JP2021037227A - Food processing component contacting with food material or person, and component or member for use in food handling - Google Patents

Abstract

To provide a food processing component capable of making a surface of the component possess an antibacterial (or sterilization and disinfection) effect by non-uniformly forming dimple-shaped minute recesses and ridge-line shaped protrusions around the recesses on a surface of a member, and having a washing performance improvement effect and a powder adhesion suppression effect, and a component or a member for use in food handling.SOLUTION: In this food processing component contacting with a food material or a person, and a component or a member for use in food handling, there is employed a functionality member possessing an antibacterial action on a surface by forming a large number of dimple-shaped minute recesses and ridge-line shaped protrusions around the recesses on the surface.SELECTED DRAWING: Figure 1

Description

INDUSTRIAL APPLICABILITY The present invention has an antibacterial effect or a bacterial growth inhibitory effect (antibacterial effect or bacterial growth inhibitory effect) on the surface of a member by performing a treatment of forming dimple-shaped minute concave portions on the surface and ridgeline-shaped convex portions unevenly around the concave portions. The present invention relates to parts for food processing having an effect of improving detergency (improvement of hydrophilicity) and an effect of suppressing powder adhesion, and parts or members used for handling foodstuffs (hereinafter, also simply referred to as members).

Conventionally, stainless steel that does not easily rust has been used for food processing parts, parts and members used for handling foodstuffs, for example, kitchen sinks. In addition to antibacterial properties, it is desired that oily stains can be easily removed from this stainless steel by running water from a faucet. Further, in the container used for transporting and storing the food material, there is a problem that the yield of the food material is lowered because the powder adheres and remains. However, no suitable surface treatment for stainless steel has been found. INDUSTRIAL APPLICABILITY The present invention provides food processing equipment, parts or members used for handling foodstuffs, which are most suitable for food transportation equipment, food manufacturing machines, food manufacturing factories, etc., which have an effect of improving detergency and an effect of suppressing powder adhesion in addition to antibacterial properties. Is to provide.

Since it is excellent in antifouling property and hydrophilicity, it has not only antibacterial property but also easy cleaning, and also has a feature that the amount of powdered foodstuff or the like remaining on the surface of the member is small.

For this reason, the present inventors have repeated various studies and experiments, and based on the results, the applicants of the present application have described the fine particle peening treatment (WPC treatment (registered trademark; hereinafter the same)) in Patent Document 1. ))) To form a plurality of minute recesses (micro dimples) on the surface of a member that comes into contact with the powder (hereinafter, also referred to as a powder contact member), thereby suppressing the adhesion of the powder. Proposed.

Japanese Patent No. 6416151

Here, the applicants of the present application, etc., in order to explore the possibility of applying the surface modification technology by forming dimple-shaped minute irregularities to various fields, of a member in contact with a processing target (treatment target contact member). Various approaches have been taken, such as confirming the action and effect of forming innumerable micro-concavities and convexities on the surface in various fields, but in the process, the present inventors have made new findings that have not been known so far. Obtained.

It should be noted that the effect known as the effect of forming a plurality (innumerable) of dimple-shaped minute concave portions is to suppress the adhesion of powder or adhesive and to form innumerable fine irregularities on the sliding portion. As a result, it functions as an oil reservoir to reduce sliding resistance and suppress wear, and the effect discovered this time is a completely different effect that cannot be predicted from these.

The finding is that if dimple-shaped minute recesses and ridge-shaped protrusions are unevenly formed on the surface of the member, the antibacterial (or sterilization, sterilization) effect, as well as the cleaning property improving effect, and powder The effect of suppressing body adhesion can be produced at the same time.

The present invention has been made in view of the above-mentioned circumstances, and is antibacterial (or antibacterial) (or) on the surface of a member by forming dimple-shaped minute recesses and ridge-shaped protrusions around the recesses unevenly on the surface of the member. It is an object of the present invention to provide a food processing part having an effect of improving detergency and an effect of suppressing powder adhesion, and a part or member used for handling foodstuffs, which can have a sterilization (sterilization) effect.

Therefore, the foodstuffs according to the present invention, food processing parts that come into contact with humans, and parts or members used for handling foodstuffs are
It is characterized by using a functional member having an antibacterial action on the surface by forming innumerable dimple-shaped minute recesses on the surface and innumerable ridge-shaped protrusions around the recesses.

