at least a portion of the surface of said master or component of said surgical instrument.

Claims

1. 1. A method of producing a surgical instrument or a component of a surgical instrument, the surgical instrument or component of a surgical instrument comprising or consisting of a chromium-containing stainless steel, the method comprising the steps of: a) electrochemically etching the surgical instrument or a component of the surgical instrument; Step a) is performed by applying a voltage of 1.4 V to 1.7 V to the anode and / or 1.6 A / dm ２ ~2.2 A / dm ２ The method is carried out at a current density of

2. 2. The method of claim 1, wherein a grinding operation on the surface of the surgical instrument or component of the surgical instrument precedes the execution of step a).

3. 3. The method according to claim 1 or 2, characterized in that the surgical instrument or component of the surgical instrument is not treated with a blasting agent and / or is not electropolished.

4. The method according to any one of claims 1 to 3, characterized in that step a) is carried out more than once.

5. 5. The method according to claim 1, wherein step a) is carried out using an aqueous acidic electrolyte solution.

6. 6. The method of claim 5, wherein the aqueous acidic electrolyte solution comprises a mineral acid selected from the group consisting of phosphoric acid, sulfuric acid, and a mixture of phosphoric acid and sulfuric acid.

7. 7. The method according to any one of claims 1 to 6, characterized in that step a) is carried out for a period of between 6 minutes and 14 minutes.

8. 8. The method according to any one of claims 1 to 7, characterized in that step a) is carried out with a voltage of 1.45V to 1.65V applied to the anode.

9. Step a) is 1.8 A / dm ２ ~2.0 A / dm ２ 9. The method according to claim 1, wherein the method is carried out at a current density of 0.1 to 1.

0.

10. 10. The method according to any one of claims 1 to 9, characterized in that step a) is carried out at a temperature between 20°C and 90°C.

11. 11. The method according to any one of claims 1 to 10, characterized in that the surface of the surgical instrument or of a component of a surgical instrument is not treated with a passivating acid or a solution containing a passivating acid.

12. 12. The method according to any one of claims 1 to 11, characterized in that the execution of step b) of packaging the surgical instrument or a component of a surgical instrument follows the execution of step a), and the execution of step ab) of sterilizing the surgical instrument or a component of a surgical instrument is carried out between steps a) and b), or the execution of step c) of sterilizing the surgical instrument or a component of a surgical instrument follows the execution of step b).

13. A method according to any one of claims 1 to 12, characterized in that the surgical instrument or a component of the surgical instrument is made of chromium-containing corrosion-resistant stainless steel.

14. The surgical instrument or component of the surgical instrument has the following characteristics: - A method according to any one of claims 1 to 13, comprising a passivation layer having a thickness of 1 nm to 10 nm coating at least part of the surface of the surgical instrument or component of a surgical instrument.