JP2007045035A - Shaft cylinder for writing implement - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shaft cylinder for a writing implement coated with a visible light type photo-catalyst excellent in response in the visible light region and good in transparency. <P>SOLUTION: A transparent or translucent shaft cylinder for the writing implement is characterized by forming a coating film layer of the visible light type photo-catalyst on the outer surface of the shaft cylinder by coating the outer surface of the shaft cylinder with a coating of the visible light type photo-catalyst comprising a titanium oxide fine particle with a mean particle diameter of 10-100 nm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a writing tool shaft made of transparent or semi-transparent, and more particularly to a writing tool shaft obtained by applying a visible light photocatalyst paint excellent in responsiveness in the visible light region.

  Conventionally, a writing instrument mixed with an antibacterial agent is disclosed in Japanese Patent Application Laid-Open No. 08-48097 “Anti-bacterial writing / applying tool”, Japanese Patent Application Laid-Open No. 2003-39873 “exterior part of writing tool”, and the like. Has molded an antibacterial agent into a molding material for molding a writing instrument part.

Various antibacterial agents used for these have been studied, but in order to use them as parts of writing instruments, it is necessary to consider moldability, safety, etc., and it is common to use a titanium oxide photocatalyst.
JP 08-48097 A JP 2003-39873 A

  However, conventional titanium oxide has a drawback that the wavelength of light that can be used for photocatalytic activity can only be used for ultraviolet rays of about 380 nm or less, and the range of use is limited.

  Therefore, if the wavelength of light that can be used can be extended to the visible light region, the photocatalytic activity can be exhibited even in an environment where the amount of ultraviolet rays is extremely low, such as indoors, and the application range of the photocatalyst can be expanded.

  Further, the conventional titanium oxide photocatalyst is contained in the molding material, has a large average particle size, has a problem in moldability and transparency, and has a problem that it is difficult to use it for a low-priced product or a transparent material.

  An object of the present invention is to provide a writing instrument shaft tube that is coated with a visible light type photocatalyst having excellent responsiveness in the visible light region and good transparency.

  The present invention provides a shaft of a writing instrument made of transparent or translucent, by applying a visible light photocatalyst paint containing titanium oxide fine particles having an average particle size of 10 nm or more and 100 nm or less to the outer surface of the shaft. A visible light photocatalyst film layer is formed on the outer surface of the cylinder.

  The visible light photocatalyst coating layer has a thickness of 1 μm or more and 30 μm or less.

  Further, the visible light type photocatalyst paint is composed of the titanium oxide fine particles, a hardly decomposable binder, and a solvent, and has a solid content concentration of 0.1% by mass or more and 10% by mass or less. And

  It was possible to provide a writing instrument shaft tube coated with a visible light type photocatalyst having excellent responsiveness in the visible light region and good transparency.

  Next, examples of the shaft cylinder of the writing instrument of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples.

  A shaft cylinder 1 of the writing instrument according to the present invention shown in FIG. 1 is a rotation formed by screwing a transparent front shaft 2 made of AS resin and a rear shaft 3 to form a shaft body, and formed by POM resin in the rear shaft 3. It is a shaft cylinder of a knock type writing instrument provided with a retracting mechanism comprising a cam 4. This intruding mechanism is conventionally known. Briefly, a cam groove (not shown) for sliding and guiding the rotating cam 4 back and forth on the inner wall surface of the rear end portion of the rear shaft 3 is rotated. ), And a protrusion formed on the rotating cam 4 is engaged with the cam groove. At the rear end of the rotating cam 4, a knock body 5 having a cam portion at the tip for sliding and imparting rotation to the rotating cam is arranged in a state protruding outward from the opening of the rear shaft rear end 3a. It is set up.

  In front of the rotating cam 4, a writing instrument refill 7 in which a ballpoint pen tip 10 is attached to the tip of an ink containing tube 8 made of PP resin containing writing instrument ink (not shown) via a tip holder 9 is spring-loaded. 6 is slidably disposed by being urged toward the rear shaft rear end 3a, and the writing shaft refill 7 can be replaced by removing the front shaft 2. In addition, a translucent grip member 11 is disposed on the grip portion of the front shaft 2.

  In order to use the knock type writing instrument 1, the knock body 5 is pressed to advance the rotating cam 4 along a cam groove (not shown), and the rotating cam 4 is rotated by the action of the cam portion of the knock body 5. The ballpoint pen tip 10 can be used by protruding from the tip opening 2a of the front shaft 2. When the knock body 5 is further pressed, the rotating cam 4 is rotated by the action of the cam portion of the knock body 5, and the rotating cam 4 is retracted along the cam groove (not shown) by the urging force of the spring 6. Can be immersive.

  The transparent front shaft 2 and rear shaft 3 are visible light photocatalysts containing titanium oxide fine particles having an average particle diameter of 30 nm on the outer surfaces of the front shaft 2 and the rear shaft 3 after the front shaft 2 and the rear shaft 3 are molded. A coating layer 12 of a visible light type photocatalyst having a thickness of 10 μm is formed on the outer surface of the main body of the shaft cylinder by applying and drying the paint.