It can be characterized by using a functional member having hydrophilicity as well as an antibacterial action in the food material or the food processing part which comes into contact with a person, and the part or member used for handling the food material according to the present invention.

A feature of the present invention is that a functional member having an antibacterial action, hydrophilicity, and a powder adhesion suppressing effect is used in a food processing part that comes into contact with a person or a food processing part, and a part or member used for handling the food. be able to.

In the foodstuffs or food processing parts that come into contact with humans, or the parts or members used for handling foodstuffs according to the present invention, functional members having any one of hydrophilicity and powder suppressing effect as antibacterial action were used. It can be characterized by that.

The foodstuffs according to the present invention, food processing parts that come into contact with humans, and parts or members used for handling foodstuffs can be characterized in that they are used in kitchens for kitchens and sinks.

The foodstuffs or food processing parts that come into contact with humans, and the parts or members used for handling foodstuffs according to the present invention can be characterized by being used for edible spoons, forks and knives.

The food material according to the present invention, the food processing part that comes into contact with a person, and the part or member used for handling the food material can be characterized by being a doorknob, a pole, or a handrail that the person touches.

The foodstuffs or food processing parts that come into contact with people, and the parts or members used for handling foodstuffs according to the present invention are conveyors for transporting processed foods, weighing equipment, especially grippers, spoons, passing pipes and storage. It can be characterized by being a tank.

In the present invention, the pitch at which the dimple-shaped minute recesses are formed can be a value corresponding to the size of the bacterium that is the target of the antibacterial action.

The present invention can be characterized in that the pitch at which the dimple-shaped minute recesses are formed is 8.0 μm or less.

The present invention can be characterized in that the pitch at which the dimple-shaped minute recesses are formed is 0.4 μm or less.

In the present invention, the pitch at which the dimple-shaped minute recesses are formed can be 0.4 to 8.0 μm.

The present invention is characterized in that dimple-shaped minute recesses on the surface and ridge-shaped protrusions around the recesses are formed non-uniformly by projecting a shot material.

The present invention can be characterized in that ceramic fine particles are used as the shot material.

The present invention can be characterized by having a residual compressive stress on the surface.

The present invention can be characterized in that oxygen entrained together with the shot material remains on the surface during the shot treatment.

According to the present invention, it is possible to give an antibacterial (or sterilization, sterilization) effect to the surface of a member by forming dimple-shaped minute recesses and ridge-shaped protrusions around the recesses unevenly on the surface of the member. It is possible to provide a food processing part having an effect of improving detergency and an effect of suppressing powder adhesion, and a part or member used for handling foodstuffs.

Each group in various base materials in which a non-uniform uneven shape composed of dimple-shaped minute recesses and ridge-shaped protrusions around the recesses is formed on the surface of the member according to the embodiment of the present invention by fine particle peening treatment. It is a list showing the presence or absence of the antibacterial effect on the untreated material, the hydrophilicity (low contact angle) corresponding to the detergency, and the effect of suppressing the adhesion of powder. Test piece (1) used for the test according to the same embodiment: It is a figure which shows the 3D image and the surface roughness of the surface of the SUS304 stainless steel untreated member. The test piece (2) used for the test according to the same embodiment is a diagram showing a 3D image and surface roughness of the surface of the SUS304 stainless steel treated member (P43 treated). The test piece (3) used for the test according to the same embodiment is a diagram showing a 3D image and surface roughness of the surface of the SUS304 stainless steel treated member (PT1 treated). It is a figure which shows an example of the measurement data (surface shape data) of the concavo-convex pitch (interval between convex portions) of the test piece (2) of the same as above. It is a figure which shows an example of the measurement data (surface shape data) of the concavo-convex pitch (interval between convex portions) of the test piece (3). It is a cross-sectional SEM image of a single micro-recess formed experimentally by one-shot of the medium used for the fine particle peening treatment according to the same embodiment. It is a concave cross section SEM image by laser processing.

Hereinafter, an embodiment according to the present invention will be described with reference to the accompanying drawings. The present invention is not limited to the embodiments described below.

