JP6500409B2 - Antibacterial article - Google Patents

Description

  The present invention relates to antimicrobial articles.

In articles such as air conditioners, home appliances, cooking appliances, and medical devices, in order to maintain a clean environment, adhesion of bacteria and the like to the surface of the article, and the provision of an antibacterial property capable of preventing the reproduction of attached bacteria and the like Is required.
Conventionally, in order to impart antibacterial properties to various articles, for example, photocatalytic materials and silver ions are used. For example, Patent Document 1 discloses a water-repellent resin binder, a photocatalytic material, and a water-repellent resin as a material aiming to achieve both high stain resistance and high antibacterial and antiviral properties even under weak light such as indoor space. A water-repellent photocatalyst composition and a coating film thereof are disclosed, which contain copper suboxide and the photocatalyst material and the copper suboxide are complexed.
Patent Document 2 discloses a composition containing a photocatalytic powder containing apatite having photocatalytic activity as a material capable of decomposing and removing bacteria, viruses, bacteria and the like, and the photocatalytic powder has a surface It is described that when it is in the shape of a moth, the surface area functioning as a photocatalyst is expanded, and the contact efficiency with microorganisms is further improved.
Further, Patent Document 3 is an antimicrobial glass having an antimicrobial substance in the surface layer, and in the surface layer, a diffusion layer of silver ions within a depth of 30 μm from the glass surface, and a thickness of 15 μm or more in the depth direction from the glass surface. An antimicrobial glass is disclosed having a compacted layer.

An antimicrobial article using an antimicrobial substance such as a photocatalytic material or silver ion as described in Patent Documents 1 to 3 has a problem that the antimicrobial function is not maintained when the antimicrobial substance peels off from the surface and falls off .
On the other hand, Patent Document 4 has a surface roughness (Ra) of 0.2 μm or more, and a maximum roughness (Rt) of 1 μm or more and a roughness (Pc) of 5 pcs / mm or more. By fixing a silver-containing inorganic compound having a particle diameter of 1 μm or less in the micro-recesses on the surface of the plastic film, it is possible to suppress peeling and dropping of the antibacterial inorganic compound and maintain the antibacterial function for a long time Have been described.

JP 2012-210557 A JP 2012-239499 A JP, 2013-71878, A Japanese Patent Application Laid-Open No. 9-57893

However, as described in Patent Document 1 and Patent Document 2, an antimicrobial article using a photocatalytic material does not exhibit antimicrobial properties when light irradiation is not performed.
Antibacterial articles using an antibacterial substance containing silver as described in Patent Document 3 and Patent Document 4 have insufficient antibacterial properties, and further improvement of the antibacterial properties is required. In addition, in the case of an antibacterial article using an antibacterial substance containing silver, there is a concern that metal allergy may affect the human body.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an antibacterial article which can exhibit excellent antibacterial properties.

The antibacterial article according to the present invention is used for an antibacterial filter incorporated in a medical device, and has on its surface a microprojection structure provided with a microprojection group in which a plurality of microprojections are closely arranged. And a micro uneven layer made of a cured product of the resin composition,
The average d _AVG of the distance d between adjacent microprotrusions is 90 to 500 nm, and is defined by the ratio of the average H _AVG of the height H of the microprotrusions to the average d _AVG of the distance d between the microprotrusions Average aspect ratio (H _AVG / d _AVG ) of the microprotrusions is 1.0 or more and less than 3.0,
The static contact angle of water on the surface of the fine uneven layer is 30 ° or less,
According to JIS Z 2801 (2010 version), the number of viable cells after culture (the number of viable cells after culture for 48 hours) when the test bacterial solution is inoculated on the surface of the fine uneven layer and cultured for 48 hours, It is characterized in that the sterilization rate calculated by the following formula is 99.0% or more using the number of viable cells immediately after inoculation (the number of viable cells before the test).
Sterilization rate (%) = (number of viable cells before test-number of viable cells after 48 hours of culture) x 100 / number of viable cells before test
In the antimicrobial article according to the present invention, the storage elastic modulus (E ′) at 25 ° C. of the cured product of the resin composition is 200 MPa or more, and the storage elastic modulus at 25 ° C. of the cured product of the resin composition ( The ratio (tan δ (= E ′ ′ / E ′)) of the loss elastic modulus (E ′ ′) to E ′) is preferably 0.2 or more from the viewpoint of excellent antibacterial properties.

  ADVANTAGE OF THE INVENTION According to this invention, the antimicrobial article which can exhibit the outstanding antimicrobial property can be provided.

It is a sectional view showing typically an example of an antibacterial article concerning the present invention. It is a sectional view showing typically another example of the antibacterial article concerning the present invention. It is sectional drawing (FIG. 3 (a)), a perspective view (FIG. 3 (b)), and a top view (FIG. 3 (c)) which are provided to description of the multimodal microprotrusion which has multiple vertices. It is a perspective view (FIG. 4 (a)) and a top view (FIG. 4 (b)) of the convex-projections group comprised by several micro protrusion. It is a schematic cross section which shows an example of a fine concavo-convex layer. It is the schematic which shows an example of the manufacturing method of the antimicrobial article which concerns on this invention. It is an enlarged photograph which shows an example of the fine concavo-convex layer of the antibacterial article concerning the present invention which was used for explanation of the fine concavo-convex field which has irregularly arranged microprotrusion determined by atomic force microscope. It is a figure which shows the local maximum of microprotrusion in the example of the micro uneven | corrugated layer of FIG. It is a figure which shows the Delaunay figure in the example of the fine concavo-convex layer of FIG. It is a histogram of frequency distribution of distance between adjacent maximum points created from the Delaunay diagram of FIG. It is a histogram of frequency distribution of micro protrusion height in the example of the fine concavo-convex layer of FIG. It is a schematic histogram of the frequency distribution of microprotrusion heights, which serves as an explanation for low elevation area, middle elevation area, and high elevation area regarding microprojection height. It is a flowchart which shows an example of the manufacturing process of a metal mold | die. It is a schematic diagram which shows the formation process of the fine hole formed of the manufacturing process of the metal mold | die of FIG. FIG. 14 is a schematic view provided for explaining a process of forming micro holes of different depths in the manufacturing process of the mold of FIG. 13; It is the schematic of the sampling method in gas concentration analysis by a small chamber method. It is a histogram which shows an example of frequency distribution of microprotrusion height H of the antibacterial articles concerning the present invention. It is a histogram which shows another example of frequency distribution of microprotrusion height H of the antibacterial articles concerning the present invention. It is a planar view enlarged photograph which shows an example of a multimodal microprotrusion. It is a perspective view which shows an example of the shape of a microprotrusion. FIG. 21 is a plan view, a front view, and a side view of the microprotrusion shown in the example of FIG. 20. It is a perspective view which shows an example of the shape of a microprotrusion different from the microprotrusion of FIG. FIG. 23 is a plan view, a front view and a side view of the microprotrusion shown in the example of FIG. 22. It is a perspective view which shows an example of the shape of a microprotrusion different from the microprotrusion of FIG.20 and FIG.22. FIG. 25 is a front view and a side view of the microprotrusion shown in the example of FIG. 24.

Next, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.
In the present specification, the "article" is a concept including aspects such as "plate", "sheet", "film" and the like.
In addition, as used in the present specification, the shape or geometric condition and the degree thereof are specified. For example, terms such as “parallel”, “orthogonal”, “identical”, values of length and angle, etc. Without being bound by the meaning, it shall be interpreted including the extent to which the same function can be expected.
Further, in the present invention, (meth) acrylic represents each of acrylic or methacrylic, (meth) acrylate represents each of acrylate or methacrylate, and (meth) acryloyl represents each of acryloyl or methacryloyl. .
Further, in the present invention, the cured product of the resin composition refers to a cured product after or without a chemical reaction.

The antibacterial article according to the present invention has a microprojection structure provided with a microprojection group in which a plurality of microprojections are disposed in close contact with each other, and is provided with a micro uneven layer made of a cured product of a resin composition ,
The average d _AVG of the distance d between adjacent microprotrusions is 90 to 500 nm, and is defined by the ratio of the average H _AVG of the height H of the microprotrusions to the average d _AVG of the distance d between the microprotrusions Average aspect ratio (H _AVG / d _AVG ) of the microprotrusions is 1.0 or more and less than 3.0,
It is characterized in that a static contact angle of water on the surface of the fine uneven layer is 30 ° or less.

The antimicrobial article according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an example of the antibacterial article according to the present invention. The antimicrobial article 10 illustrated in FIG. 1 is provided with a fine uneven layer 2 on one side of a substrate 1. The surface of the micro-relief layer 2 is a micro-relief surface 2a having a microprojection structure provided with a microprojection group in which a plurality of microprotrusions 3 are closely disposed, and the microrelief layer 2 is a cured resin composition It consists of things.
FIG. 2 is a cross-sectional view schematically showing another example of the antibacterial article according to the present invention. The antimicrobial article 10 ′ illustrated in FIG. 2 does not have a substrate or the fine uneven layer 2 is integrated with the substrate.

Conventionally, as an article exhibiting a function by a fine surface structure, for example, a pyramidal structure as described in JP-A-2011-33392 is periodically formed at a cycle equal to or less than the wavelength of visible light. There is also an anti-reflection film on the surface of which a fine asperity pattern is formed utilizing the principle of the so-called moth eye (moth eye) structure.
On the other hand, the present inventors have found that a hydrophilic micro uneven surface having a microprojection structure having a microprojection group in which a plurality of microprojections are assembled has a remarkably high sterilization rate of attached bacteria. did. The bacteria are considered to be wet and spread on the micro uneven surface by being hydrophilic as in the case of the micro uneven surface. The size of bacteria is typically about 1 [mu] m, since the average _{d AVG} distance d between microprotrusions in finely irregular surface of the antimicrobial articles of the present invention is 90～500Nm, compared to the _{d AVG} The bacteria are big enough. Therefore, it is considered that the tips of the plurality of microprotrusions bite into the cell membranes of the bacteria that spread wetly and adhere to the micro uneven surface, and as a result, the cell membranes of the bacteria are broken and the bacteria are killed.
In the antimicrobial article according to the present invention, the average aspect ratio of the microprotrusions defined by the ratio of the average H _AVG of the height H of the microprotrusions to the average d _AVG of the distance d between the microprotrusions (H _AVG / D _AVG ) is 1.0 or more and less than 3.0. As a result, the surface area of the fine uneven surface can be sufficiently increased, and thus the hydrophilicity of the fine uneven surface is emphasized, and it is considered that bacteria easily spread and adhere to the fine uneven surface. In addition, since the average aspect ratio of the microprotrusions is not too large, so-called sticking, in which the microprotrusions are toppled or the microprotrusions adjacent to each other are less likely to occur, the deformation of the micro uneven surface is suppressed. Sex is likely to be maintained for a long time.
Furthermore, when the material constituting the antibacterial article according to the present invention generates a sterilizing gas such as formic acid or formaldehyde, it is considered that the bacteria are also killed by the sterilizing gas. In addition, since the cells attached to the antibacterial article according to the present invention are spread by wetting on the fine uneven surface, the surface area exposed to the sterilizing gas becomes large, so that it is considered that the sterilizing effect by the sterilizing gas is easily exhibited. . Furthermore, since the micro uneven surface is hydrophilic, it reacts or interacts with the moisture in the air in a general environment or with the water on the surface when touching the human body etc., and the sterilizing gas is further generated from the micro uneven surface. It is presumed that it will be easier, and it is thought that this will also improve the antimicrobial properties.

<Fine unevenness layer>
The antibacterial article according to the present invention has a microprojection structure provided with a microprojection group in which a plurality of microprojections are disposed in close contact with each other, and is provided with a micro uneven layer made of a cured product of a resin composition. .

[Microprojection structure]
The shape of the microprotrusions is a portion of the material forming the microprotrusions in a horizontal cross section when it is assumed that the microprotrusions are cut along a horizontal plane orthogonal to the depth direction of the microprotrusions from the viewpoint of exhibiting excellent antibacterial properties It is preferable to have a structure in which the cross-sectional area occupancy ratio gradually and continuously increases as it approaches from the top to the deepest part of the microprotrusions. As a specific example of the shape of such a microprotrusion, what has perpendicular | vertical cross-sectional shapes, such as triangle shape, semicircle shape, semielliptical shape, parabolic shape, a bell shape, etc. is mentioned. The plurality of microprotrusions may have the same shape or different shapes.

