JP5496821B2 - Copper alloy-attached antibacterial paper and method for producing the same - Google Patents

Description

  The present invention relates to an antibacterial paper in which a copper alloy composition is deposited discontinuously on at least one main surface of a sheet-like paper by electron beam heating vapor deposition and a method for producing the same.

The so-called metal atom-attached antibacterial paper, in which metal atoms having antibacterial effect are attached to the surface of the paper product, is highly demanded in the field of medical care and nursing care or in general households, and the metal atom is attached to the surface of the paper product As the deposition method, dry process methods such as vacuum deposition, ion plating, and sputtering are frequently used.
As a metal atom to be attached, an atom of at least one metal selected from copper, silver, copper, zinc, and tin is mainly used. In particular, silver and copper are common and exhibit high antibacterial properties. Used as metal.
Recently, the demand for antibacterial paper, such as medical records and memo paper, has been increasing as a countermeasure against infectious diseases, particularly in the field of medical care and nursing care. In addition to antibacterial properties, it is easy to write with writing instruments such as ballpoint pens as medical recording media. There is a demand for the ease of erasing written characters (printability) and the visibility of written characters (readability).
Further, from the viewpoint of production cost, there is an increasing demand for metal atom-attached antibacterial paper using a metal or metal alloy which is less expensive than silver which is generally used frequently and hardly discolors during storage.

Patent Document 1 discloses that Ag-Cu that exhibits an excellent antibacterial and antifungal action when it exhibits an amorphous phase with a composition of Ag 20 to 60 atomic%, Cu 20 to 60 atomic%, and Sn 20 to 60 atomic%. -Sn-based alloys and methods of using the same are disclosed.
In Patent Document 2, 1 × 10 ¹⁴ to 1 × 10 ¹⁷ atoms / cm ^{2 is} formed on at least one main surface of sheet-like paper, which exhibits excellent antibacterial properties suitable for hospital charts and the like.
The antibacterial paper in which the pH of acid basicity of the antibacterial paper is adjusted to the range of 6 to 9 is disclosed, and the metal atom used is selected from silver, copper, zinc and tin At least one metal atom.
In Patent Document 3, an antibacterial laminate having at least one of antibacterial and antifungal properties, the antibacterial laminate includes a base material layer 4 including a polymer film or paper, antibacterial and antifungal at least. It comprises at least an antibacterial layer 2 on which a metal having one of them is deposited and a coating layer 1 for coating the antibacterial layer 2, and the antibacterial layer 2 is interposed between the base material layer 4 and the coating layer 1. An antibacterial laminate is disclosed wherein the coating layer 1 is formed and is a substantially nonporous polymer coating.

Patent Document 1: Japanese Patent Laid-Open No. 09-111378 Patent Document 2: Japanese Patent Laid-Open No. 11-179870 Patent Document 3: International Publication WO 2007/132912

The conventional antibacterial paper or antibacterial laminate mainly composed of silver or silver alloy disclosed in these patent documents has sufficient antibacterial properties, but has a high production cost, and in particular, sufficient printability and readability. I couldn't say that.
The present invention improves these disadvantages, has a low production cost, has excellent printability and easy readability, contains 70 to 90% by mass or more of Cu, Ag, Al, Cr, Fe, Mg, Ni Copper alloy antibacterial in which a copper alloy composition containing 10 to 30% by mass of one or more elements selected from the group consisting of Si, Sn, Ti, Zn, and Zr is non-continuously adhered on a sheet-like paper surface Paper and a method for producing the same are provided.

In order to improve the printability and readability of the metal atom-attached antibacterial paper to which metal atoms are attached, the present inventors have added an amount of metal atoms in a range that does not impair the antibacterial property to a sheet-like paper surface as a base. It has been found that it is effective to form a non-dense film that is not continuous by depositing it by electron beam heating vapor deposition.
With conventional metal atom-attached antibacterial paper, a metal film composed of metal atoms is continuously and densely formed on a sheet-like paper surface as a base, and its surface is slippery and can be printed with a writing instrument such as a ballpoint pen. In addition, the light is reflected and the printing is difficult to see.
Therefore, the printability is improved and the readability is improved by partially discontinuously exposing the sheet-like surface of the sheet as long as the antibacterial properties are not impaired.
In addition, it is preferable to use inexpensive copper as a substitute for expensive silver as a metal atom to be attached, but copper is highly discolored due to aging. By using a copper alloy composition of copper and another suitable metal, discoloration due to aging can be prevented.