As described above, the applicants of the present application contact with the processing target in order to explore the possibility of applying the surface modification technology to various fields by forming dimples (dents, substantially concave spherical surfaces) -like minute recesses. Various approaches have been taken, such as confirming the action and effect of forming innumerable minute recesses on the surface of the member (contact member to be treated) in various fields. In the process of such an approach, the present inventors, etc. Gained new findings that were previously unknown.

In addition, in this embodiment, the member is not limited to a member that comes into contact with a member to be treated in various ways including a food processing part, a part used for handling foodstuffs, or a member, and the purpose is antibacterial or the like. It can be applied to the members to be used.

Specifically, in the process of the approach, an antibacterial activity evaluation test (test piece) was performed on a member (test piece) in which dimple-shaped minute recesses were formed on the surface and ridge-shaped protrusions were unevenly formed around the recesses by fine particle peening treatment. When it was subjected to the Japanese Industrial Standards JIS Z 2801: 2010), it was found that it had a high antibacterial action (or sterilizing action, bactericidal action).
Such findings are conventionally unknown operational effects with respect to a member in which dimple-shaped minute recesses and ridge-shaped protrusions are unevenly formed around the dimple-shaped surface, and as described above, so far. It is an unpredictable effect from the findings.

The test was conducted at the Kanagawa Prefectural Institute of Industrial Technology.
As a test method, a sample (test piece) having a different surface treatment (surface texture) was subjected to an antibacterial activity evaluation test by a film adhesion method.

The test conditions are as shown below.
Test strains: Escherichia coli NBRC3972 strain inoculum concentration: 3.3 × ¹⁰ 5 CFU / mL
Bacterial solution inoculation amount: 0.4 mL
Test area: 40 x 40 mm square Covering film: Esclinica Pack L, manufactured by Sekisui Chemical Co., Ltd. Test temperature: 35 ° C
Test time: 8 hours
A microbial medium sheet for coliform bacteria (manufactured by JNC Co., Ltd.) was used for measuring the viable cell count.
The viable cell count was measured by washing the sample with 9.6 mL of sterile physiological saline and measuring the viable cell count concentration in the washed out solution.

As a result, the flat plate test piece (1) "SUS304 # 400 untreated" prototyped from the same material as the reference part spoon (1) was found to have the viable cell count concentration (CFU / mL) of Escherichia coli in 3 lots of the test piece. Was in the range of 4.0 × 10 ^{3 to} 1.7 × 10 ⁴ (the range corresponding to the “standard” of the antibacterial improvement effect in FIG. 1). In "SUS304 # 400 untreated", the surface of a stainless steel plate made of SUS304 is polished and finished with a P400 buff, and as shown in FIG. 2, the surface has a gloss close to a mirror surface and is slightly. Streaky grooves are observed. For reference, the surface has a surface roughness Ra = 0.031 μm and a surface roughness Rz = 0.364 μm. Further, although it is not a dimple-shaped minute recess, the pitch of the streaks (stripe grooves) is about 0.4 to 0.8 μm, and the depth is about 0.05 μm.
The test pieces (2) to (3), which will be described later, are obtained by subjecting the test pieces (1) to various surface treatments.

The measured values of the 3D image, the surface roughness Ra, and the surface roughness Rz in the present embodiment, including those described later, are from the actual surface property measurement data, and are shape measurement lasers manufactured by KEYENCE. Obtained using a microscope VK-X100.

Test piece (2) The antibacterial test result of "SUS304 # 400 P43" shows that the viable cell count concentration (CFU / mL) of Escherichia coli in all 3 lots is less than 1 (<1), and Escherichia coli is sterilized or sterilized. It was sterilized, and as shown in FIG. 1, it was confirmed that a clear antibacterial action could be obtained with respect to the test piece (1) of the above reference material.