In the present invention, it is from the point that the scratch resistance of the antibacterial article is improved by having the fine uneven layer having a plurality of apexes as the fine protrusions (hereinafter sometimes referred to as "multimodal fine protrusions"). preferable. In addition, the microprotrusions with only one vertex may be referred to as “unimodal microprotrusions” in contrast to multimodal microprotrusions.
The multimodal microprotrusions are relatively thicker at the bottom with respect to the dimensions near the apex compared to the unimodal microprotrusions, and furthermore, the external force is dispersed and received at more vertices. It is believed that the external force applied to the apex can be reduced to make the microprotrusion less likely to be damaged. Therefore, in the present invention, mechanical strength and scratch resistance are further improved by including multimodal microprotrusions in the microprotrusions. Further, even if the microprotrusions are damaged, the area of the damaged portion can be reduced, which also reduces the local deterioration of the function exerted by the micro uneven surface such as the antibacterial property, and further causes the appearance defect. The occurrence can be reduced. Furthermore, about half of the multimodal microprotrusions occur because the highest peak height (height of the highest peak belonging to the same microprotrusions of the same height) is generated on microprotrusions with an average value H _AVG of projection height or more. First, each peak portion receives and sacrifices damage, thereby preventing wear of the body portion lower than the peaks of the microprojections and the microprojections whose height is lower than that of the multimodal microprojections. Also by this, local deterioration such as antibacterial property can be reduced, and the occurrence of appearance defects can be further reduced.
In the present invention, each convex part which forms each peak part concerning a multimodal microprotrusion and a unimodal microprotrusion is suitably called "peak".

FIG. 3 is a cross-sectional view (FIG. 3 (a)), a perspective view (FIG. 3 (b)), and a plan view (FIG. 3 (c)) for explaining the multimodal microprotrusion having a plurality of apexes. In addition, this FIG. 3 is a figure typically shown in order to make an understanding easy, and FIG. 3 (a) is a figure which takes and shows a cross section by the broken line which connects the vertex of continuous micro protrusion. In FIGS. 3B and 3C, the xy direction is the in-plane direction of the fine uneven layer, and the z direction is the height direction of the fine protrusions. In the antimicrobial article, many microprotrusions 5 have a cross-sectional area in the case where they are cut at a cross-sectional area (a plane orthogonal to the height direction (a plane parallel to the XY plane in FIG. 3) gradually from the bottom to the apex. ) Becomes smaller and one vertex is formed. On the other hand, as multimodal microprotrusions, for example, grooves g are formed in the tip portion as if a plurality of microprotrusions are joined, and the number of apexes is two (5A), the number of apexes is three. And those having four or more vertices (not shown), and the like. The shape of the monomodal microprotrusions 5 can be roughly approximated by a round shape at the top like a paraboloid of revolution or a pointed shape at the top like a cone. On the other hand, the shape of the multimodal microprotrusions 5A and 5B is roughly approximated by a shape in which a groove-like concave portion is cut in the vicinity of the top of the unimodal microprotrusion 5 and the top is divided into a plurality of peaks. The main cutting surface shapes of the multimodal microprotrusions 5A and 5B are algebraic curves Z = a ₂ X ² + a ₄ X ⁴ + · · · + a _{2n where} a plurality of maximum points are included and the vicinity of each maximum point is a convex curve. The shape is approximated by X ^{2 n} + ···.

Moreover, an example of a multimodal microprotrusion is shown in FIGS. 19-25, respectively.
FIG. 19 is an enlarged plan view photograph showing an example of multimodal microprotrusions.
FIG. 20 is a perspective view showing an example of the shape of a microprotrusion, and FIG. 21 is a plan view (FIG. 21A) and a front view (FIG. 21B) of the microprotrusion shown in the example of FIG. And a side view (FIG. 21 (c)). These FIG. 20 and FIG. 21 are contour maps. In the microprotrusions shown in FIGS. 20 and 21, three peaks having different heights are combined to form one microprotrusion, and three radial projections formed outward from about the center are formed. The microprotrusions are produced by dividing into the regions related to these three peaks by the ditch (local minimum portion). Note that FIG. 20 and FIG. 21 partially show the data based on the measurement results by the AFM and show them in detail. The unit of numerals in FIGS. 20 and 21 is nm. The X coordinate and the Y coordinate are coordinate values from a predetermined reference position.

  22 is a perspective view showing an example of the shape of a microprotrusion different from the microprotrusions of FIG. 20, and FIG. 23 is a plan view of the microprotrusion shown in the example of FIG. 22 (FIG. 23A). They are a front view (FIG.23 (b)), and a side view (FIG.23 (c)). In the microprotrusions shown in FIGS. 22 and 23, three peaks having substantially the same height are united to create one microprotrusion, and the three peaks extend outward from the approximate center of the top. It is divided by three radial grooves.

  24 is a perspective view showing an example of the shape of a microprotrusion different from the microprotrusions of FIGS. 20 and 22, and FIG. 25 is a front view of the microprotrusion shown in the example of FIG. a)) and a side view (FIG. 25 (b)). In the microprotrusions shown in FIGS. 24 and 25, they are formed as if a plurality of microprotrusions arranged side by side in a row are joined, and the aspect ratio is in this arrangement direction and in the direction orthogonal to the arrangement direction. It is made to be different. In the case of the microprotrusions of the eyebrows, the grooves between the ridges extend in the direction orthogonal to the arranging direction.

  According to the results observed in this manner, the surface roughness is observed to be rougher than the outer side of each peak on the inner side of each peak in the multimodal microprojection, and the multimodal microprojection is Thus, due to the difference in roughness between the inside and the outside of the peak, it is possible to see the difference from the multimodal microprotrusions that are caused by the resin filling failure during the shaping process. In these perspective views and the like, locations where contour lines are not represented are locations where data are not obtained for the convenience of measurement.

  The characteristic of these multimodal microprotrusions is an inherent characteristic of multimodal microprotrusions produced by microholes provided with the corresponding shape of the forming mold, as will be described later. This is a feature that can not be obtained by the multimodal microprotrusions that are generated due to the filling failure of the resin disclosed in Japanese Patent Application Laid-Open No. 0337670. That is, since the multimodal microprotrusions due to resin filling defects are originally produced by the resin being not sufficiently filled in the micropores produced as unimodal microprotrusions, the multimodal microprotrusions have The plurality of tops are extremely small, which makes it difficult to sufficiently improve the scratch resistance.

  In addition, multimodal microprotrusions due to poor filling have poor reproducibility and thus can not mass produce uniform products, whereas the multimodal microprotrusions according to this embodiment are so-called High reproducibility can be ensured by the mold. Also, as described later, while control can be performed on the height distribution of the multimodal microprotrusions, such control is difficult for multimodal microprotrusions having poor filling.

  From the viewpoint of improving the scratch resistance, the ratio of the number of multimodal microprotrusions in all the microprotrusions present on the microrelief surface is preferably 10% to 90%, and is 20% to 85%. It is more preferable to be 30% or more and 85% or less.

Further, at least a part of the microprotrusions group is a top microprotrusions, and a plurality of peripheral microprotrusions each formed adjacent to the periphery of the top microprotrusions and having a height lower than the top microprotrusions. A group of minute projections (referred to as "convex projections" in the present invention) may be configured. By having the set of microprotrusions, the mechanical strength of the microprotrusion structure is improved.
FIG. 4 shows a perspective view (FIG. 4 (a)) and a plan view (FIG. 4 (b)) of a convex projection group constituted by a plurality of minute projections. The convex-projections group 24 shown in FIG. 4 includes a top micro-protrusion 3C having a relatively high height, and a plurality of peripheral micro-protrusions 3D having a relatively low height disposed adjacent to the periphery thereof. 4 (a) and 4 (b) are schematic views for facilitating the understanding, and the xy direction is the in-plane direction of the fine uneven layer, and the z direction is a minute protrusion. It is the height direction.
In the present invention, the top micro-protrusions are relatively higher in height than the peripheral micro-protrusions, and have a height difference of 10 nm or more, and the height difference is 20 nm or more. Is preferred. The difference in height is preferably 50 nm or less from the viewpoint of suppressing the feeling of roughness on the surface of the fine uneven layer.

  The fine asperity layer is not particularly limited, but from the viewpoint of improving the mechanical strength of the fine protrusion structure, the fine protrusions arranged around the convex protrusion group are sequentially moved away from the top fine protrusions. It is preferable to arrange so that height may become low.

The ratio of the number of micro-protrusions constituting the group of convex projections in all the micro-protrusions present on the surface of the micro-relief layer is not particularly limited, but from the viewpoint of improving the mechanical strength of the micro-protrusion structure % Or more and 90% or less is preferable, 30% or more and 85% or less is more preferable, and 50% or more and 80% or less is more preferable.
The convex projections do not include microprojections that are adjacent only to the peripheral microprojections and whose height is lower than that of the top microprojections. Further, when the convex projections are formed adjacent to each other, the peripheral microprotrusions may be shared by the adjacent convex projections.
The ratio of the number of microprotrusions constituting the group of convex projections is, for example, the number of microprotrusions among the number of microprotrusions of which the presence can be confirmed by observing the surface of the micro-relief layer by SEM or the like. It can obtain | require by calculating the ratio of the number of objects of the micro protrusion which comprises these.

  The microprotrusions of the microrelief layer may be regularly or irregularly arranged. The measurement and definition of the distance between adjacent protrusions and the height of protrusions when the micro protrusions are irregularly arranged, and their design guidelines will be described with reference to FIGS. 7 to 11. FIG. 7 is an enlarged photograph showing an example of the micro-relief layer of the antibacterial article according to the present invention, which is obtained by an atomic force microscope, which is used to explain the micro-relief surface having the microprotrusions. When the microprotrusions are regularly arranged, the distance d between the microprotrusions can be defined by the repetition period P of the projections. On the other hand, as shown in the example of FIG. 7, when the microprotrusions are irregularly arranged, the distance d between the adjacent microprotrusions has a variation. In such a case, the distance d between the microprotrusions is calculated as follows.

  (1) First, the in-plane arrangement of projections (projection arrangement) using an atomic force microscope (hereinafter referred to as AFM) or a scanning electron microscope (hereinafter referred to as SEM) Plane shape) of the The data of AFM has in-plane distribution data of the height of the fine uneven layer, and the photograph of FIG. 7 shows the in-plane distribution of the height by the luminance.

  (2) Subsequently, the maximum point (hereinafter simply referred to as a maximum point) of the height of each protrusion is detected from the in-plane arrangement thus determined. The maximum point means a point where the height is larger (maximum value) than any point around the vicinity of the eyebrow. In addition, as a method of obtaining the maximum point, various methods such as a method of obtaining the maximum point by sequentially comparing the planar view shape with the enlarged photograph of the corresponding cross-sectional shape, obtaining the maximum point by image processing of the planar view enlarged photograph, The method can be applied. FIG. 8 is a view showing the maximum points of the microprotrusions in the example of the microrelief layer of FIG. 7. The points shown by black dots in FIG. 8 are the maximum points of the respective projections. Each local maximum can be detected by processing the image data of FIG. In this process, the image data is processed in advance by a low pass filter with a Gaussian characteristic of 4.5 × 4.5 pixels, thereby preventing erroneous detection of the maximum point due to noise. Further, the local maximum point was determined in units of 1 nm (= 1 pixel) by sequentially scanning a filter for maximum value detection by 8 pixels × 8 pixels.

  (3) Next, create a Delaunay diagram (Delaunary Diagram) using the detected maximum point as a mother point. Here, with the Delaunay diagram, when Voronoi division is performed with each local maximum point as a generatrix, the mother points adjacent to each other in the Voronoi region are defined as adjacent mother points, and the adjacent mother points are obtained by connecting them with line segments. It is a netlike figure consisting of a set of triangles. Each triangle is called a Delaunay triangle, and a side of each triangle (a line connecting adjacent generation points) is called a Delaunay line. FIG. 9 is a view showing a Delaunay diagram in the example of the fine uneven layer of FIG. 7; Delaunay diagrams are in a dual relationship with Voronoi diagrams. Further, Voronoi division refers to division of a plane by a net-like figure formed of a collection of closed polygons defined by vertical bisectors of line segments (Delaunay lines) connecting between adjacent mother points. A net-like figure obtained by Voronoi division is a Voronoi diagram, and each closed region is a Voronoi region.

  (4) Next, the frequency distribution of the line segment length of each Delaunay line, that is, the frequency distribution of the distance between adjacent maximum points (the distance between adjacent protrusions) is determined. FIG. 10 is a histogram of frequency distribution of distances between adjacent local maximum points created from the Delaunay diagram of FIG. In addition, as shown in 5B of FIG. 8, when a recess such as a groove is present at the top of the protrusion, or when the top is divided into a plurality of peaks, such a protrusion is obtained from the obtained frequency distribution. The data resulting from the microstructure having a recess at the top and the microstructure having a top divided into a plurality of peaks is removed, and only the data of the protrusion itself is selected to create a frequency distribution.

  Specifically, in a microstructure having a recess at the top of a protrusion, and a microstructure relating to a multimodal microprojection in which the top is divided into a plurality of peaks, a unimodal not having such a microstructure From the numerical range in the case of microprotrusions, the distance between adjacent local maxima will be significantly different. By removing the corresponding data using this feature, only the data of the projection itself is selected to detect the frequency distribution. More specifically, for example, about 5 to 20 unimodal microprotrusions adjacent to each other are selected from an enlarged photograph of a planar view of the microprotrusions (group) as shown in FIG. (A value which is 1/2 or less of the average value of the distance between adjacent local maximum points determined by sampling normally) The data of (1) is excluded and the frequency distribution is detected. In the example of FIG. 10, data with a distance between adjacent maximum points of 56 nm or less (a small mountain at the left end indicated by arrow A) is excluded. FIG. 10 shows a frequency distribution before such exclusion processing. Incidentally, such exclusion processing may be executed by the setting of the above-mentioned filter for maximum inspection.