That is, the antibacterial paper of the present invention contains 70 to 90% by mass of Cu on at least one main surface of the sheet-like paper, and Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn , Non-consecutive non-dense formed by depositing 30 to 94 mg / m ^{2 of} a copper alloy composition containing 10 to 30% by mass of one or more elements selected from the group consisting of Zr by electron beam heating vapor deposition It has a film | membrane, The film | membrane covers 70 to 90% of the total area on the at least 1 main surface of the said sheet-like paper, It is characterized by the above-mentioned.

If the Cu content is less than 70% by mass, the cost increases in relation to the cost of other metals used, and if it exceeds 90% by mass, discoloration due to changes over time becomes severe.
One or more elements selected from the group consisting of Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, Zr are necessary in consideration of antibacterial properties, vapor deposition gloss color, manufacturing cost, etc. Appropriate selection may be made according to the situation.
When the adhesion amount of the copper alloy composition is less than 30 mg / m ² , the antibacterial property is insufficient, and when it exceeds 94 mg / m ² , the deposited film tends to be continuous.
When the coverage area ratio of the non-dense film that is not continuous is less than 70% of the total area on the sheet main surface, the antibacterial property is insufficient, and when it exceeds 90%, the printability and the readability are deteriorated.

In the present invention, the discontinuous and non-dense film is not a continuous dense vapor-deposited film, but has surface homogeneity, and the film surface has an arithmetic average surface roughness Ra of 0.02 to 0.02. The maximum height Rz is 0.2 to 0.5 μm at 0.1 μm, and the ratio Rq / Rz of the root mean square roughness Rq to the maximum height Rz is 0.3 to 1.3. .
When the arithmetic average surface roughness Ra is less than 0.02 μm, the printability and the readability are deteriorated. When the arithmetic average surface roughness Ra is more than 0.1 μm, the surface becomes rough and the touch feeling is deteriorated.
When the maximum height Rz is less than 0.2 μm, the printability and the readability are deteriorated, and when it exceeds 0.5 μm, the surface becomes rough and the touch feeling is deteriorated.
When the ratio Rq / Rz of the root mean square roughness Rq to the maximum height Rz exceeds 1.3, the film homogeneity is lost, and when it is less than 0.3, the homogeneity is saturated.

The antibacterial paper manufacturing method of the present invention includes an electron beam generating mechanism for generating an electron beam, a vapor deposition material holding part for holding a vapor deposition material at the irradiation position of the electron beam, and an outer peripheral surface with respect to the vapor deposition material holding part. A cooling drum that is provided to face a part of the cooling drum and is driven to rotate by a driving machine, and a paper traveling unit that travels the sheet-like paper in a state where the paper is wound around a part of the outer peripheral surface of the cooling drum, In an electron beam heating type vapor deposition apparatus having a vacuum vessel containing each of the above mechanisms, a plurality of crucibles each having a different melting point and constituting a copper alloy composition are separately fed into the traveling sheet. Installed in parallel in the width direction of the paper sheet, the electron beam is sequentially scanned and irradiated in the width direction of the traveling sheet paper on the plurality of crucibles, At least one A copper alloy composition containing one or more elements selected from the group consisting of Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, and Zr, containing 70% by weight or more of Cu on the surface 30 to 94 mg / m ^{2 is} attached to the product.

By this production method, 70 to 90% by mass of Cu is formed on at least one main surface of the sheet-like paper.
A copper alloy composition containing 10 to 30% by mass of one or more elements selected from the group consisting of Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, and Zr It has a non-consecutive non-dense film formed by depositing 30 to 94 mg / m ² by beam heating vapor deposition, and the film covers 70 to 90% of the total area on at least one main surface of the sheet-like paper. Antibacterial paper is produced that is characterized by
By sequentially scanning and irradiating the electron beam on a plurality of crucibles in the width direction of the traveling sheet paper, the surface is not a continuous dense deposited film on the main surface of the sheet paper, It has homogeneity, the arithmetic mean surface roughness Ra of the surface is 0.02 to 0.1 μm, the maximum height Rz is 0.2 to 0.5 μm, the root mean square roughness Rq and the maximum height A vapor deposition film having an Rz ratio Rq / Rz of 0.3 to 1.3 is formed.