The test piece (2) "SUS304 # 400 P43" is subjected to surface treatment (fine particle peening treatment or microdimple treatment) for forming dimple-shaped minute recesses on the test piece (1). In addition, for example, the first type of media (trade name "Fuji Random (Carborundum)", particle number C # 400 (maximum particle diameter 75 μm or less, particle diameter 30.0 ± 2.0 μm at a cumulative height of 50%)) SiC (Silicon Carbide)) is injected from an injection nozzle together with compressed air of about 1 / (for example, 0.3) MPa, and is projected onto the surface to be processed (the surface of the sample and the surface of the member) (hereinafter, also referred to as projection processing). ).
Next, for example, the second type of media (trade name "Fuji Random (Carborundum)", grain number C # 3000 (maximum particle size 13 μm or less, particle size 4.0 ± 0.5 μm at a cumulative height of 50%) ) (SiC (Silicon Carbide)) was projected onto the surface to be processed (projection processing) together with compressed air of about 1 / several (for example, 0.4) MPa.
The micro-concavo-convex forming process (fine particle peening process) in which the above-mentioned media having different specifications are projected in two stages is referred to as P43 here.
As shown in FIG. 3, the test piece (2) has innumerable dimple-shaped minute recesses randomly formed on the surface thereof. For reference, the surface has a surface roughness Ra = 0.252 μm and a surface roughness Rz = 3.238 μm.

Here, conventionally, in the projection process of projecting a fine particle-like medium (shot material) to form dimple-like minute recesses, the surface roughness Ra = 0.252 μm and the surface roughness Rz = 3.238 μm. It is difficult to form recesses (the uneven pitch (distance between adjacent convex portions) of the sample (2) is about 1.7 to 7.3 μm, and the depth of the concaves is about 0.2 to 1.0 μm). However, through experiments, research, etc. by the present inventors, media (shot materials) with different specifications are projected in two stages, so that even stainless steel materials have very small dimple-shaped minute recesses. Can now be randomly formed innumerably.

As shown in FIG. 1, Escherichia coli is sterilized or sterilized in the test piece (2) "SUS304 # 400 P43", and a clear antibacterial action is obtained against the test piece (1) of the above reference material. There is.

The test piece (2) "SUS304 # 400 P43" is obtained by subjecting the test piece (1) to a surface treatment (fine particle peening treatment) for forming dimple-shaped minute recesses. First type of media (trade name "Fuji Random (Carborundum)", grain number C # 400 (maximum particle diameter 75 μm or less, particle diameter 30.0 ± 2.0 μm at cumulative height 50% point) SiC (silicon carbide) (Silicon)) is injected from an injection nozzle together with compressed air of about 1 / (for example, 0.3) MPa, and a projection process (hereinafter, also referred to as projection process) is performed on the surface to be processed (surface of the sample, surface of the member). ..
Next, for example, the second type of media (trade name "Fuji Random (Carborundum)", grain number C # 3000 (maximum particle size 13 μm or less, particle size 4.0 ± 0.5 μm at a cumulative height of 50%) ) (SiC (Silicon Carbide)) was projected onto the surface to be processed (projection processing) together with compressed air of about 1 / several (for example, 0.4) MPa.
The fine particle peening process (fine particle peening process) in which the above-mentioned media having different specifications are projected in two stages is referred to as P43 here.

Here, conventionally, in the projection process of projecting a fine particle-like medium (shot material) to form dimple-like minute recesses, the uneven pitch (adjacent convex portions) of the minute concave portions (test piece (2) (P43 treatment)). It was difficult to form a range of (interval) of about 1.7 to 7.3 μm and a range of recess depth of about 0.2 to 1.0 μm), but through experiments and researches by the present inventors, etc. By performing projection processing on media (shot materials) with different specifications in two stages, it has become possible to randomly form innumerable dimple-shaped minute recesses even for stainless steel materials. ..

Test piece (3) As for the antibacterial test result of "SUS304 # 400 PT1", the viable cell count concentration (CFU / mL) of Escherichia coli was less than 1 in all 3 lots (<1). It was confirmed that Escherichia coli was sterilized or sterilized, and as shown in FIG. 1, a clear antibacterial action was obtained against the test piece (1) of the reference material.

The test piece (3) "SUS304 # 400 PT1" is obtained by subjecting the test piece (1) to a surface treatment (fine particle peening treatment) for forming dimple-shaped minute recesses. Tungsten carbide powder manufactured by Nippon Metal Co., Ltd., symbol WC-10 (particle size: 0.70 to 1.19 μm) is injected from an injection nozzle together with compressed air of about 1 / several (for example, 0.4) MPa to be coated. Projection processing was performed on the machined surface.
The micro-concavo-convex forming process (fine particle peening process) that performs such projection processing is referred to as PT1 here.
As shown in FIG. 4, the test piece (3) has innumerable dimple-shaped minute recesses randomly formed on the surface thereof. For reference, the surface has a surface roughness Ra = 0.042 μm and a surface roughness Rz = 0.689 μm.