(5) The frequency distribution of the distance d between adjacent protrusions obtained in this manner is regarded as a normal distribution to obtain an average value d _AVG and a standard deviation σ _d . In the present invention, the maximum value d _max of the distance d between adjacent protrusions is calculated as d _max = d _AVG + 2σ _d . In the example of FIG. 10, the average value d _AVG = 158 nm and the standard deviation σ _d = 38 nm. Thus, the maximum value d _{max of the} distance d between adjacent projections d is calculated to be 234 nm.

A similar approach is applied to define the height of the protrusions. In this case, the difference in relative height of each local maximum point position from the specific reference position is acquired from the local maximum points determined by the above (2), and a histogram is formed. From the frequency distribution using this histogram, the average value H _AVG of the projection heights and the standard deviation σ _H are determined. When multimodal microprotrusions are included, one microprotrusion has a plurality of apexes, so that a plurality of these data are mixed in the histogram of the projection height H for one protuberance . Therefore, in this case, the highest point among the plurality of apexes whose ridges belong to the same minute projection is adopted as the projection height of the minute projection to obtain the frequency distribution.
FIG. 11 is a histogram of the frequency distribution of height H of the microprotrusions in the example of the microrelief layer of FIG. 7. In the example of FIG. 11, the root position of the microprotrusions is taken as a reference (height 0). In the example of FIG. 11, the average value H _AVG = 178 nm and the standard deviation σ = 30 nm. As a result, in this example, the heights of the protrusions become the average value H _AVG = 178 nm.

  In addition, the reference position in measuring the height of the microprotrusions is based on the position of the projection root, that is, the valley bottom (minimum point of the height) between the adjacent microprotrusions as the reference of the height 0. However, when the height itself of the valley bottom differs depending on the location, for example, the envelope having a series of valley bottoms between the microprotrusions has a convex-concave shape with a larger period than the distance between adjacent protrusions of the microprotrusions ( For example, as shown in the example of FIG. 5, in the case where the height of the valley bottom has swells with a period larger than the distance between adjacent protrusions of the microprojections), etc. The average value of the heights of the valley bottoms measured from the surface opposite to the surface 31 is calculated in an area sufficient for the average value to converge. (2) Next, a plane having the height of the average value and parallel to the surface on the opposite side of the fine concavo-convex surface 31 of the fine concavo-convex layer 30 is considered as a reference plane. (3) Thereafter, the height of each of the microprotrusions from the reference surface is calculated, with the reference surface again having a height of 0.

In the antimicrobial article according to the present invention, the average value d _{AVG of the} distance d between adjacent protrusions determined as described above is 90 to 500 nm, and the average H _AVG of the height H of the microprotrusions, and the micro the average aspect ratio of the fine protrusions defined by the ratio between the average _{d AVG} distance d between the projections _{(H AVG / d} AVG) is less than 1.0 to 3.0. Thereby, in the antibacterial article according to the present invention, the hydrophilicity of the fine uneven surface is emphasized, bacteria spread easily and adhere easily, and further, the average value d _{AVG of the} distance d between the adjacent projections is the size of the bacteria. Because it is small enough as compared to it, it excels in the effect of killing bacteria, and therefore exhibits excellent antibacterial properties. In addition, when the average aspect ratio of the microprotrusions is in the above range, excellent antibacterial properties can be maintained for a long time. The d _AVG is preferably 300 nm or less, more preferably 200 nm or less, from the viewpoint of further improving the antimicrobial property and the abrasion resistance. Further, from the viewpoint of productivity and antibacterial property, d _AVG is preferably 100 nm or more, and more preferably 150 nm or more.

In addition, the average aspect ratio (H _AVG / d _AVG ) of the microprotrusions is preferably 1.0 or more and less than 3.0, and is preferably 1.2 or more from the viewpoint of further improving the antimicrobial property, and microroughness It is preferable that it is 2.5 or less from the point which the shape of a surface does not deform | transform more easily and abrasion resistance improves.
The aspect ratio is defined as H / W, which is the ratio of the height H of the microprotrusions divided by the diameter W (or width or thickness) at the bottom of the valley. Here, the diameter at the valley bottom corresponds to the diameter (bottom surface) of the cylinder if the shape near the valley bottom of the microprotrusions is a cylinder. If the shape of the bottom of the microprotrusions near the bottom of the microprotrusions is not a cylinder, but the size of the diameter of the bottom surface obtained by crossing the imaginary plane connecting the valley bottoms and the microprotrusions varies depending on the in-plane direction, the maximum value is the microprotrusion And the diameter of For example, when the bottom surface shape of the microprotrusions is an ellipse, the diameter is the major axis of the ridge. In addition, when the bottom shape of the microprotrusions is a polygon, the diameter is the maximum diagonal length. In the present invention, since the plurality of microprotrusions of the microprotrusion structure are closely arranged, the average value (H / W) ave of the aspect ratio H / W of each microprotrusion is the average projection height It can be considered as _H.sub.AVG / average adjacent projection interval _d.sub.AVG .

The average value H _AVG of the height H of the microprotrusions can be appropriately selected within a range that satisfies the average aspect ratio of the microprotrusions, and although not particularly limited, it is 90 nm or more Is preferably 150 nm or more. The average value H _AVG of the height H of the microprotrusions is preferably 1000 nm or less, more preferably 700 nm or less, and still more preferably 500 nm or less, from the viewpoint of improving the scratch resistance. preferable.

  The antimicrobial article according to the present invention can be produced by forming a mold for molding by repeating anodizing treatment and etching treatment, and carrying out a molding process using this mold for molding. Here, in the case of producing micro holes by anodizing treatment, as already known in JP-A-2003-43203 etc., the distance between adjacent micro holes (corresponding to the pitch when there is no distribution at a constant value) There is a proportional relationship with depth. Therefore, the aspect ratio which is the ratio of the width to the height of the root portion is kept approximately constant in the monomodal microprotrusions to be produced.

The multimodal microprotrusions formed in the antimicrobial article are preferably formed to satisfy the following conditions in order to improve the abrasion resistance.
FIG. 12 is a schematic histogram of the frequency distribution of microprotrusion heights, which serves as an explanation for the low altitude region, the middle altitude region, and the high altitude region with respect to the microprojection height. As shown in FIG. 12, the average value of the height in the frequency distribution of the height H of the microprotrusions is H _AVE , the standard deviation is σ _H, and the region of H <H _AVE -σ _H is the low elevation region of the microprotrusions. If the region of H _AVE −σ _H ≦ H ≦ H _AVE + σ _H is the middle altitude region and the region of H _AVE + σ _H <H is the high altitude region, the number of multimodal microprotrusions in each region It is preferable that the ratio of Nm to the total number Nt of multimodal microprotrusions and unimodal microprotrusions in the entire frequency distribution satisfy the following relationship (a) or (b).
(A) Nm / Nt in medium altitude region> Nm / Nt in low altitude region
(B) Nm / Nt in medium altitude region> Nm / Nt in high altitude region
By satisfying the above relationship, the abrasion resistance of the micro uneven surface of the antibacterial article can be improved.

FIG. 17 shows a histogram of an example of the frequency distribution of the microprojection height H of the antibacterial article according to the present invention. In the example shown in FIG. 17, the average value of the heights of the microprotrusions is H _AVE = 145.7 nm, and the standard deviation thereof is σ _H = 22.1 nm.
Here, in the frequency distribution of the height H of the microprotrusions, the low altitude region is H <H _AVE −σ _H = 123.6 nm, and the middle altitude region is H _AVE −σ _H = 123.6 nm ≦ H ≦ H _AVE + σ _H = 167.8 nm, and in the high altitude region, H> H _AVE + σ _H = 167.8 nm.
Since the total number Nt of microprotrusions in the entire frequency distribution is 263, among which the number Nm of multimodal microprotrusions in the middle altitude region is 23, Nm / Nt in the middle altitude region is 0 It will be .087. Since the number Nm of multimodal microprotrusions in the low altitude region is two, the Nm / Nt in the low altitude region is 0.008. Since the number Nm of multimodal microprotrusions in the high altitude region is five, Nm / Nt in the high altitude region is 0.019.
Therefore, the antimicrobial article of the example shown in FIG. 17 has the relationship of (a), (b) described above, ie,
(A) Nm / Nt = 0.008> Nm / Nt = 0.008 in the low altitude region
(B) Nm / Nt in the middle altitude region = 0.087> Nm / Nt in the high altitude region = 0.019
Satisfy.

Furthermore, in the antimicrobial article of the present invention, the frequency distribution of the height H of the microprotrusions is bimodal with two distributions, and the height at the boundary of the two distributions is hs, and the distribution in the distribution less than hs The average value of height H of the microprotrusions is m1,
Let the region of H <m1-σ1 be the low altitude region,
Let the region of m1-σ1 ≦ H ≦ m1 + σ1 be the middle altitude region,
When the area of m1 + σ1 <H <hs is a high altitude area,
The ratio of the number Nm1 of multimodal microprotrusions in each region in the distribution less than hs to the total number Nt of microprotrusions in the entire frequency distribution satisfies the following relationship (c), (d):
(C) Nm1 / Nt in the medium altitude region> Nm1 / Nt in the low altitude region
(D) Nm1 / Nt in the medium altitude region> Nm1 / Nt in the high altitude region
And, the average value of the height h of the microprotrusions in the distribution of hs or more is m2, and the standard deviation is σ2.
Let the region of hs <H <m2-σ2 be the low altitude region,
Let the region of m 2 −σ 2 ≦ H ≦ m 2 + σ 2 be the middle altitude region,
When the area of m2 + σ2 <H is a high altitude area,
The ratio of the number Nm2 of the multimodal microprotrusions in each region in the distribution of hs or more to the total number Nt of the microprotrusions in the entire frequency distribution satisfies the following relationship (e) or (f) It may be
(E) Nm2 / Nt in the medium altitude region> Nm2 / Nt in the low altitude region
(F) Nm2 / Nt in medium altitude region> Nm2 / Nt in high altitude region
By satisfying the above relationship, the abrasion resistance of the micro uneven surface of the antibacterial article can be improved.

FIG. 18 shows a histogram of an example of the frequency distribution of the microprojection height H of the antibacterial article according to the present invention. In FIG. 18, the microprojection height H and h, and the the H _AVG average projection height m, describes respectively the standard deviation sigma _H sigma. In the example shown in FIG. 18, the height distribution of microprotrusions having a distribution peak on the high side and the low side is discrete, that is, a bimodal distribution. A distribution of multimodal microprojections is formed corresponding to the peaks. In the example shown in FIG. 18, the average value of the heights of the microprotrusions in the entire frequency distribution is m = 195.7 nm, and the standard deviation is σ = 57.2 nm.
Further, in the example shown in FIG. 18, in the frequency distribution of height h of the microprotrusions, the low altitude region is h <m−σ = 138.5 nm, and the mid altitude region is m−σ = 138.5 nm ≦ h ≦ m + σ = 252.9 m, and in the high altitude region, h> m + σ = 252.9 nm.
The total number Nt of microprotrusions in the entire frequency distribution is 131. Further, since the number Nm of multimodal microprotrusions in the middle altitude region is 21, the Nm / Nt in the middle altitude region is 0.160. Since the number Nm of multimodal microprotrusions in the low altitude region is 3, Nm / Nt in the low altitude region is 0.023. Since the number Nm of multimodal microprotrusions in the high altitude region is zero, Nm / Nt in the high altitude region is zero.
Therefore, in the example shown in FIG. 18, the relationship between (a) and (b) described above, ie,
(A) Nm / Nt = 0.160 in the middle altitude region> Nm / Nt = 0.023 in the low altitude region
(B) Nm / Nt = 0.160 in the middle altitude region> Nm / Nt = 0 in the high altitude region
Satisfy.

Further, as described above, the frequency distribution of the height h of the microprotrusions shown in FIG. 18 is bimodal, that is, has two distribution peaks. When the height between the peaks is hs, the average value of the height h of the microprotrusions in the distribution less than hs (on the lower side) is m1 = 52.9 nm, and the standard deviation is σ1 = It is 24.8 nm. The boundary of each distribution is determined as hs = 100 nm by statistically processing the data of the height of the frequency distribution.
Therefore, the low altitude region of the distribution less than hs is h <m1−σ1 = 28.1 nm, the medium altitude region is m1−σ1 = 28.1 nm ≦ h ≦ m1 + σ1 = 77.7 nm, and the high altitude region is It becomes m1 + σ1 = 77.7 nm <h <hs = 100 nm.
Further, since the number Nm1 of multimodal microprotrusions in the middle altitude region is two, Nm1 / Nt in the middle altitude region is 0.015. Since the number Nm1 of multimodal microprotrusions in the low altitude region is zero, Nm1 / Nt in the low altitude region is zero. Since the number Nm1 of multimodal microprotrusions in the high altitude region is zero, Nm1 / Nt in the high altitude region is zero.
Accordingly, the antimicrobial article of the example shown in FIG. 18 has the relationship of (c) and (d) above in the distribution below hs, ie,
(C) Nm1 / Nt = 0.015> Nm1 / Nt = 0 in the low altitude region
(D) Nm1 / Nt = 0.015> Nm1 / Nt = 0 in the high altitude region
Meet the relationship.

