JP2017105051A - Knock-type writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a knock-type writing utensil that can relax shock which is applied to a refill when switching a writing state into a non-writing state, with a simple mechanism.SOLUTION: A knock-type writing utensil 1 comprises a barrel 2, a refill 4 arranged in the barrel 2, a spring 5 for energizing the refill 4 rearward, and an operation part 3 which is pressed forward against energizing force of the spring 5 at the time of knocking operation, where on an outer surface of the refill 4 is arranged a braking member 10 that brakes the refill 4 in cooperation with the barrel 2 when the refill 4 is retreated by the knocking operation.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a knock-type writing instrument.

  A refill containing ink by a knock operation that has an operation portion at the rear end of the shaft tube and presses the operation portion forward against the urging force of a spring disposed in the shaft tube, that is, writing There is known a knock-type writing instrument that is a so-called knock type in which a writing state in which a writing portion that is a body nib protrudes from the tip of a shaft tube and a non-writing state in which the writing portion is immersed in the shaft tube are switched.

  In general, in a knock type writing instrument, bubbles may be generated in ink in a refill due to an impact applied to the refill when switching from a writing state to a non-writing state. That is, when switching from the writing state to the non-writing state, the refill moves vigorously backward by the urging force of the spring, and an impact is applied when the refill is stopped. In particular, when low viscosity ink or shear thinning ink is contained in the refill, the ink may retreat due to the impact, and air may be mixed into the refill from the writing portion. In this case, bubbles may be generated in the ink, which may cause poor writing. (Hereinafter, the phenomenon that air is mixed into the refill due to the ink retreating is referred to as “ink back”.)

  In view of this, the knock type writing instrument described in Patent Document 1 has an elastic body disposed in the shaft cylinder behind the refill in order to absorb the impact of the refill that has been moved rearward by the urging force of the spring.

JP-A-8-164597

  However, in Patent Document 1, since the elastic body is disposed behind the refill, it is necessary to secure a space corresponding to the volume of the elastic body in the shaft cylinder, and therefore, it is necessary to shorten the total length of the refill. . As a result, the amount of ink that can be stored is reduced, and the writable distance is shortened. Moreover, since the timing at which the impact during the switching to the non-writing state is absorbed is when the refill has come to the vicinity of the retreat limit position, the kinetic energy is in the highest state. Therefore, although it is absorbed by the elastic body, the refill is not a little impacted.

  An object of the present invention is to provide a knock-type writing instrument that can relieve an impact applied to a refill at the time of switching to a non-writing state by a simple mechanism.

  According to one aspect of the present invention, a shaft tube, a writing body disposed in the shaft tube, an elastic member that biases the writing body rearward, and a biasing force of the elastic member during a knocking operation. A knock-type writing instrument having an operation portion that is pushed forward against the outer surface of the writing body, and when the writing body is retracted by a knocking operation, the writing body cooperates with the shaft cylinder. A knock type writing instrument is provided, which is provided with a braking section for performing braking.

  Moreover, according to another aspect, the said braking part has a processus | protrusion.

  Moreover, according to another aspect, it has a contact part which contact | abuts the said protrusion in the internal peripheral surface of the said axial cylinder.

  According to another aspect, the contact portion is a protrusion formed in an annular shape on the inner peripheral surface of the shaft tube.

  Moreover, according to another aspect, the said braking part is a separate cylindrical member which can be attached or detached with respect to the said writing body.

  Moreover, according to another aspect, the some rib which hold | maintains the said writing body is formed in the internal peripheral surface of the said cylindrical member.

  According to the aspect of the present invention, there is a common effect that the impact applied to the refill can be reduced by the simple mechanism when switching to the non-writing state. Further, it is possible to prevent the occurrence of ink back.

It is a fragmentary sectional view of the writing state of the knock type writing instrument by a 1st embodiment of the present invention. It is an expanded sectional view of the front-end | tip part in the writing state of the knock type writing instrument of FIG. It is an expanded sectional view of the front-end | tip part in the non-writing state of the knock type writing instrument of FIG. It is a perspective view of the braking member of the knock type writing instrument of FIG. It is a longitudinal cross-sectional view of the braking member of FIG. It is a fragmentary sectional view of the writing state of the knock type writing instrument by a 2nd embodiment of the present invention. It is an expanded sectional view of the part A of FIG. It is a perspective view of the braking member of the knock type writing instrument of FIG. It is a longitudinal cross-sectional view of the braking member of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Corresponding components are denoted by common reference symbols throughout the drawings.