Here, conventionally, in the projection process of projecting a fine medium (shot material) to form dimple-shaped minute recesses, the surface roughness Ra = 0.042 μm and the surface roughness Rz = 0.689 μm. Concavities (sample (3) (PT1 treatment) unevenness pitch (interval between adjacent convex parts) range of about 0.4 to 1.0 μm, concave depth range of about 0.04 to 0.17 μm) are formed. However, through experiments, research, etc. by the present inventors, by using a medium (shot material) with a large specific gravity of about tungsten carbide or more, even stainless steel material has a very small dimple shape. It has become possible to randomly form innumerable minute recesses.

Further, FIG. 5 shows surface shape data obtained by observing the uneven pitch of the minute recesses of the test piece (2) “SUS304 # 400 P43”. The uneven pitch (spacing of convex portions) range (μm) of the test piece (2) is about 1.7 to 7.3 μm, and the average uneven pitch (spacing of convex portions) is about 3.56 μm. The recess depth range is about 0.2 to 1.0 μm, and the average recess depth is about 0.51 μm.

Further, FIG. 6 shows surface shape data obtained by observing the uneven pitch of the minute recesses of the test piece (3) “SUS304 # 400 PT1”. The uneven pitch (distance between convex portions) range (μm) of the sample (3) is about 0.4 to 1.0 μm, and the average uneven pitch (interval between convex portions) is about 0.72 μm. The recess depth range is about 0.04 to 0.17 μm, and the average recess depth is about 0.10 μm.

As can be seen from FIGS. 5 and 6, the uneven surface formed by the fine particle peening treatment is completely different from the geometrical and regular uneven shape formed according to the drawing designed in advance by laser processing or the like, and has a dimple shape. It is characterized in that the minute concave portion and the ridge-shaped convex portion around the concave portion are formed unevenly in their respective shapes, pitches, and depths.

By the way, the test pieces (2) and (3) are extremely antibacterial, sterilized, and sterilized against Escherichia coli as compared with the test piece (1) in which streaky grooves (polishing grooves) are formed on the surface by polishing finish. effective.

This is where detailed analysis is awaited, but the dimple-shaped minute recesses formed by the fine particle peening process are ground or wrapped on the surface of a stainless steel member (sample) like the test piece (1). Unlike the recesses (recesses (streaks, grooves) whose bottoms are continuously extended in a streak shape) formed by, each recess in which the member surface is recessed in a dimple shape by the ejected media (shot material particles). However, it is considered that one of the reasons is that the adjacent concave portions are independently and randomly formed innumerably by being partitioned (separated and defined) by the peripheral convex portions of the ridgeline.

That is, according to the data provided by the Tokyo Metropolitan Health and Safety Research Center, the size of Escherichia coli (O157, O111, etc.) is 1.1 to 1.5 μm (horizontal size) x 2.0 to 6 It is about 0.0 μm (length), and E. coli gets stuck in the micro-concave formed by the fine particle peening process or rides on the convex part, so that the E. coli cannot move and move freely and die. Or, it can be predicted that an antibacterial effect (action) will occur due to the fact that the flagella, which grow relatively long in such a state where movement and movement are restricted, rotate and self-damage and die. ..

The size of Salmonella is 0.7 to 1.5 μm (horizontal size) x 2.0 to 5. Similar to Escherichia coli, a member having innumerable fine irregularities formed on its surface by the fine particle peening treatment according to the present embodiment, even for bacteria having a length of 0 μm and having a similar size. Is considered to have antibacterial, sterilizing, and bactericidal effects.

That is, the antibacterial member in which innumerable dimple-shaped minute recesses are formed on the surface by the fine particle peening treatment according to the present embodiment is applied to "general bacteria such as Escherichia coli and Salmonella, which are gram-negative bacteria having flagella". It is considered possible.