In addition, for the microprotrusions having a distribution of hs or higher (higher height side), the average value of the height h is m2 = 209.2 nm, and the standard deviation is σ2 = 39.4 nm.
Therefore, hs = 100 nm ≦ h <m2-σ2 = 169.9 nm in the low altitude region of the distribution of hs or more, and m2−σ2 = 169.9 nm ≦ h ≦ m2 + σ2 = 248.7 nm in the medium altitude region. The altitude region is m + σ = 248.7 nm <h.
In addition, since the number Nm2 of multimodal microprotrusions in the middle altitude region is 19, the Nm2 / Nt in the middle altitude region is 0.145. Since the number Nm2 of multimodal microprotrusions in the low altitude region is three, Nm2 / Nt in the low altitude region is 0.023. Since the number Nm2 of multimodal microprotrusions in the high altitude region is zero, Nm2 / Nt in the high altitude region is zero.
Accordingly, the antimicrobial article of the example shown in FIG. 18 has the relationship of the above (e) and (f) even in the distribution of hs or more, that is,
(E) Nm2 / Nt = 0.145 in the medium altitude region> Nm2 / Nt = 0.023 in the low altitude region
(F) Nm2 / Nt = 0.145> Nm2 / Nt = 0 in high altitude region
Meet the relationship.

In the present invention, the thickness of the fine uneven layer may be appropriately adjusted. The thickness (T in FIG. 1) of the fine asperity layer 2 can exhibit various performances with the minimum thickness capable of forming the fine asperity shape on the surface of the substrate 1. However, considering the productivity in the shaping process described later, when the thickness is thin, appearance defects due to foreign matter are likely to occur, and when the thickness is thick, there is a concern about the shaping speed and curling, so 2 μm to 30 μm Is preferable, and 3 μm to 10 μm is more preferable. In addition, the thickness of a fine concavo-convex layer means the distance of the perpendicular direction to the substrate plane from the interface by the side of the substrate of a fine concavo-convex layer to the height of the top of the highest minute projection.
The antimicrobial article according to the present invention may have no base material, and the material of the fine asperity layer and the material of the base material are the same, so that the fine asperity layer and the base material may be used. May be integrated. The fine uneven layer in this case is not particularly limited because it depends on the thickness of the substrate.

  In the case where the height of the valley bottom itself between the adjacent micro protrusions 32 differs depending on the place, for example, as shown in FIG. The periodical waviness has a constant height only in one direction (for example, X direction) in a plane (XY plane in FIG. 5) parallel to the front and back surfaces of the base material and in a direction (for example, Y direction) orthogonal thereto. Alternatively, it may have undulations in two directions (X direction and Y direction) in a plane (XY plane in FIG. 5) parallel to the front and back surfaces of the base material.

  Moreover, in order to ensure good smoothness of the antibacterial article 10, the height difference (h in FIG. 5) of the uneven surface 33 which is undulated in the period D is preferably 10 μm or less. The height difference of the uneven surface formed by the uneven surface 33 can be obtained by measuring the height difference of the positions of the valley bottoms of the minute projections 32 separated by, for example, 500 nm or more. The position of the valley bottom of the microprotrusions 32 can be determined by observing the antibacterial article 10 using a TEM or SEM photograph of a vertical cross section cut in the thickness direction.

[Resin composition]
The micro uneven | corrugated layer in this invention consists of hardened | cured material of a resin composition. The resin composition is not particularly limited, contains at least a resin, and optionally contains other components such as a polymerization initiator. The resin composition also includes those containing only one kind of resin.
The resin is not particularly limited. For example, thermosetting resins such as (meth) acrylate-based, epoxy-based, polyester-based ionizing radiation curable resins, (meth) acrylate-based, urethane-based, epoxy-based, polysiloxane-based, etc. Materials such as thermoplastic resins, thermoplastic resins such as (meth) acrylates, polyesters, polycarbonates, polyethylenes, and polypropylenes, molding resins for various cured forms, and the like. In addition, ionizing radiation means electromagnetic waves or charged particles having energy capable of polymerizing and curing molecules, for example, all ultraviolet rays (UV-A, UV-B, UV-C), visible light, gamma rays , X-rays, electron beams and the like.

  Among the above resins, ionizing radiation curable resins are preferably used in view of their excellent formability of fine concavo-convex shape and mechanical strength. The ionizing radiation curable resin is a mixture of a monomer having a radical polymerizable property and / or a cationic polymerizable bond in the molecule, a polymer having a low polymerization degree, and a reactive polymer, and the polymerization initiation is Cured by the agent. In addition, you may contain a non-reactive polymer.

The antimicrobial article of the present invention is characterized in that the condensation suppressing effect is improved by the hydrophilicity of the resin composition, and as the resin composition, the static contact angle of pure water on the surface of a flat cured film is 90. It is preferable to select and use one that is less than °. From the viewpoint of improving the hydrophilicity, it is preferable that the static contact angle of pure water on the surface of a flat cured film of the cured product of the resin composition is 60 ° or less, and more preferably 50 ° or less. preferable.
When a fine uneven layer is formed using such a hydrophilic resin composition, the static contact angle of pure water on the fine uneven surface becomes smaller than that of a flat cured film surface, and becomes hydrophilic or hydrophilic Can be made more hydrophilic, and the antibacterial property of the antibacterial article can be improved.

In the present invention, the static contact angle of pure water on the surface of the flat cured film of the resin composition can be measured in the same manner as the static contact angle of pure water on the fine uneven surface described above. The flat cured film of a resin composition can be obtained by apply | coating and hardening the resin composition for fine concavo-convex layers on a transparent base material. The cured film was dried by sufficiently drying the solvent so that the static contact angle of pure water can be reproduced (for example, within 4 ° of the standard deviation), and reacted and cured as necessary. It shall be. For example, when an ionizing radiation curable resin is used, a coating film made of a resin composition for a micro uneven layer having a thickness of 5 μm is formed on a transparent substrate, and an integrated quantity of ultraviolet light is 940 mJ / cm ² The reaction is sufficiently reacted to form a cured cured film.

  The storage elastic modulus (E ') at 25 ° C of the cured product of the resin composition is 200 MPa or more, and the storage elastic modulus (E') at 25 ° C of the cured product of the resin composition is the resin composition. It is preferable that the ratio (tan δ (= E ′ ′ / E ′)) of loss elastic modulus (E ′ ′) to is 0.2 or more from the viewpoint that the antibacterial property of the antibacterial article according to the present invention is excellent. By setting the E ′ and the tan δ to the lower limit value or more, it is considered that the microprotrusions are sufficiently hard and the cell membrane of the bacteria attached to the micro uneven surface is easily broken.

In the present invention, the storage elastic modulus (E ′) and the loss elastic modulus (E ′ ′) are measured by the following method in accordance with JIS K7244.
First, the resin composition for forming a micro uneven layer is sufficiently cured by irradiating an ultraviolet ray having an energy of 2000 mJ / cm ² for 1 minute or more, and the substrate and the fine uneven shape are not provided. Thickness 1 mm, width It is a single film 5 mm long and 30 mm long.
Next, E 'and E "at 25 ° C can be determined by applying a cyclic external force of 25 g at 10 Hz in the longitudinal direction of the cured product of the resin composition at 25 ° C and measuring the dynamic viscoelasticity. For example, Rheogel E4000 manufactured by UBM can be used as a measuring device.

As said resin composition, according to the use of antibacterial articles | goods, it selects suitably so that preferable hydrophilic property and other physical properties may be obtained.
Among ionizing radiation curable resins suitably used from the point of being excellent in moldability of fine concavo-convex shape and mechanical strength, a resin composition containing (meth) acrylate which is particularly preferably used will be specifically described below. .

(1) (Meth) Acrylate Even if it is a monofunctional (meth) acrylate having one (meth) acryloyl group in one molecule, two or more (meth) acryloyl groups in one molecule It may be a multifunctional acrylate, or may be a combination of monofunctional (meth) acrylate and polyfunctional (meth) acrylate. Among them, the cured product of the resin composition is likely to satisfy the storage elastic modulus (E ') and tan δ, and in view of increasing the hardness, contains a large amount of polyfunctional (meth) acrylate compared to monofunctional (meth) acrylate It is preferable to do.

Specific examples of the multifunctional acrylate include, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene di (meth) acrylate, hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, bisphenol A di (meth) acrylate, tetrabromobisphenol A di (meth) acrylate, bisphenol S di (meth) acrylate, butanediol di (meth) acrylate, phthalic acid di (meth) acrylate, ethylene oxide modified bisphenol A di (meth) Acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tris (a) Ryloxyl) isocyanurate, dipentaerythritol hexa (meth) acrylate, urethane tri (meth) acrylate, ester tri (meth) acrylate, urethane hexa (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, etc. .
Among them, multifunctional (meth) acrylates and polyethylene glycol di (meth) acrylates having long-chain polyethylene glycol are preferred because they are excellent in the hardness of the microprojection structure, have hydrophilicity, and improve the antimicrobial properties of the antimicrobial article. It is preferable to use at least one selected.

  It is preferable that it is 40-95 mass% with respect to the total solid of the said resin composition, and, as for content of the said polyfunctional (meth) acrylate, it is more preferable that it is 50-95 mass%. In the present invention, solid content refers to all components excluding the solvent.

  Specific examples of monofunctional (meth) acrylates include, for example, methyl (meth) acrylate, hexyl (meth) acrylate, decyl (meth) acrylate, allyl (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate , Butoxy ethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycerol (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate ) Acrylate, 2-hydroxypropyl (meth) acrylate, isobonyl (meth) acrylate, isodexyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) a Lilate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, stearyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, biphenyloxyethyl acrylate, bisphenol A diglycidyl (meth) acrylate, biphenyl yloxy ethyl (meth) acrylate, ethylene oxide modified biphenyl yloxy ethyl (meth) acrylate, bisphenol A epoxy (meth) acrylate, etc. are mentioned. These monofunctional (meth) acrylic acid esters can be used alone or in combination of two or more.

  The content of monofunctional (meth) acrylate in the case of using monofunctional (meth) acrylate is preferably 1 to 30% by mass, and 3 to 15% by mass with respect to the total solid content of the resin composition. It is more preferable that

  Moreover, when using monofunctional (meth) acrylate, the ratio of the content (parts by mass) of the monofunctional (meth) acrylate to the content (parts by mass) of the polyfunctional (meth) acrylate is a cured product of the resin composition. Is preferably 0.01 or more and less than 0.5, and more preferably 0.05 or more and less than 0.3, from the viewpoint that the storage elastic modulus (E ′) and tan δ are easily satisfied and the hardness is improved. .

From the viewpoint of improving the hydrophilicity, the resin composition is preferably a polyfunctional (meth) acrylate having a hydroxyl group, a monofunctional (meth) acrylate having a hydroxyl group, a polyfunctional (meth) acrylate having a long chain polyethylene glycol and polyethylene glycol di It is preferable to contain at least one selected from (meth) acrylates.
The total content of the polyfunctional (meth) acrylate having a hydroxyl group, the monofunctional (meth) acrylate having a hydroxyl group, the polyfunctional (meth) acrylate having long-chain polyethylene glycol and the polyethylene glycol di (meth) acrylate is a hydrophilic point of view From the viewpoint of the total solid content of the resin composition, 70 to 99% by mass is preferable, and 75 to 90% by mass is more preferable.

(2) Photopolymerization Initiator In order to initiate or accelerate the curing reaction of the (meth) acrylate, a photopolymerization initiator may be appropriately selected and used as necessary. Specific examples of the photopolymerization initiator include, for example, bisacyl phosphinxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1 , 2-Diphenylethan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [4-] (Methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2-hydroxy-2-methyl-1-phenyl -Propane-1-ketone, 2,4,6-trimethyl benzoyl diphenyl phosphine oxide, phenyl bis (2,4,6- trimethyl ben Benzoyl) - phosphine oxide, phenyl (2,4,6-trimethylbenzoyl) ethyl phosphinic acid and the like. These can be used alone or in combination of two or more.

  When a photopolymerization initiator is used, the content of the photopolymerization initiator is usually 0.8 to 20% by mass and 0.9 to 10% by mass based on the total solid content of the resin composition. Is preferred.