In this case, since the melting point is different between Cu and other metal species forming the copper alloy composition, the residence time of the electron beam in the crucible containing Cu and the crucible containing other metal species is constant, and each crucible is fixed. By appropriately adjusting the electron beam irradiation area, or by adjusting the electron beam residence time in each crucible while keeping the electron beam irradiation area constant, vapor deposition of the target copper alloy composition Film formation is promoted.
In addition, it is preferable that the electron beam scan irradiation is not performed once but an appropriate number of scan irradiations is performed in order to form a vapor deposition film of a copper alloy composition which is a homogeneous object.

According to the present invention, the manufacturing cost is low, the printing property is excellent and the readability is high, Cu is contained in an amount of 70 to 90% by mass or more, Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Provided are a copper alloy antibacterial paper to which a copper alloy composition containing 10 to 30% by mass of one or more elements selected from the group consisting of Zn and Zr is attached in a discontinuous manner, and a method for producing the same.

It is a schematic cross section of the copper alloy adhesion antibacterial paper which is one Embodiment of this invention. It is the schematic which shows the electron beam heating type vapor deposition apparatus used in one Embodiment of the manufacturing method of this invention. It is a top view of the vapor deposition material holding | maintenance part used with the electron beam heating type vapor deposition apparatus used in one Embodiment of the manufacturing method of this invention.

The copper alloy adhesion antibacterial paper which is one embodiment of the present invention will be described in detail with reference to the accompanying drawings.
As shown in FIG. 1, the antibacterial paper 21 to which the copper alloy is attached according to the present invention has a discontinuous non-dense film 23 attached to the surface of a sheet-like paper 22 in an amount of 30 to 94 mg / m ^2. 70 to 90% of the total area of the paper 22.
The sheet-like paper 22 is thin paper, high-quality paper, drawing paper, Kent paper, and coated paper, and is generally paper for the purpose of recording on the surface thereof using a writing instrument such as a ballpoint pen. In particular, a high-quality PPC copy paper or the like is preferable.
The discontinuous non-dense film 23 contains 70 to 90% by mass of Cu, and one or more selected from the group consisting of Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, and Zr. A copper alloy composition containing 10 to 30% by mass of the above element is formed by adhering 30 to 94 mg / m ² on the surface of the sheet-like paper 22 by electron beam heating vapor deposition.
When the Cu content is less than 70% by mass, the cost increases. When the Cu content exceeds 90% by mass, discoloration due to aging becomes severe. From Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, Zr One or more elements selected from the group may be appropriately selected as necessary in consideration of antibacterial properties, vapor deposition gloss color, price, and the like.

When the adhesion amount is less than 30 mg / m ² , the antibacterial property is not sufficient, and when it exceeds 94 mg / m ² , the discontinuous non-dense film 23 tends to be continuous.
Further, when the coverage area ratio of the discontinuous non-dense film 23 is less than 70% of the area of the sheet-like paper 22, the antibacterial property is insufficient, and when it exceeds 90%, the printability and the readability are deteriorated.
The discontinuous non-dense 23 is not a continuous dense vapor-deposited film, but has homogeneity and has an arithmetic average surface roughness Ra of 0.02 to 0.1 μm and a maximum height Rz. Is 0.2 to 0.5 μm, and the ratio Rq / Rz of the root mean square roughness Rq to the maximum height Rz is 0.3 to 1.3.
When the arithmetic average surface roughness Ra is less than 0.02 μm, the printability and the readability are deteriorated, and when it exceeds 0.1 μm, the surface becomes rough and the touch is deteriorated.
When the maximum height Rz is less than 0.2 μm, the printability and the readability are deteriorated, and when it exceeds 0.5 μm, the surface becomes rough and the touch is deteriorated.
When the ratio Rq / Rz of the root mean square roughness Rq to the maximum height Rz exceeds 1.3, the uniformity of the film is lost. Below 0.3, the homogeneity tends to saturate.