In addition, as general bacteria, there are also Bordetella pertussis, Mycobacterium tuberculosis, Klebs-Löyma, Shigella, Vibrio cholerae, etc. Since the size of B. coli is small and the size of B. pertussis is, for example, 0.2 μm × 0.3 to 1.0 μm, a value corresponding to the size of the bacterium that is the target of the antibacterial action in the present invention (dimple according to the present invention). The lower limit of the pitch at which the shape-like minute recesses are formed is considered to be about 0.2 μm (the pitch at which the dimple-shaped minute recesses are formed can be said to be 0.2 μm or more).

As described above, according to the present embodiment, the bottom of the recess is formed on the surface of the stainless steel member by the fine particle peening treatment instead of the recesses (streaks, grooves) extending in a streak pattern. Antibacterial, sterilizing, and bactericidal effects (or bacteria) against bacteria such as Escherichia coli by randomly forming innumerable microrecesses that are defined through the bottom and the convex part of the ridge and are independently formed. Growth inhibitory effect) can be produced.

Subsequently, a flat plate test piece was prepared using the SUS430 base material used for the kitchen sink, and various characteristics under the surface treatment conditions carried out were compared and evaluated with the base material not subjected to the fine particle peening treatment.
As a result, as shown collectively in FIG. 1, various properties such as antibacterial property, detergency (hydrophilicity), and powder adhesion suppressing effect can be significantly improved as compared with the untreated substrate.

That is, according to the present embodiment, the fine particle peening treatment (WPC treatment) forms a non-uniform uneven shape composed of dimple-shaped minute concave portions and ridge-shaped convex portions around the concave portions, thereby forming an antibacterial shape on the surface of the member. It is possible to provide a functional member capable of (or sterilizing, sterilizing) effect, and at the same time, improving detergency and suppressing powder adhesion.

Here, in the fine unevenness forming treatment (fine particle peening treatment (WPC treatment)) according to the present embodiment, the media (shot material, abrasive particles) as described above is injected by a known injection device to make contact with the processing target. This can be done by colliding with the surface of a member such as a member.

For example, a blasting device can be used as the injection device, and as an example of the blasting device, for example, "PNEUMA BLASTER" (model: SC series, SG series, etc.) manufactured by Fuji Seisakusho Co., Ltd. can be used. it can. Further, for example, those described in Japanese Patent Application Laid-Open No. 2019-25584 can be used.

More specifically, as an injection device that injects the injection particles toward the surface of the member, a known blasting device (blasting) that injects an abrasive (fine particles) together with a compressed gas (air, argon, nitrogen, etc.). Processing equipment) can be used.

The blasting device (blasting device) is a suction type blasting device that injects the abrasive by using the negative pressure generated by the injection of the compressed gas, and the abrasive that has fallen from the abrasive tank is compressed gas. A gravity-type blasting device that injects on the abrasive, introduces compressed gas into the tank into which the abrasive is charged, and feeds the abrasive flow from the abrasive tank to the compressed gas flow from the separately given compressed gas supply source. A direct pressure type blasting device that merges and injects, and a blower type blasting device that injects the above direct pressure type compressed gas flow on a gas flow generated by a blower unit are commercially available. Can be used for injecting the above-mentioned injection particles.
A water jet that injects a shot at high pressure together with a liquid such as water can also be used.

By the way, in the present embodiment, innumerable dimple-shaped minute recesses are randomly formed by the fine particle peening treatment (WPC treatment), but the present invention is not limited to this, and members such as contact members to be treated are not limited to this. By applying chemical polishing (chemical etching) to the surface of the above, a plurality (many) of minute recesses can be randomly formed. As chemical polishing (chemical etching), for example, it is assumed that acidic chemicals such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid, iron (III) chloride, and the like are prepared in an aqueous solution at an arbitrary ratio and used. In particular, when the member has a tube shape (cylindrical shape), it is difficult to form minute irregularities on the inner surface (inner peripheral surface) of the member by the fine particle peening treatment, so that the inner surface (inner surface) of the tube-shaped (cylindrical) member. The chemical etching treatment is effective when the peripheral surface) is provided with various actions, effects, characteristics, etc. according to the present invention.

Further, by applying an argon bombard treatment to the surface of a member such as a contact member to be treated, it is possible to randomly form a plurality (many) of irregularities of submicron or less on the contact surface.