(3) Antistatic Agent In the present invention, the resin composition preferably contains an antistatic agent. By containing the antistatic agent, it is possible to suppress the adhesion of stains on the surface of the fine uneven layer, and the stains are easily removed at the time of wiping.
The antistatic agent can be appropriately selected and used from conventionally known ones. Specific examples of the antistatic agent include, for example, quaternary ammonium salts, pyridinium salts, various cationic compounds having cationic groups such as primary to tertiary amino groups, sulfonic acid bases, sulfuric acid ester bases, phosphoric acid esters Base, anionic compound having an anionic group such as phosphonate group, amphoteric compound such as amino acid type, amino sulfate ester type, nonionic compound such as amino alcohol type, glycerin type, polyethylene glycol type etc, alkoxide of tin and titanium And such organic metal compounds and metal chelate compounds such as their acetylacetonate salts. Among them, cationic compounds are preferable, cationic compounds having a tertiary amino group are more preferable, and trialkylamines such as N, N-dioctyl-1-octaneamine are even more preferable.

  When an antistatic agent is used, the content of the antistatic agent is usually 1 to 20% by mass, and preferably 2 to 10% by mass, with respect to the total solid content of the resin composition. In the present invention, solid content refers to all components excluding the solvent.

(4) Solvent In the present invention, the resin composition may use a solvent from the viewpoint of imparting coating properties and the like. When a solvent is used, the solvent does not react with each component in the composition, and can be appropriately selected from solvents in which the components can be dissolved or dispersed. Specific examples of such solvents include, for example, hydrocarbon solvents such as benzene and hexane, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, tetrahydrofuran, 1,2-dimethoxyethane, propylene glycol monoethyl ether ( Ether solvents such as PGME), halogenated alkyl solvents such as chloroform and dichloromethane, ester solvents such as methyl acetate, ethyl acetate, butyl acetate and propylene glycol monomethyl ether acetate, amide solvents such as N, N-dimethylformamide And sulfoxide solvents such as dimethyl sulfoxide, anone solvents such as cyclohexane, and alcohol solvents such as methanol, ethanol, and propanol, but the invention is not limited thereto. Not to. Moreover, the solvent used for a resin composition may be used individually by 1 type, and the mixed solvent of 2 or more types of solvents may be sufficient.

  It is preferable that it is 20-70 mass%, and, as for the ratio of solid content with respect to resin composition whole quantity, it is more preferable that it is 30-60 mass%.

(5) Other components The resin composition for the fine uneven layer used in the present invention may further contain other components as long as the effects of the present invention are not impaired. Other components include, for example, surfactants for adjusting wettability, fluorine compounds, silicone compounds, stabilizers, antifoaming agents, anti-repelling agents, antioxidants, aggregation inhibitors, viscosity modifiers, A mold release agent etc. are mentioned.

[Physical properties of fine uneven layer]
In the present invention, the static contact angle of pure water on the surface of the fine concavo-convex layer is 30 ° or less, and from the viewpoint of improving the antimicrobial property, it is preferably 20 ° or less, preferably 10 ° or less. More preferable.
The static contact angle of pure water on the surface of the microprojection structure is not particularly limited, but is preferably 5.0 ° or more.

In the present invention, the static contact angle of pure water on the surface of the fine uneven layer is measured as follows.
First, the antibacterial article according to the present invention is horizontally pasted on a black acrylic plate with an adhesive layer, with the fine uneven surface side as the upper surface. Next, a droplet of 1.0 μL of solvent (pure water) whose contact angle is to be measured is dropped, and the static contact angle after 10 seconds of deposition is measured according to the θ / 2 method. The measuring device can be measured, for example, using a contact angle meter DM 500 manufactured by Kyowa Interface Science.

<Base material>
The antimicrobial article according to the present invention may include a substrate as a support. The substrate used in the present invention can be appropriately selected depending on the application, and may be a transparent substrate or an opaque substrate, and is not particularly limited. Examples of the material of the transparent substrate include acetyl cellulose resins such as triacetyl cellulose, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, olefin resins such as polyethylene and polymethylpentene, and (meth) acrylic resins Resins such as polyurethane resin, polyether sulfone and polycarbonate, polysulfone, polyether, polyether ketone, acrylonitrile, methacrylonitrile, cycloolefin polymer, cycloolefin copolymer, soda glass, potassium glass, alkali-free glass, lead glass Glass, ceramics such as lead zirconate titanate (PLZT), and transparent inorganic materials such as quartz and fluorite. As a material of the said opaque base material, a metal, paper, wood, these composite materials, the composite material of these and the material of the said transparent base material etc. are mentioned, for example.
When the base and the microprojection structure are integrally formed, for example, a thermoplastic resin or the above-described resin composition for forming a micro uneven layer can be used as the material of the base.
Among them, a resin is preferable as a material of the base material from the viewpoint of generating a sterilizing gas to improve the antibacterial property, and among them, an acetyl cellulose-based resin is preferable, and triacetyl cellulose is particularly preferable.
In addition, when the antimicrobial article according to the present invention is installed on a glass part, using polyester resin base material such as polyethylene terephthalate (PET) as the base material gives scattering resistance at the time of glass breakage. It is preferable from the point of

  Further, the substrate may be a sheet or a film, and it may be unrollable, or may not be bent to such an extent that it can be wound, but may be bent by applying a load, or may not be completely bent. May be Although the thickness of a base material can be suitably selected according to a use and it is not limited in particular, it is usually 10-5000 micrometers.

The composition of the substrate used in the present invention is not limited to the composition consisting of a single layer, and may have a composition in which a plurality of layers are laminated. When a plurality of layers are stacked, layers of the same composition may be stacked, or a plurality of layers having different compositions may be stacked.
When the micro uneven layer is made of a material different from that of the substrate, a primer layer for improving the adhesion between the substrate and the micro uneven layer, and thus improving the abrasion resistance (scratch resistance) is formed on the substrate It may be formed in When using a transparent base material as a base material, this primer layer has adhesiveness to the fine uneven | corrugated layer adjacent to the said transparent base material via a primer layer, and what permeate | transmits visible light is preferable. When interference unevenness occurs due to the difference in refractive index between the transparent base and the fine uneven layer, unevenness can be reduced by adjusting the refractive index of the primer layer to an intermediate value between the base and the fine uneven layer.

The total light transmittance in the visible region of the substrate used in the present invention can be appropriately adjusted depending on the application, and is not particularly limited, and a transparent substrate having a transmittance of 80% or more can also be used. A translucent or opaque substrate having a transmittance of less than 80% may also be used. The said transmittance | permeability can be measured by JISK7361-1 (The test method of the total light transmittance of a plastics-transparent material).
When the antimicrobial article according to the present invention is used as a transparent member such as a protective film, for example, it is preferable to use a transparent substrate as the substrate. Moreover, when using the antimicrobial article which concerns on this invention in the aspect to which it affixes later, it is preferable to use a transparent base material as said base material also in order to make it not prevent design property.

The sterilization rate of the antimicrobial article according to the present invention is preferably 99.0% or more, more preferably 99.5% or more, and still more preferably 99.9% or more. The sterilization rate can be measured as follows.
Using a test piece obtained by cutting the antibacterial article according to the present invention into a 5 cm square, according to JIS Z 2801 (2010 version), the micro-relief surface of each test piece may be, for example, Staphylococcus aureus, E. coli, etc. 0.4 ml of a predetermined bacterial solution containing bacteria is dropped, and it is covered with a polyethylene terephthalate film so as to be in close contact with it, and the respective test pieces are heated in a incubator at a temperature of 35 ° C., 90% relative humidity, under fluorescent lamp irradiation Incubate for 48 hours and measure the number of viable bacteria after cultivation. Also, separately from this, the number of viable bacteria after 48 hours of culture of the unprocessed sample, and the number of viable bacteria of the test piece immediately after inoculation with the test solution (the number of viable bacteria before the test) for each test piece are the same. taking measurement. The viable cell count can be measured by luminometry. Specifically, an ATP extraction reagent is added to each washout solution, and the ATP extracted from the cells is reacted with the luminescence reagent (luciferase), and a luminescence photometer The amount of light emission can be measured by the following equation to convert it to the ATP concentration and the number of viable cells. The sterilization rate can be calculated by the following equation, using the number of viable bacteria thus measured.
Sterilization rate (%) = (number of viable cells before test-number of viable cells after 48 hours of culture) x 100 / number of viable cells before test

The antimicrobial article according to the present invention is that the concentrations of formaldehyde, acetaldehyde, formic acid and acetic acid measured by gas concentration analysis by the small chamber method (JISA 1901) are as follows from the viewpoint that the antimicrobial property is further improved: preferable.
That is, the concentration of formaldehyde is preferably 90 volppb or more, more preferably 150 volppb or more, and still more preferably 200 volppb or more. The concentration of formaldehyde is not particularly limited, but is usually 1000 volppb or less.
The concentration of acetaldehyde is preferably 80 volppb or more, more preferably 150 volppb or more, and still more preferably 200 volppb or more. The concentration of acetaldehyde is not particularly limited, but is usually 1000 volppb or less.
The concentration of formic acid is preferably 150 volppb or more, more preferably 200 volppb or more, and still more preferably 400 volppb or more. The concentration of formic acid is not particularly limited, but is usually 1000 volppb or less.
The concentration of acetic acid is preferably 20 volppb or more, more preferably 30 volppb or more, and still more preferably 40 volppb or more. The concentration of acetic acid is not particularly limited, but is usually 500 volppb or less.

In the present invention, gas concentration analysis by the small chamber method (JISA 1901) is specifically performed as follows.
The antibacterial article according to the present invention cut into a size of 0.210 m × 0.243 m is used as a test body under the conditions of a temperature of 28 ° C., a relative humidity of 50% RH, and a ventilation frequency of 0.5 times / h evaluation area 1.53 m ^2, and a sample loading factor 76.5m ² / ^{m 3,} measured using a stainless steel chamber volume 20L. The sample loading rate refers to the loading rate (m ² / m ³ ) when determining the gas concentration diffused from the unit area film surface per unit volume (m ³ ), and can be obtained by the following equation.
Sample loading rate (m ² / m ³ ) = (0.210 m × 0.243 m) × 30 / 0.020 (m ³ )
Concentrations of aldehydes such as formaldehyde and acetaldehyde were determined by allowing the chamber in which the test body was placed to be aerated with high purity air under the above conditions, and generating aldehydes from the test body one day later by DNPH (2,4 -Dinitrophenylhydrazine) The cartridge is collected, eluted with acetonitrile, and taken as a value measured by high performance liquid chromatograph (HPLC).
The concentration of an organic acid such as formic acid and acetic acid was determined by passing high purity air under the above conditions and allowing the chamber in which the test body was installed to pass gas generated from the test body one day later, filled with an absorbing solution. It collects in a jar and makes it the value measured by ion chromatography (IC).
The airborne concentration (volppb) of formaldehyde, acetaldehyde and formic acid generated from the test sample can be calculated by the following equation.
Airborne concentration (volppb) = (Airborne concentration (g / m ³ ) x ((273 + sampling temperature (° C)) / 273) x 22.4) / molecular weight Note that the atmospheric concentration (g / m ³ ) is , Can be calculated by the following equation.
・ Aldehydes:
Concentration in air (g / m ³ ) = Concentration in liquid (g / mL) × elution amount (mL) / collection amount (m ³ )
・ Organic acid:
Concentration in air (g / m ³ ) = Concentration of target component in absorbing solution (g / mL) × amount of absorbing solution (mL) / amount collected (m ³ )

In addition, the antimicrobial article according to the present invention is preferably 50 volppb or more, more preferably 80 volppb or more, from the viewpoint of excellent antimicrobial properties, as the organic acid concentration measured by concentration analysis of the organic acid with a gas detection tube. preferable.
Concentration analysis of organic acid by gas detection tube has good correlation with the small chamber method and can be relied on, for example, Chie Sano, 2 others, "evaluation method of reduction measure of organic acid in display case", preservation science, Tokyo National Research Institute for Cultural Properties, 2013, No. 53, p. 33-43.
In the present invention, the concentration analysis of the organic acid by the gas detection tube is carried out in a desiccator (37.2 L) using a Kitagawa-type gas detection tube (manufactured by Komyura Chemical Industry Co., Ltd., organic acid for art museum, No. 910) The antibacterial stopping article is set so that the sample loading rate is 3.3 (m ² / m ³ ), and the suction flow rate is 0.2 L / min, and suction is performed for 60 minutes.

  The antimicrobial article according to the present invention is not particularly limited, but depending on the application, the total light transmittance in the visible region can be 80% or more. By setting the transmittance to the lower limit value or more, in the embodiment in which the antimicrobial article according to the present invention is used by sticking to another article, damage to the design of the base can be suppressed, and visibility can be improved. It can be excellent. The said transmittance | permeability can be measured by JISK7361-1 (The test method of the total light transmittance of a plastics-transparent material).