  In the visible light type photocatalyst coating used in the present invention, fine titanium oxide particles having a visible light response with a wavelength of 420 nm or more are used as the visible light type photocatalyst. The titanium oxide fine particles are not particularly limited as long as they have visible light responsiveness. For example, anatase type visible light responsive titanium oxide fine particles or rutile type visible light responsive titanium oxide fine particles may be used. it can. Since these visible light-responsive titanium oxide fine particles have visible light responsiveness, the photocatalytic function is exhibited by artificial light including visible light such as a fluorescent lamp and natural light including visible light.

  If the average particle diameter of the titanium oxide fine particles is less than 10 nm, sufficient antibacterial effect cannot be expected with natural light including visible light, and if it exceeds 100 nm, the surface may lose transparency due to scattering of visible light by the particles. At the same time, since the gap between the particles is large, there are many portions where the photocatalytic function cannot be exhibited by natural light including visible light, so the average particle diameter of the titanium oxide fine particles is 10 nm or more and 100 nm or less. The average particle diameter of the titanium oxide fine particles can be determined by, for example, a dynamic laser scattering method.

  Therefore, by forming the coating layer 12 of visible light photocatalyst containing titanium oxide fine particles having an average particle diameter of 10 nm or more and 100 nm or less on the shaft cylinder body made of transparent AS resin, the inside of the front shaft 1 and the rear shaft 3 The refill 7 for a writing instrument can be visually recognized, and the remaining ink amount in the ink containing tube 8 made of transparent PP resin can be confirmed from the outside.

  When the film thickness of the visible light type photocatalyst coating layer 12 is less than 1 μm, the coating method is difficult and the antibacterial effect is small, and when it exceeds 30 μm, the concealability is high and the transparency may be lost. Therefore, the film thickness of the coating layer 12 of the visible light type photocatalyst is preferably 1 μm or more and 30 μm or less.

  As a visible light type photocatalyst coating using visible light responsive titanium oxide fine particles that can be specifically used, for example, Blue Active PW25 (BA-PW25, manufactured by Ecodevices), TPS (manufactured by Sumitomo Chemical Co., Ltd.), etc. Is mentioned.

  The visible light type photocatalyst coating material contains titanium oxide fine particles having an average particle size of 10 nm or more and 100 nm or less, a hardly decomposable binder such as silicone or silica fine particles, and a solvent. A leveling agent, a surfactant, an antibacterial metal, a pH adjuster, a storage stabilizer and the like can be added to the visible light type photocatalyst paint.

  The solvent that can be used for the visible light type photocatalyst coating is not limited as long as the titanium oxide fine particles are stably dispersed and a hydrophilic surface can be finally obtained, and examples thereof include water and / or an organic solvent. Water or alcohol or a mixed solvent thereof is particularly preferable. As the alcohol, methanol, ethanol, n-propanol, isopropanol, butanol, pentaanol and the like can be used.

  The solid content concentration of the visible light photocatalyst paint is preferably 0.1% by mass or more and 10% by mass or less. When the solid content concentration exceeds 10% by mass, the surface to which the composition is applied has a white turbid appearance, which may impair transparency, and the solid content concentration is less than 0.1% by mass. This is because the photocatalytic function may not be efficiently expressed by natural light including visible light.

  In the present invention, the visible light photocatalyst paint described above is only applied to the outer surface of the shaft tube and dried to form a coating layer, which affects the moldability as compared with the conventional method of mixing with a resin material and molding. The shaft of the writing instrument can be easily obtained without any problem.

  The method for forming the coating layer of the present invention is as follows. If the visible light photocatalyst paint described above is applied to the outer surface of the shaft tube and dried to obtain a coating layer, a spin coating method, a doctor blade method, a dipping method, a brush coating, The application method is not particularly limited, such as a spray method or a roll coater method. Although not shown, an inorganic base layer may be formed on the outer surface of the shaft tube, and a visible light photocatalyst paint may be applied on the base layer and dried to form a coating layer.

  Although not shown, the above-mentioned visible light type photocatalyst paint is applied not only to the outer surface of the shaft tube but also to the inner wall surface of the shaft tube, and dried to form a coating layer. Also good.

  Since it has a coating layer of visible light photocatalyst, it has an antibacterial action even in a room, so it is suitable as a writing instrument used by an unspecified number of people in public places such as government offices, hospitals, and schools.

It is a longitudinal cross-sectional view which shows the axial cylinder of the writing instrument of Example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Writing tool cylinder 2 Front shaft 3 Rear shaft 4 Rotating cam 5 Knock body 6 Coil spring 7 Refill for writing tool 8 Ink storage tube 9 Tip holder 10 Ball-point pen tip 11 Grip 12 Film layer

Claims (3)

In a writing cylinder made of transparent or semi-transparent, by applying a visible light type photocatalyst paint containing titanium oxide fine particles having an average particle diameter of 10 nm or more and 100 nm or less to the outer surface of the shaft cylinder, A writing tube shaft characterized in that a visible light photocatalyst coating layer is formed. The shaft cylinder of the writing instrument according to claim 1, wherein the thickness of the coating layer of the visible light type photocatalyst is 1 µm or more and 30 µm or less. The visible light type photocatalyst coating material comprises the titanium oxide fine particles, a hardly decomposable binder, and a solvent, and has a solid content concentration of 0.1% by mass or more and 10% by mass or less. The shaft cylinder of the writing instrument according to claim 1 or 2.

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