The member or the like according to the present invention can be applied to, for example, a contact member to be processed, which is in contact with the object to be processed. In that case, for example, storage, storage, transportation, sliding down, sieving, agitator, cooking bowl, cooking bowl, etc. It can be applied to members used in various treatments including instruments, surgical instruments, medical instruments and the like.

Further, the member or the like according to the present invention is not limited to the contact member to be processed as described above, and is not limited to the contact member to be processed as described above, and is a hanger for a vehicle (grip portion of a strap), another handle or handle (grip), a doorknob. , Handles, toilet seats, and other members that are touched by humans and animals. For the purpose of antibacterial (or suppression of bacterial growth), etc., any member that randomly forms innumerable dimple-shaped minute recesses can be applied.

By the way, the shape of the "member or the like having various functions such as antibacterial action on the surface" according to the present embodiment is not particularly limited, and other than the member having a surface shape such as a flat shape or a curved surface shape. Even if the member itself is a wire rod, or a net-like (net-like) or mesh-like member formed by weaving a wire rod, it can be included in the member or the like according to the present embodiment.

Here, in the present invention, in order to specify the uneven surface formed by fine particle peening from the shape or structural surface, what is the geometrical and regular uneven shape formed according to a drawing pre-designed by laser processing or the like? It is completely different, and a specific method is used in which dimple-shaped minute recesses and ridge-shaped protrusions around the recesses are formed unevenly in shape, pitch, and depth.
That is, instead of using the specific method (expression) that "the surface is given an antibacterial effect by forming minute irregularities on the surface by fine particle peening", "dimple-shaped minute concaves on the surface and ridge-shaped protrusions around the concaves". A specific method (expression) of "giving an antibacterial effect to the surface by forming the part non-uniformly" is used.
However, in comparison with the prior art, it is assumed that it may be difficult to adopt the uneven surface formed by fine particle peening as a characteristic specific method (expression) that distinguishes it from others in the above specific method (expression). Will be done.

For this reason, it is assumed that there is no choice but to specify the uneven surface formed by fine particle peening by the specific method (expression) that "the surface is given an antibacterial effect by forming fine irregularities on the surface by fine particle peening". Will be done.
Therefore, it is impossible or unrealistic at the time of filing the application for the present application to specify the minute irregularities formed by the fine particle peening treatment by the shape, structure, characteristics, etc. It will be explained below that the expression "by forming" may have to be used.

In the fine particle peening process, projected particles (media) such as glass beads are made to collide with the surface to be processed at a speed of several tens to 100 m or more per second via compressed air, and are convex to the edges without significant dimensional change. Approximately spherical micron-sized micro-recesses having a portion are irregularly formed on substantially the entire surface of the machined surface, and when the media collides with each other in the fine particle peening process to form the micro-recess, the shape is crater-like. , The periphery thereof is raised to form a convex portion (see FIG. 7), and the raised convex portion is recessed by collision with other media, so that the height of the convex portion becomes irregular (FIG. 3). -See FIG. 6).

On the other hand, in mechanical processing such as laser processing and cutting processing, regular concave portions are formed, and since the processing is removal processing, no convex portion is formed (the convex portion is not raised due to the formation of the concave portion). ). For this reason, the height of the convex portion around the minute concave portion in mechanical processing such as laser processing and cutting processing matches the height of the surface (original material surface) of the work material (member to be laser processed). (See FIG. 8).

In addition, since the fine irregularities formed by the fine particle peening treatment are formed innumerably irregularly (randomly), the surface texture (shape) formed by the fine particle peening treatment scrapes the surface such as polishing or grinding treatment. It is different from the surface shape (texture) formed by the process of giving scratches (grooves such as streaks), but when measured with a surface roughness meter etc., both values are numerically similar. , It is not possible to distinguish between the two by surface roughness and the like.

However, the effect (antibacterial effect) obtained by the surface texture (shape) formed by the fine particle peening treatment is derived from the surface shape (texture) formed by the treatment of scraping and scratching the surface such as polishing and grinding. It's an unpredictable and completely different thing.
Further, from the shot peening treatment in which media of several millimeters order is collided to apply residual stress to improve the fatigue limit, it cannot be predicted that the surface subjected to the fine particle peening treatment has an antibacterial effect.