FIG. 2 is a schematic view showing an example of an electron beam heating vapor deposition apparatus used in the production method of the present invention. Reference numeral 1 in the figure denotes a vacuum vessel, and the inside is decompressed by a vacuum pump (not shown). A cylindrical cooling drum 2 made of metal or the like is disposed in the center of the inside of the vacuum vessel 1 and is driven to rotate by a driving device (not shown).
A long sheet-like paper 5 is wound around a part of the outer peripheral surface of the cooling drum 2 in the drum circumferential direction and continuously travels between the uncoiler 3 and the recoiler 4. Opposite to the sheet-like paper winding part of the cooling drum 2, for example, as shown in FIG. 3, a vapor deposition material holding part 6 having a plurality of crucibles 8 is arranged, Cu in the crucible A and Ag in the crucible B. A kind of metal selected from the group consisting of Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, and Zr is accommodated. The crucible A and the crucible B are provided with crucible upper lids A1 and B1 at the upper part thereof, and are arranged on the side of the vapor deposition material holder 6 in consideration of the melting point of Cu and metal and the composition of the target copper alloy film The crucible openings A2 and B2 irradiated with the electron beam 12 generated by an electron beam generating mechanism (not shown) such as an electron gun are adjusted to optimum areas.
The electron beam 12 repeatedly irradiates A2 of the crucible A and B2 of the crucible B multiple times. By this scanning irradiation, the vapor 14 in which Cu from A2 and metal from B2 are alloyed with copper is deposited on the sheet-like paper 5 on the cooling drum 2.
A partition wall 16 is provided between the cooling drum 2 and the vapor deposition material holding unit 6 to regulate the vapor deposition range. The partition wall 16 has a semi-cylindrical portion 16A that accommodates the cooling drum 2. A constant space is provided between the inner peripheral surface of the semi-cylindrical portion 16A and the outer peripheral surface of the film winding portion of the cooling drum 2. A gap is formed. In the semi-cylindrical portion 16 </ b> A, a rectangular steam passage port 18 is formed in a position facing the vapor deposition material holding unit 6 toward the axial direction of the cooling drum 2. The vapor passage port 18 has the same overall length as the deposition width of the sheet-like paper 5.

Next, the manufacturing method of the copper alloy adhesion antibacterial paper of this invention using the said apparatus is demonstrated.
First, the pressure in the vacuum vessel 1 is set to 1 × 10 ⁻²
˜1 Pa, more preferably 5 × 10 ^{−2 to} 5 × 10 ^−1.
Equilibrate at Pa.
A crucible A containing Cu constituting a copper alloy composition in which the electron beam generating mechanism and the magnetic field generating mechanism 10 are operated and the electron beam 12 is installed in parallel in the width direction of the traveling sheet-like paper 5; By directly irradiating a plurality of times in the width direction of the traveling sheet-like paper 5 directly above the vapor deposition material holding unit 6 having the crucible B containing the metal, and continuously generating the copper alloyed vapor 14 The surface of the sheet-like paper 5 is not a dense vapor-deposited film continuous in the width direction of the sheet paper, but has a homogeneity, and the arithmetic average surface roughness Ra of the surface is 0.02 to 0.1 μm. Thus, a copper alloy vapor deposition film having a maximum height Rz of 0.2 to 0.5 μm and a ratio Rq / Rz of the root mean square roughness Rq to the maximum height Rz of 0.3 to 1.3 is formed.

In the above example, in order to obtain a desired homogeneous copper alloy composition, the irradiation area of each electron beam was appropriately adjusted in A2 of crucible A and B2 of crucible B. Alternatively, the residence time of the electron beam irradiation to the crucible B may be appropriately adjusted to obtain the intended homogeneous copper alloy composition.

Using the apparatus shown in FIG. 2 and the vapor deposition material holder shown in FIG. 3, put the Cu in the crucible A and the Zn in the crucible B under the following operating conditions on the surface of the copy paper for PPC. The antibacterial paper on which the copper zinc alloy was vapor-deposited was changed as shown in Table 1. Produced.
[Operating conditions]
Vacuum vessel pressure: 10-2 to 5x10-1 Pa
Oxygen introduction pressure: 1 × 10-1 Pa
Electron beam generation mechanism: Electron impact cathode type self-accelerating electron gun (90 ° deflection)
Acceleration voltage: 30 kV
Emission current: 2A
Scanning width of electron gun: 500mm
Number of scanning irradiations: 20 times Distance between vapor deposition material holding part and sheet-like paper: 250 mm
Outer diameter of cooling drum 2: 400 mm
Travel speed of sheet paper: 10 m / min