<Applications of antibacterial articles>
The antimicrobial article according to the present invention can be used for any application where the provision of antimicrobial properties is required, and is not particularly limited. Examples of applications in which the antibacterial article according to the present invention can exhibit antibacterial properties include, for example, air conditioners such as air conditioners and air purifiers; household appliances such as refrigerators, washing machines, telephones, vacuum cleaners; microwave ovens, rice cookers, etc. Equipment for cooking; medical equipment such as medical equipment; office equipment for school equipment and other electronic equipment etc. Specifically, for example, antibacterial filters built in these various equipment, and these various articles are provided Examples thereof include protective films for display screens such as electronic display units and touch panels, films for window glass, and the like. In addition, the antimicrobial article according to the present invention can be suitably used as a disposable product. In addition, since the antibacterial article according to the present invention has a high sterilization rate and is excellent in antibacterial property, it can be suitably used as a medical equipment application.

  The antimicrobial article according to the present invention is preferably sealed in the distribution stage and opened and used immediately before use. The method of sealing the antibacterial article according to the present invention is not particularly limited, but for example, a method of bagging the antibacterial article with a vacuum laminating bag etc., a protective film made of resin on the fine uneven surface of the antibacterial article, etc. The method of sealing by sheet | seat unit by making it contact | adhere etc., the method which combined these methods, etc. are mentioned.

<Method for producing antibacterial article>
The method for producing the antibacterial article according to the present invention is not particularly limited as long as the method can form the fine uneven layer. For example, a resin composition for fine asperity layer is applied on a transparent substrate to form a coating film, and the coating film of the resin composition has asperities having an asperity shape obtained by reversing the shape of a desired fine protrusion structure After forming the asperity shape of the structure-forming original plate, the resin composition is cured, and the micro-projection structure forming original plate is peeled off to form a fine asperity layer having the micro-projection structure on the surface. And the like.
The concavo-convex shape of the microprojection structure-forming original plate is a shape in which a large number of micropores are densely formed, and is a shape corresponding to the shape of a microprojection group included in the microprojection structure.
In addition, the method of shaping the asperity shape of the microprojection structure-forming master plate into the resin composition for fine asperity layer and curing the resin composition can be appropriately selected according to the type of the resin composition and the like. .

The original plate for forming a microprojection structure is not particularly limited as long as it is not deformed and worn when it is repeatedly used, and may be metal, resin, ceramic, etc. Although it is preferable, usually, metal is preferably used. It is because it is excellent in deformation resistance and abrasion resistance. In the case of metal or non-metal, hereinafter, it is referred to as a mold.
The surface having the fine concavo-convex shape of the microprojection structure-forming original plate is not particularly limited, but is preferably made of aluminum from the viewpoint of easy oxidation and easy processing by anodic oxidation.
Specifically, for example, the original plate for forming a microprojection structure is high in purity by sputtering or the like directly or through another layer on the surface of a metal base material such as stainless steel, copper, aluminum or the like. An aluminum layer is provided, and what formed fine concavo-convex shape in the aluminum layer concerned is mentioned. The surface of the base material may be ultra-mirror-polished by an electrolytic composite polishing method using a combination of an electrolytic elution action and an abrasion action by abrasives before providing the aluminum layer. The purity of aluminum is usually 99% by weight or more.
The shape of the microprojection structure-forming original plate is not particularly limited as long as it can form a desired shape, and may be, for example, a flat plate, and the roll (hollow (hollow) may be used. Although it may be cylindrical or solid cylindrical), the above-mentioned original plate for forming a microprojection structure may be referred to as a roll-shaped mold (hereinafter referred to as a "roll mold") from the viewpoint of productivity improvement. Is preferably used.
As a roll mold used in the present invention, for example, a cylindrical metal material is used as a base material, and an aluminum layer provided directly or via various intermediate layers on the circumferential side surface of the base material, As mentioned above, what the fine uneven | corrugated shape was produced by repetition of anodizing treatment and an etching process is mentioned.
As a method of forming the fine concavo-convex shape on the microprojection structure forming original plate, for example, an anodic oxidation step of forming a plurality of micro holes in the surface of the aluminum layer by an anodic oxidation method, and etching the aluminum layer And expanding the diameter of the micro holes by etching the aluminum layer at an etching rate higher than the etching rate of the first etching step; It can form by implementing repeatedly a 2nd etching process one by one. That is, as shown in FIG. 13, the base material is treated alternately by repeating the anodic oxidation steps A1, ..., AN, and the etching steps E1, ..., EN to produce a roll die.
When forming the fine concavo-convex shape, it is possible to obtain a desired shape by appropriately adjusting the purity (amount of impurities) of the aluminum layer, the crystal grain diameter, and various conditions of the anodizing treatment and / or the etching treatment. More specifically, in the anodizing treatment, the minute holes are fabricated to have the shapes corresponding to the intended depth and the shape of the minute projections, respectively, by controlling the liquid temperature, the applied voltage, the time for anodizing, etc. be able to.
Thus, in the microprojection structure-forming original plate, a large number of micropores whose pore diameters gradually decrease in the depth direction are densely manufactured. In the micro-relief layer manufactured using the micro-protrusion structure-forming master plate, the micro-relief having a micro-protrusion group whose diameter gradually decreases as it approaches the top is formed corresponding to the micro holes. That is, the cross-sectional area occupancy rate of the material portion forming the micro-concavity and convexity in the horizontal cross section when it is assumed that the micro-concave is cut in a horizontal plane orthogonal to the depth direction of the micro-concavity and convexity The fine uneven | corrugated shape which increases continuously continuously as it approaches is formed.

(Formation process of micro holes forming micro projections)
Next, a method of forming multimodal microprotrusions and forming minute holes in which the distribution of the heights of the microprotrusions is controlled will be described. As described above, the fine holes formed in the molding die (roll plate) are formed by alternately repeating the anodizing treatment and the etching treatment, but the voltage applied in the repetitive anodizing treatment is varied. Thereby, the depth of the micropores (height distribution of microprotrusions) can be controlled. Here, since the applied voltage in the anodizing treatment is in proportion to the interval (pitch) of the micro holes to be formed, the applied voltage of the anodizing treatment can be varied in repetition of the anodizing treatment and etching For example, it is possible to control the ratio by mixing fine holes having different time to dig in the depth direction.

  In addition, in the case of varying the applied voltage in the anodizing treatment as described above, a plurality of fine holes are formed on the bottom of a thick fine hole having a large diameter (diameter), and the fine holes pertaining to multimodal fine protrusions are created. It can be done. The height distribution of the multimodal microprotrusions can also be controlled by controlling the height of the thick micropores.

FIG. 14 is a schematic view showing a process of forming the fine holes formed by the manufacturing process of the mold of FIG. 13, and is a schematic view serving to explain control of the height distribution.
As described above, although the relationship between the applied voltage in the anodizing treatment and the pitch of the fine holes is a proportional relation, practically, the pitch of the fine holes varies due to the grain boundary of aluminum to be subjected to the treatment. However, in FIG. 14, it is assumed that the fine holes are produced by the regular arrangement, assuming that this variation does not exist. In Drawing 14 (a)-Drawing 14 (e), the figure on the left shows the enlarged drawing of the surface of a roll metallic mold, and the figure on the right shows aa cross section in the figure on the left.

(First step)
As shown in FIG. 14 (a), first, an anodic oxidation process A1 is performed by applying a voltage V1 to the aluminum layer on the surface of the forming mold, and then an etching process E1 is performed to make fine holes f1. Form. Here, the anodizing step A1 is for producing a trigger for anodizing treatment subsequent to the flat surface of aluminum. In this case, the etching process may be omitted as appropriate.

(Second step)
Next, after an anodic oxidation step A2 is performed by applying a voltage V2 (V2> V1) higher than the voltage V1, an etching step E2 is performed. Thereby, in the anodizing step A2, as shown in FIG. 14 (b), among the fine holes f1 formed in the previous anodizing step A1, the fine holes f1 at the intervals corresponding to the anodizing step A2 are further dug down .
In the present embodiment, in the anodizing step A2, a process of digging every other fine hole f1 formed in the previous anodizing step A1 is performed. Therefore, on the surface of the forming mold, fine holes f2 are formed widely and deeply dug down every other two, and on the surface of the roll plate, the fine holes f1 and the fine holes f2 are mixed. .

(Third step)
Subsequently, after an anodic oxidation step A3 is performed by applying a voltage V3 (V3> V2) higher than the voltage V2, an etching step E3 is performed. In this process, fine holes with different pitches are produced. Specifically, when the voltage to be applied is gradually raised from the voltage V2 to the voltage V3 and this rise in the applied voltage is performed discretely (stepwisely), the height distribution of the microprotrusions (the distribution of the depths of the micro holes) Can be discretely produced, and the elevation of the microprotrusions can be set to a normal distribution by continuously executing the increase of the applied voltage. Therefore, in this embodiment, the application time of the applied voltage in the anodizing step A3 and the processing time of the etching step are set longer than the first step and the second step described above, as shown in FIG. As such, the fine holes f1 formed in the first anodizing step A1 are dug widely and deeply so as to be two and one, and the bottom of the fine holes f3 collected in one is substantially flat. (Flat micro hole forming step). Here, substantially flat refers to a state including not only the state in which the bottom of the microhole is flat but also the state in which the bottom is curved with a large radius of curvature.

(4th step)
Subsequently, after an anodic oxidation step A4 is performed by applying a voltage V4 (V4> V3) higher than the voltage V3, an etching step E4 is performed. In this process, a minute hole is created by the pitch according to the target inter-projection distance. Also in the anodic oxidation step A4, the applied voltage is gradually raised from the voltage V3 to the voltage V4. As a result, a part of the minute holes f3 excavated in the third step is further dug up, and as a result, as shown in FIG. Form high unimodal microprojections.

(Fifth step)
Subsequently, after the anodic oxidation step A5 is performed by changing the applied voltage to the voltage V1 in the first step, the etching step E5 is performed. In this step, as shown in FIG. 14 (e), in the bottom of the fine hole f3 which is the fine hole f3 formed in the anodizing step A3 and which is not affected by the anodizing step A4 of the fourth step. And forming a plurality of micro holes to form micro holes f5 corresponding to the multimodal micro projections (multi-hole projection micro hole forming step). Here, by adjusting the magnitude of the voltage V1 to be applied, it is possible to increase or decrease the number of fine holes formed on the bottom of the fine hole f5, or to adjust the distance between the fine holes.

From the above, on the surface of the forming mold, micro holes f1, f2, f4 forming micro projections different in height, and micro holes f5 forming multimodal micro projections are formed.
Here, in this series of steps, the minute holes f1 and f2 having different depths produced in the first step and the second step are excavated in the third step to form substantially flat minute holes f3 on the bottom surface. In the fourth step, the minute holes f3 are dug-advanced to prepare the minute holes f4 associated with the unimodal microprotrusions, and in the fifth step, the bottom of the minute holes f3 is processed to form many holes. The micro hole f5 which concerns on a peak microprotrusion is produced. Here, controlling the application time, the processing time, the processing time of the etching process, etc. of the anodizing process according to the first to fourth processes, and controlling the depth of the micro holes produced in each process Thus, it is possible to control the distribution of the heights of the microprojections and the distribution of the heights of the multimodal microprojections. In the first to fifth steps described above, the number of times may be omitted, repeated, or the steps may be integrated as necessary.

  FIG. 15 is a schematic diagram for explaining a process of forming micro holes of different depths involved in the control of the height distribution of the micro protrusions in the manufacturing process of the mold of FIG.

(First step)
Here, as shown in FIG. 15A, in the first step, first, the voltage V1 is applied to the aluminum layer on the surface of the forming mold to perform the anodic oxidation step A1, and then the etching step E1 To form fine holes f1. Here, the anodizing step A1 is for producing a trigger for anodizing treatment subsequent to the flat surface of aluminum. In this case, the etching process may be omitted as appropriate.

(Second step)
Next, after an anodic oxidation step A2 is performed by applying a voltage V2 (V2> V1) higher than the voltage V1, an etching step E2 is performed. Thereby, in the anodizing step A2, as shown in FIG. 15 (b), among the fine holes f1 formed in the previous anodizing step A1, the fine holes f1 corresponding to the anodizing step A2 are Dig deeper.

  Here, when the applied voltage V2 is set to V2 = 2 × V1, in the anodic oxidation step A2, a process of digging every other fine hole f1 formed in the previous anodic oxidation step A1 is performed. Therefore, on the surface of the forming mold, fine holes f2 which are widely and deeply dug down are alternately formed, and the fine holes f1 and the fine holes 2 are mixed on the surface of the mold. It becomes a state.

(Third step)
Subsequently, a voltage V3 (V2>V3> V1) between the voltage V1 and the voltage V2 is applied to perform the anodic oxidation step A3, and then the etching step E3 is performed. In this process, fine holes with different pitches are produced. Specifically, the voltage to be applied is a voltage V3, and a specific fine hole f1 as shown in the drawing is dug widely and deeply every other fine hole f1 as shown between the fine holes f2 arranged in the longitudinal and lateral directions. Here, when the applied voltage V3 is set to V3 = (V1) ^1/2 , the application time of the applied voltage in the anodic oxidation step A3 and the processing time of the etching step are set longer than the first step described above. As shown in FIG. 15 (c), among the fine holes f1 formed in the first anodic oxidation step A1, the fine hole f1 located at the center of the smallest square surrounded by the four fine holes f2 is selected. Deeply in depth. At the same time, among the fine holes f2 formed in the second anodic oxidation step A2, part of the fine holes f2 shown in FIG. 15 (c) is further dug down to form fine holes f3.