As described above, the minute irregularities formed by the fine particle peening treatment are formed innumerably irregularly (randomly), and the shapes of the minute concave portions and the convex portions around them are irregular, and the irregularities thereof are according to the present invention. Considering that it is the source of the action and effect to be exerted, the expression "formed by the fine particle peening treatment" is used as a term for specifying the surface texture (shape) formed by the fine particle peening treatment. It is not possible to specify the surface formed by the fine particle peening treatment.
As described above, there are impossible and unrealistic circumstances at the time of filing the application for the present application to specify the minute irregularities formed by the fine particle peening treatment by the shape, structure, characteristics and the like.

The present invention is not limited to the embodiments of the invention described above, and various modifications can be made without departing from the gist of the present invention.

The present invention has an antibacterial (or sterilization, sterilization) effect and improved detergency on the surface of a member by forming a non-uniform uneven shape consisting of dimple-shaped minute recesses and ridge-shaped protrusions around the recesses on the surface of the member. It can have an effect and an effect of suppressing powder adhesion, and is beneficial and usable in the food industry, which has problems of improving workability and food yield as well as hygiene.

Claims (16)

Ingredients or foods that come into contact with humans, which are characterized by using functional members that have antibacterial activity on the surface by forming innumerable dimple-shaped minute recesses on the surface and innumerable ridge-shaped protrusions around the recesses. Parts for processing, parts or parts used for handling foodstuffs. The food processing part according to claim 1, wherein a functional member having hydrophilicity as well as an antibacterial action is used, and a part or member used for handling food. The foodstuff or food processing part that comes into contact with a person, or the part or member used for handling the foodstuff, according to claim 2, wherein a functional member having an antibacterial action, hydrophilicity, and a powder adhesion suppressing effect is used. .. The foodstuff according to claim 1, the food processing parts that come into contact with humans, and the handling of foodstuffs, which are characterized by using a functional member having any one of hydrophilicity and powder suppression effect for the antibacterial action. Parts or members used for. The food material according to any one of claims 1 to 4, the food processing part that comes into contact with a person, and the part or member used for handling the food material, which is used for a kitchen or a sink. The food material according to any one of claims 1 to 4, which is used for an edible spoon, a fork or a knife, a food processing part that comes into contact with a person, or a part or member used for handling the food material. The foodstuff or food processing part that comes into contact with a person, or a part or member used for handling the foodstuff, according to any one of claims 1 to 4, which is a doorknob, a pole or a handrail that a person touches. The foodstuff or person according to any one of claims 1 to 4, wherein the processed food is a conveyor, a measuring device, particularly a gripper, a spoon, a pipe to pass through, and a tank for storage. Parts for food processing that come into contact with food, parts or parts used for handling foodstuffs. The foodstuff or person according to any one of claims 1 to 8, wherein the pitch at which the dimple-shaped minute recesses are formed is a value corresponding to the size of the bacterium to be antibacterial action. Parts for food processing that come into contact, parts or parts used for handling foodstuffs. The food processing part according to claim 9, wherein the pitch at which the dimple-shaped minute recesses are formed is 8.0 μm or less, and the part or member used for handling the food. The food processing part according to claim 9, wherein the pitch at which the dimple-shaped minute recesses are formed is 0.4 μm or less, and the part or member used for handling the food. The food processing component that comes into contact with the food material or a person according to any one of claims 1 to 8, wherein the pitch at which the dimple-shaped minute recesses are formed is 0.4 to 8.0 μm. , Parts or parts used for handling foodstuffs. The invention according to any one of claims 1 to 12, wherein dimple-shaped minute recesses on the surface and ridge-shaped protrusions around the recesses are formed non-uniformly by projecting the shot material. Food processing parts that come into contact with foodstuffs or people, parts or parts used for handling foodstuffs. The foodstuff or food processing part that comes into contact with a person, or a part or member used for handling the foodstuff, according to claim 13, wherein ceramic fine particles are used as the shot material. The food processing part according to claim 13 or 14, which has a residual compressive stress on the surface, or a food processing part that comes into contact with a person, or a part or member used for handling the food. The food material according to any one of claims 13 to 15, which is characterized in that oxygen entrained together with the shot material remains on the surface during the shot treatment, a food processing part that comes into contact with a person, a part used for handling the food material, or the like. Element.