About each produced antibacterial paper, the area coverage of the copper zinc alloy vapor deposition film, the copper zinc alloy composition, and surface roughness Ra, Rz, Rq were measured.
The area coverage was confirmed from a scanned ion image (SIM image) of the antibacterial paper surface observed with a scanning ion microscope.
For the copper zinc alloy composition, the surface of the film was analyzed at 10 locations using an atomic absorption analyzer, and the average value was determined.
The surface roughness Ra, Rz, Rq is determined by irradiating the surface of the coating with laser light under the condition of an objective lens 100 times using a scanning confocal laser microscope LEXT OLS-3000 manufactured by Olympus Corporation. The distance was measured and obtained by continuously measuring the distance while scanning the laser beam linearly along the surface of the sample.
The results are shown in Table 1.

Moreover, it measured about printability, easy-to-read property, and antibacterial property about each obtained sample.
After printing with a commercially available inkjet printer (manufactured by Epson Corporation, PM-950C), the printability is wiped off with a tissue paper, and the state of the print mark is left as it is. Those that do not have a cross.
Easy-to-read is printed with a commercially available ink jet printer (manufactured by Epson, PM-950C), and the resulting print is visually observed. Difficult things were set as x.
Antibacterial activity, samples 100 cm ² cut was applied washed cells of Staphylococcus aureus to be 10 ⁵ to the copper alloy film side. The specimen obtained in this manner to count the number of bacteria after standing 24 hours at room, number of remaining bacteria and ○ those 300 / cm ² or less, and as × 300 / cm ² or more of .
The results are shown in Table 2.

表１、表２より、本発明の銅合金付着抗菌紙は、優れた印字性、易読性および抗菌性を有することがわかる。

From Tables 1 and 2, it can be seen that the copper alloy-attached antibacterial paper of the present invention has excellent printability, readability and antibacterial properties.

  As mentioned above, although the manufacturing method of embodiment of this invention was demonstrated, this invention is not limited to this description, A various change can be added in the range which does not deviate from the meaning of this invention.

21 Copper alloy antibacterial paper 22 Sheet-like paper 23 Discontinuous non-dense film 1 Vacuum container 2 Cooling drum 3 Uncoiler 4 Recoiler 5 Sheet-like paper 6 Vapor deposition material holding part 8 Crucible 10 Magnetic field generating mechanism 12 Electron beam 14 Copper alloy vapor 16 Bulkhead 16A Semi-cylindrical portion 18 Steam passage A A crucible B A crucible A1 A crucible upper lid B1 A crucible upper lid A2 A crucible opening B2 A crucible opening

Claims (2)

On at least one main surface of the sheet-like paper, 70 to 90% by mass of Cu is selected and selected from the group consisting of Ag, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, and Zr A non-continuous non-dense film formed by depositing 30 to 94 mg / m ^{2 of} a copper alloy composition containing 10 to 30% by mass of one or more elements by electron beam heating vapor deposition, An antibacterial paper which covers 70 to 90% of the total area on at least one main surface of a sheet-like paper. An electron beam generating mechanism for generating an electron beam; a vapor deposition material holding portion for holding a vapor deposition material at the irradiation position of the electron beam; and a part of an outer peripheral surface facing the vapor deposition material holding portion. A cooling drum that is driven to rotate, a paper traveling means that travels the sheet-like paper in a state in which the paper is wound around a part of the outer peripheral surface of the cooling drum, and a vacuum container that accommodates each of the above mechanisms. In the electron beam heating type vapor deposition apparatus, a plurality of crucibles each having a different melting point constituting the copper alloy composition are separately placed, and installed in parallel in the width direction of the traveling sheet-like paper, An electron beam is sequentially scanned and irradiated in the width direction of the traveling sheet on the plurality of crucibles, and Cu is 70% by weight or more on at least one main surface of the traveling sheet. Contains g, Al, Cr, Fe, Mg, Ni, Si, Sn, Ti, Zn, and making the copper alloy composition consisting of one or more elements selected from the group consisting of Zr 30~94mg / ^{m 2} is deposited The method for producing an antibacterial paper according to claim 1.

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