  As a result, as shown in FIG. 15 (c), the fine holes f2 and f3 (medium), respectively, which are deeper than f1, around the fine holes f1 (which will be the holes corresponding to the lowest micro protrusions) And, a mold having a surface structure in which holes surrounded in the plane are arranged in the plane by the holes corresponding to the microprotrusions of a high height) is obtained.

  As described above, since the micro holes to be excavated differ depending on the switching of the applied voltage in a plurality of times of anodizing treatment, the depth of the micro holes can be largely different, and thereby the height of the micro projections is controlled by the intended distribution. can do.

In FIG. 6, when a photocurable resin composition is used as a resin composition for forming a micro uneven layer, and a roll mold is used as an original plate for forming a micro projection structure, a micro uneven layer is formed on a transparent substrate. An example of the method of
In the method shown in FIG. 6, in the resin supplying step, the resin composition for forming the fine asperity layer is applied to the transparent substrate 45 in the form of a belt-like film by the die 41 to form the receptive layer 46 which receives the microprojection shape. . The application method of the resin composition is not limited to the case using the die 41, and various methods can be applied. Subsequently, the transparent substrate is pressed against the peripheral side surface of the roll mold 42, which is a microprojection structure-forming original plate, by the pressure roller 43, whereby the receptive layer 46 is closely adhered to the transparent substrate. The resin composition which comprises the receiving layer 46 is fully filled in the fine uneven | corrugated shaped recessed part produced on the peripheral side of the type | mold 42. As shown in FIG. In this state, the resin composition is cured by irradiation of ultraviolet rays, thereby producing a fine uneven layer on the surface of the transparent substrate. Subsequently, the transparent base material is peeled off integrally with the hardened fine asperity layer from the roll mold 42 through the peeling roller 44. After preparing a pressure-sensitive adhesive layer or the like on this transparent base material as necessary, it is cut into a desired size to obtain the antibacterial article 10. As described above, the cured product of the resin composition on the long transparent base material 45 by the roll material is sequentially provided with the fine concavo-convex shape produced on the peripheral side surface of the roll mold 42 which is a master for micro projection structure formation. By molding, the antimicrobial article according to the present invention can be efficiently mass-produced.

  Moreover, although the above-mentioned embodiment described the case where the antimicrobial article of a film shape was produced by the forming process using a roll metal mold, this invention is not limited to this, The base material which concerns on the shape of an antimicrobial article Depending on the shape, for example, in the case of producing an antimicrobial article by processing an individual sheet using a molding die with a flat plate or a specific curved surface shape, a process relating to the molding process, an original plate for forming a microprojection structure It can change suitably according to the shape of the substrate concerning the shape of an antimicrobial article.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has the substantially same constitution as the technical idea described in the claims of the present invention, and the same effects can be exhibited by any invention. It is included in the technical scope of

Hereinafter, the present invention will be specifically described by way of examples. These descriptions do not limit the present invention.
(Preparation of original plate A for forming microprojection structure)
After polishing a rolled aluminum plate with a purity of 99.50% so that the surface has an uneven shape with a ten-point average roughness Rz of 30 nm and a period of 1 μm, application is performed in an electrolyte of 0.02 M oxalic acid aqueous solution Anodizing step A1 was performed under the conditions of a voltage of 30 V and a temperature of 20 ° C. for 160 seconds. Next, the etching step E1 was performed with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18% by mass) for 600 seconds under the condition of 35 ° C. as a first step. Next, as the second step, the anodic oxidation step A2 is carried out under the conditions of an applied voltage of 40 V and 20 ° C. for 120 seconds, and then 35 ° C. with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 mass%). The etching process E2 was performed for 500 seconds under the conditions. Subsequently, as the third step, the anodic oxidation step A3 is carried out under the conditions of an applied voltage of 30 V and 20 ° C. for 90 seconds, and then 35 ° C. in a phosphoric acid aqueous solution with a concentration of 1.8 mol / L (18 mass%). The etching step E3 was performed for 600 seconds under the conditions. Finally, a fluorine-based release agent was applied, and the excess release agent was washed to obtain an original plate A for forming a microprojection structure. The fine concavo-convex shape formed in the aluminum layer of the obtained master base for micro projection structure formation had an average interval of 90 nm, and a large number of micropores whose pore diameter gradually decreased in the depth direction were densely formed. It was a shape.

(Fabrication of master plate B for forming microprojection structure)
In the preparation of the microprojection structure-forming master plate A, the applied voltage in the anodic oxidation step A1 in the first step is 40 V, and the etching time in the etching step E1 is 700 seconds, and the anodic oxidation step A2 in the second step The applied voltage in the second step is 45 V, the etching time in the etching step E2 is 600 seconds, the applied voltage in the anodizing step A3 in the third step is 50 V, the etching time in the etching step E3 is 600 seconds, and then the fourth step As the process, after performing the anodic oxidation process A4 under the conditions of an applied voltage of 53 V and 20 ° C. for 60 seconds, the etching process under the condition of 35 ° C. for 300 seconds with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 mass%) I did E4. Subsequently, as the fifth step, the anodic oxidation step A5 is carried out under the conditions of an applied voltage of 40 V and 20 ° C. for 60 seconds, and then 35 ° C. in a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 mass%). A microprojection structure-forming master plate B was obtained in the same manner as the microprojection structure-forming master plate A except that the etching step E5 was performed for 600 seconds under the conditions. The fine concavo-convex shape formed on the aluminum layer of the obtained master structure for forming micro protrusions structure A has an average interval of 150 nm, and a large number of micro pores are formed densely with the pore diameter gradually decreasing in the depth direction It was a shape.

(Preparation of original plate C for forming microprojection structure)
In the preparation of the master B for forming a microprojection structure, the applied voltage in the anodic oxidation step A1 in the first step is 40 V, and the etching time in the etching step E1 is 900 seconds, and the anodic oxidation step A2 in the second step The applied voltage in the second step is 50 V, the etching time in the etching step E2 is 800 seconds, the applied voltage in the anodizing step A3 in the third step is 60 V, the etching time in the etching step E3 is 700 seconds, and Except that the applied voltage in the anodizing step A4 is 65 V, the etching time in the etching step E4 is 400 seconds, the applied voltage in the anodizing step A5 in the fifth step is 40 V, and the etching time in the etching step E5 is 600 seconds. In the same manner as the master B for forming a microprojection structure described above, a microprojection structure To obtain a formed plate precursor C. The fine concavo-convex shape formed on the aluminum layer of the obtained master base for micro projection structure formation had an average interval of 200 nm, and a large number of micropores whose pore diameter gradually decreased in the depth direction were densely formed. It was a shape.

(Preparation of original plate D for forming microprojection structure)
In the preparation of the master B for forming a microprojection structure, the applied voltage in the anodic oxidation step A1 in the first step is 50 V, and the etching time in the etching step E1 is 1100 seconds, and the anodic oxidation step A2 in the second step The applied voltage in the second step is 70 V, the etching time in the etching step E2 is 950 seconds, the applied voltage in the anodizing step A3 in the third step is 80 V, the etching time in the etching step E3 is 800 seconds, and Except that the applied voltage in the anodizing step A4 is 90 V, the etching time in the etching step E4 is 600 seconds, the applied voltage in the anodizing step A5 in the fifth step is 50 V, and the etching time in the etching step E5 is 600 seconds. In the same manner as the master B for forming a microprojection structure, To obtain a protrusion structure forming precursor D. The fine concavo-convex shape formed on the aluminum layer of the obtained master structure for forming micro protrusions structure A was 300 nm in average distance, and a large number of micro pores were formed densely with the pore diameter gradually decreasing in the depth direction It was a shape.

(Production of master E for forming microprojection structure)
In the preparation of the master B for forming a microprojection structure, the applied voltage in the anodic oxidation step A1 in the first step is 55 V, and the etching time in the etching step E1 is 1000 seconds, and the anodic oxidation step A2 in the second step The applied voltage in the step is 75 V, the etching time in the etching step E2 is 900 seconds, the applied voltage in the anodizing step A3 in the third step is 100 V, and the etching time in the etching step E3 is 750 seconds in the fourth step. The applied voltage in the anodizing step A4 is 120 V, the etching time in the etching step E4 is 4: 500 seconds, the applied voltage in the anodizing step A5 in the fifth step is 60 V, and the etching time in the etching step E5 is 600 seconds. Except for the above-mentioned microprojection structure-forming master B except Te to obtain a fine projection structure forming precursor E. The fine concavo-convex shape formed on the aluminum layer of the obtained master structure for forming micro protrusions structure A was 500 nm in average distance, and a large number of micro pores were formed densely with the hole diameter gradually decreasing in the depth direction It was a shape.

(Preparation of Resin Composition A for Forming Fine Asperity Layer)
The following components were dissolved in 200 parts by mass of ethyl acetate to prepare a resin composition A for fine asperity layer.
<Composition of Resin Composition A for Forming Fine Asperity Layer>
23 parts by mass of dipentaerythritol hexaacrylate (DPHA) 72 parts by mass of Alonix M-260 (polyethylene glycol diacrylate manufactured by Toagosei Co., Ltd.) 5 parts by mass of hydroxyethyl acrylate 3 parts by mass of a photoinitiator (Lucillin TPO, manufactured by BASF)

(Preparation of Resin Composition B for Forming Fine Asperity Layer)
The following components were dissolved in 200 parts by mass of ethyl acetate to prepare a resin composition B for fine asperity layer.
<Composition of Resin Composition B for Forming Fine Asperity Layer>
23 parts by mass of dipentaerythritol hexaacrylate (DPHA) 72 parts by mass of Aronix M-260 (polyethylene glycol diacrylate manufactured by Toagosei Co., Ltd.) 5 parts by mass of hydroxyethyl acrylate 3 parts by mass of a photoinitiator (Lucillin TPO, manufactured by BASF) 1 part by mass of silver dispersion (Model No. 634-20921, manufactured by Kyoto Nano Chemical Co., Ltd.)

Example 1
The resin composition A for forming fine asperity layer is applied and filled to a thickness of 20 μm so as to cover the surface of the above-mentioned original plate A for forming fine asperity structure, and 50 μm thick as a transparent base material thereon The triacetyl cellulose film (Fuji Film Co., Ltd., model number: TD80ULN) was obliquely attached, and then the attached bonded assembly was pressure-bonded with a rubber roller at a load of 10 N / cm ² . Confirm that the uniform composition was applied to the whole of the microprotrusive structure-forming original plate A, and irradiate the ultraviolet light from the transparent substrate side with the energy of 2000 mJ / cm ² to form the resin composition A for forming the micro uneven layer After being cured, a micro-relief layer having a microprojection structure was produced on the transparent substrate. Thereafter, the micro-relief layer as a cured product of the micro-relief layer forming resin composition A was peeled off from the microprojection structure forming master plate A together with the transparent base material to obtain the antibacterial article of Example 1. The microprojection structure of the obtained antimicrobial article has an average d _AVG of 90 nm between the microprotrusions, an average height H _AVG of the microprojections of 90 nm, and multimodal micropores in all the microprotrusions. The ratio of the number of projections was 80%.

Example 2
The antibacterial article of Example 2 was obtained in the same manner as in Example 1 except that the microprojection structure-forming master plate B was used in place of the microprojection structure-forming master plate A in Example 1. . The microprojection structure of the obtained antimicrobial article has an average d _AVG of the distance between the microprojections of 150 nm, an average height H _AVG of the microprojections of 180 nm, and multimodal micropores in all the microprojections. The ratio of the number of protrusions was 82%.

[Example 3]
An antimicrobial article of Example 3 was obtained in the same manner as Example 1, except that in Example 1, the microprojection structure forming original plate C was used in place of the microprojection structure forming original plate A. . The microprojection structure of the obtained antimicrobial article has an average d _AVG of the distance between microprotrusions of 200 nm, an average height H _AVG of the microprojections of 585 nm, and multimodal micropores in all the microprojections. The ratio of the number of projections was 85%.

Example 4
An antimicrobial article of Example 4 was obtained in the same manner as Example 1, except that in Example 1, the microprojection structure-forming original plate D was used in place of the microprojection structure-forming original plate A. . The microprojection structure of the obtained antimicrobial article has an average d _AVG of the distance between the microprojections of 300 nm, an average height H _AVG of the microprojections of 6600 nm, and multimodal micropores in all the microprojections. The ratio of the number of protrusions was 83%.

[Example 5]
An antimicrobial article of Example 5 was obtained in the same manner as Example 1, except that in Example 1, the microprojection structure-forming original plate E was used in place of the microprojection structure-forming original plate A. . The microprojection structure of the obtained antimicrobial article has an average d _AVG of the distance between the microprojections of 500 nm, an average height H _AVG of the microprojections of 600 nm, and multimodal micropores in all the microprojections. The ratio of the number of protrusions was 82%.

Comparative Example 1
A PET film (manufactured by Toyobo Co., Ltd., model number: A4100) was used as a comparative article of Comparative Example 1.

Comparative Example 2
Example except that in place of the master plate A for forming a microprojection structure in Example 1, a lithographic plate was used, and in place of the resin composition A for forming a microrelief layer, a resin composition B for forming a microrelief layer was used. In the same manner as in 1, a comparative article of Comparative Example 2 was obtained. The surface of the obtained comparison article had no microprojection structure and was a flat surface.

[Evaluation]
<Measurement of contact angle>
(Static contact angle of pure water on the surface of the flat cured film of the resin composition for forming fine asperity layer)
The resin compositions A and B for forming fine asperity layers were respectively coated on a PET film and cured to form a flat coating film having no fine projection structure. A droplet of 1.0 μL of pure water is dropped on a film attached to a black acrylic plate with an adhesive layer, with the surface on the coated film side as the upper surface, and the static contact angle of pure water after 10 seconds of droplet deposition is It measured. The contact angle of pure water on one side of the flat PET film used in Comparative Example 1 was also measured. The static contact angle was measured according to the θ / 2 method using a contact angle meter DM 500 manufactured by Kyowa Interface Science Co., Ltd. as a measurement apparatus. The measurement results are shown in Table 1.

(Static contact angle of pure water on micro uneven surface)
The antibacterial article obtained in each example has a fine uneven surface, the comparative article of Comparative Example 1 has one surface, and the comparative article of Comparative Example 2 has a resin composition applied and cured as the upper surface. The static contact angle of pure water was measured in the same manner as for the flat cured film surface of the above-described resin composition for forming fine asperity layer, which was attached to a plate. The measurement results are shown in Table 1.

<Measurement of storage elastic modulus (E ′) and tan δ>
The resin compositions A and B for forming fine asperity layers are sufficiently cured by irradiating each with ultraviolet light of energy of 2000 mJ / cm ² for 1 minute or more, and they do not have a microprojection structure, thickness 1 mm, width 5 mm, Test single membranes A and B each having a length of 30 mm were obtained.
Then, according to JIS K 7244, storage elastic at 25 ° C. by applying 25 g of periodic external force at 10 Hz in the longitudinal direction of the cured product of the above resin composition at 25 ° C. and measuring dynamic viscoelasticity. The modulus E ′ and the loss modulus E ′ ′ were determined, and tan δ was calculated from the results of the E ′ and E ′ ′. The measurement apparatus used Rheogel E4000 made from UBM. The measurement results are shown in Table 1.

<Gas concentration analysis by the small chamber method (JISA 1901)>
The antibacterial article obtained in Example 2 was cut into a size of 0.210 m × 0.243 m and used as a test body according to the small chamber method (JISA 1901) according to the following method, aldehydes and organic acids and ammonia The airborne concentration of was measured.
The measurement is performed under the conditions of a temperature of 28 ° C., a relative humidity of 50% RH, and a ventilation frequency of 0.5 times / h, an evaluation area of 1.53 m ² , a sample loading rate of 76.5 m ² / m ³ , and a 20 L stainless steel volume It measured about 30 test bodies using the chamber made. The sample loading rate in this example was determined by the following equation.
Sample loading rate (m ² / m ³ ) = (0.210 m × 0.243 m) × 30 / 0.020 (m ³ )

(Measurement of aldehydes)
Thirty test pieces were placed in a 20 L stainless steel chamber, and high purity air was bubbled under the above conditions, and aldehydes generated from the sample one day later were captured on a DNPH (2,4-dinitrophenylhydrazine) cartridge. Gathered. The DNPH cartridge was eluted with acetonitrile, and the concentration of aldehydes was measured by high performance liquid chromatography (HPLC). A schematic diagram of the sampling method is shown in FIG.

(Measurement of organic acid, ammonia)
Thirty test pieces were placed in a 20 L stainless steel chamber, high purity air was vented under the above conditions, and gas generated from a sample one day later was collected on an impinger filled with an absorbing solution. The concentrations of the organic acid and ammonia collected in the absorbing solution after sampling were measured by an ion chromatograph (IC). A schematic diagram of the sampling method is shown in FIG.

(Analytical value calculation method)
The air concentration (volppb) of the formaldehyde, acetaldehyde, formic acid, acetic acid and ammonia measured above was calculated according to the following equation.
Airborne concentration (volppb) = (Airborne concentration (g / m ³ ) x ((273 + sampling temperature (° C)) / 273) x 22.4) / molecular weight Note that the atmospheric concentration (g / m ³ ) is , Calculated by the following equation.
・ Aldehydes:
Concentration in air (g / m ³ ) = Concentration in liquid (g / mL) × elution amount (mL) / collection amount (m ³ )
Organic acids, ammonia:
Concentration in air (g / m ³ ) = Concentration of target component in absorbing solution (g / mL) × amount of absorbing solution (mL) / amount collected (m ³ )
A standard was used to determine the airborne concentration of each component. The lower limit of quantification was 1.1 volppb of formaldehyde, 0.71 volppb of acetaldehyde, 6 volppb of formic acid, 5 volppb of acetic acid, and 14 volppb of ammonia.
Moreover, IC measured at the detected formate ion (HCOO ^-) formic acid, acetic acid ion _(CH 3 COO ^-) was converted acetic acid, ammonium ions ^{(NH 4+)} in ammonia was calculated.
The atmospheric concentration of each gas when using the antibacterial article obtained in Example 2 as a test sample is 285 volppb of formaldehyde, 240 volppb of acetaldehyde, 450 volppb of formic acid, 50 volppb of acetic acid, ammonia Was <14 (less than the lower limit of quantification) volppb.

<Concentration analysis of organic acid by gas detector tube>
The concentrations of organic acids in the antimicrobial articles obtained in the examples and the comparative examples were measured by the following method which can be measured more easily than the small chamber method. It should be noted that the method has good correlation with the small chamber method and can be relied upon, for example, Chie Sano, 2 others, "evaluation method of reduction measure of organic acid in display case", Conservation Science, Tokyo National Research Institute for Cultural Properties , 2013, No. 53, p. 33-43.
In concentration analysis of organic acid by gas detection tube, sample load factor in desiccator (37.2 L) using Kitagawa type gas detection tube (manufactured by Komei Chemical Industry Co., Ltd., organic acid for art museum, No. 910) The antibacterial article was set to 3.3 (m ² / m ³ ), and the organic acid concentration was measured. The suction flow rate was 0.2 L / min for 60 minutes, and the measurement value was 10 ppb or more. The measurement results are shown in Table 1.

<Antimicrobial evaluation>
The antimicrobial article obtained in each example and the comparative article obtained in each comparative example were cut into 5 cm square pieces to obtain test pieces. Based on JIS Z 2801 (2010 edition), yellow on the fine uneven surface of each test piece of each example, on one side in Comparative Example 1 and on the side on which the resin composition is applied and cured in Comparative Example 2 0.4 ml of a predetermined bacterial solution containing staphylococci was dropped, and the top was covered with a polyethylene terephthalate film so as to be in close contact. The respective test pieces were cultured in a culture vessel for 48 hours under fluorescent lamp irradiation at a temperature of 35 ° C. and a relative humidity of 90%, and the number of viable bacteria after culture was measured. Furthermore, for each article, the number of viable bacteria (number of viable bacteria before the test) of the test piece immediately after inoculation of the test solution was also measured. The viable cell count was measured by a luminescence measurement method. Specifically, an ATP extraction reagent is added to each washout solution, the ATP extracted from the cells is reacted with a luminescent reagent (luciferase), and the luminescence amount is measured by a luminescence photometer to determine the ATP concentration and the number of viable cells. Converted to The antimicrobial activity value calculated by the following formula from each measured value is shown in Table 1.
Antibacterial activity value = log (the number of viable bacteria after culture of the unprocessed sample) -log (the number of viable bacteria after culture of the antimicrobial article or the comparative article)
The viable cell count of the unprocessed sample was taken as the viable cell count after culture in the comparative article of Comparative Example 1 (Toyobo Co., Ltd. product, PET film of A4100).
If the logarithm of the antibacterial activity value is 2.0 or more, it is judged that the antibacterial effect is present.
Moreover, the sterilization rate of S. aureus was calculated by the following formula. The calculation results are shown in Table 1.
Sterilization rate (%) = (previous number of viable bacteria-number of viable bacteria after 48 hours culture) × 100 / number of viable cells before trial Furthermore, in the same manner as above, E. coli is used instead of S. aureus, and the antibacterial activity value and The sterilization rate was determined. The results are shown in Table 1.

<Abrasion resistance evaluation>
The abrasion resistance of each article was evaluated by performing steel wool resistance evaluation on the antibacterial article obtained in each example and the comparative article obtained in each comparative example.
That is, first, steel wool # 0000 (made by Bonstar pound) is attached to a steel wool resistance evaluation jig having a tip diameter of φ 11.3 mm, and then, in the antibacterial article of each example, a micro uneven surface, Place the sample on the glass plate so that the surface on which the resin composition is applied and cured on one side in the comparative article of Comparative Example 1 and in the comparative article of Comparative Example 2 is careful not to allow air to enter. While doing the tape fastening of the four sides. Using the above-mentioned steel wool resistance jig adjusted so that the weight applied to the above-mentioned tip diameter will be 100 g, a sample is made to slide in the transverse direction so as to reciprocate the same portion 10 times at a scanning speed of 20 to 30 mm / sec. I rubbed the surface. A black tape was attached to the side opposite to the sample surface evaluated, and the number of scratches scratched on the sample surface was observed and counted using a three-wavelength tube, and the scratch resistance of the article was evaluated by the following evaluation criteria.
(Evaluation criteria)
A: no scratch B: one or two scratches C: three to nine scratches D: ten or more scratches

(Summary of results)
The antimicrobial articles obtained in Examples 1 to 5 have an average d _AVG of 90 to 500 nm of the distance d between the microprotrusions, and an average aspect ratio (H _AVG / d _AVG ) of 1.0 to less than 3.0. And the static contact angle of water on the surface of the fine uneven layer is 30 ° or less, so the sterilization rate is over 99.9%, the antibacterial activity value is also high, and the antibacterial activity is high. It was excellent in sex. In addition, the antimicrobial articles obtained in Examples 1 to 5 are excellent in abrasion resistance, and can be preferably used in applications in which fingers and the like of a protective film of a display screen and the like can come into contact. Among them, it is considered that the antibacterial articles obtained in Examples 1 and 2 were excellent in the scratch resistance due to the shape of the microprojection structure, and the average d _AVG of the distance between the microprojections and the microprojections It is assumed that the average H _AVG and average aspect ratio (H _AVG / d _AVG ) of the height of all of the antibacterial articles obtained in Examples 1 and 2 were relatively small.
On the other hand, since the comparative articles obtained in Comparative Examples 1 and 2 did not have the microprojection structure and were flat on the surface, they were inferior in antibacterial properties. In the evaluation of the antibacterial property of the comparative article obtained in Comparative Example 1, bacteria were grown after 48 hours of culture, and many colonies consisting of bacteria were easily visually observed on the entire surface of the test piece.

DESCRIPTION OF SYMBOLS 1 base material 2 fine uneven | corrugated layer 2a fine uneven | corrugated surface 3 micro protrusion 3C top micro protrusion 3D peripheral fine protrusion 5, 5A, 5B minute protrusion 10, 10 'antimicrobial article 24 convex-convex group 30 fine uneven layer 31 fine uneven surface 32 Micro-protrusion 33 Uneven surface 41 due to waviness Die 42 Roll mold (original plate)
43 Pressure roller 44 Peeling roller 45 Transparent substrate 46 Receiving layer g Groove

Claims (2)

A microprojection structure having microprojections formed by closely arranging a plurality of microprojections on the surface, and a micro uneven layer formed of a cured product of the resin composition,
The average d _AVG of the distance d between adjacent microprotrusions is 90 to 500 nm, and is defined by the ratio of the average H _AVG of the height H of the microprotrusions to the average d _AVG of the distance d between the microprotrusions Average aspect ratio (H _AVG / d _AVG ) of the microprotrusions is 1.0 or more and less than 3.0,
The static contact angle of water on the surface of the fine uneven layer is 30 ° or less,
According to JIS Z 2801 (2010 version), the number of viable cells after culture (the number of viable cells after culture for 48 hours) when the test bacterial solution is inoculated on the surface of the fine uneven layer and cultured for 48 hours, The antimicrobial article used for the antimicrobial filter incorporated in a medical device whose sterilization rate computed by the following formula is 99.0% or more using the number of viable cells immediately after inoculation (the number of viable cells before the test).
Sterilization rate (%) = (number of viable cells before test-number of viable cells after 48 hours of culture) x 100 / number of viable cells before test The storage elastic modulus (E ') at 25 ° C. of the cured product of the resin composition is 200 MPa or more, and the loss elastic modulus (E) relative to the storage elastic modulus (E') at 25 ° C. of the cured product of the resin composition The antimicrobial article according to claim 1 , wherein the ratio "tan δ (= E" / E ')) is 0.2 or more.