  FIG. 1 is a partial cross-sectional view of the writing state of the knock type writing instrument 1 according to the first embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of the distal end portion in the writing state of the knocking type writing instrument 1 of FIG. FIG. 3 is an enlarged cross-sectional view of the tip portion of the knock type writing instrument 1 of FIG. 1 in a non-writing state. The knock-type writing instrument 1 is a refill 4 that is a writing body including a cylindrical tube 2 that is a cylindrical member, an operation unit 3 that is provided at the rear end of the cylindrical tube 2, and a writing unit 4 a. And have. In the present specification, in the axial direction of the knock type writing instrument 1, the writing portion 4a side is defined as the “front” side, and the opposite side of the writing portion 4a is defined as the “rear” side.

  The refill 4 is urged rearward by a spring 5 that is an elastic member disposed in the shaft cylinder 2. The knock type writing instrument 1 has a known knock mechanism. By performing a knocking operation that pushes the operation portion 3 forward against the urging force of the spring 5, the writing portion 4 a of the refill 4 protrudes from the tip of the shaft tube 2 and the writing portion 4 a is within the shaft tube 2. You can switch between the non-written state that you are immersed in.

  The operation unit 3 includes a cover member 6 exposed to the outside, and an erasing member (not shown) disposed inside the cover member 6 and covered with the cover member 6. The handwriting by the knock type writing instrument 1 can be erased using the erasing member. The operation unit 3 itself may be configured as an erasing member.

  The refill 4 includes the writing portion 4a described above, a tubular refill body 4b, and a joint member 4c that connects the writing portion 4a and the tubular refill body 4b. A braking member 10, which is a tubular member, is provided as a braking portion at the distal end portion of the refill 4, that is, the outer peripheral surface of the joint member 4 c.

  4 is a perspective view of the braking member 10 of the knock type writing instrument 1 of FIG. 1, and FIG. 5 is a longitudinal sectional view of the braking member 10 of FIG. In FIG. 5, the braking member 10 is provided with respect to the refill 4 so that the left side is the front side of the knock type writing instrument 1 and the right side is the rear side of the knock type writing instrument 1.

  An annular flange portion 11 is formed at the rear end portion of the outer peripheral surface of the braking member 10. Four protrusions 12 are formed on the outer circumferential surface of the flange portion 11 so as to be evenly arranged along the circumferential direction. Further, four ribs 13 are formed on the inner peripheral surface of the flange portion 11 so as to protrude radially inward and to be evenly arranged along the circumferential direction. In the rear end portion of the braking member 10, that is, in the vicinity of the flange portion 11, a thin portion 14 that is thinner than the rib 13 and a connection portion 15 that connects the rib 13 and the thin portion 14 are formed. Further, the protrusion 12 is formed on the outer peripheral surface of the flange portion 11 corresponding to the thin portion 14.

  The rib 13 has a holding surface 13 a configured to guide the refill 4 inserted or press-fitted from the rear end opening of the braking member 10. In addition, a guide surface 13b that is inclined with respect to the central axis is formed in a portion of the rib 13 in the vicinity of the rear end opening of the braking member 10. When the refill 4 is inserted, the writing portion 4a of the refill 4 is guided by the guide surface 13b. On the front end surface of the rib 13, a spring support surface 13c perpendicular to the central axis is formed.

  The flange part 11 has flexibility with respect to a radial force by forming the thin part 14 and the connection part 15. Therefore, when the refill 4 is provided on the braking member 10, the thin portion 14 and the connection portion 15 can be elastically deformed radially outward so that the rib 13 holds the refill 4 firmly, and can be expanded. Further, as will be described later, when the braking member 10 brakes the refill 4, the protrusion 12 can move radially inward along with the elastic deformation of the thin portion 14 and the connecting portion 15.

  The braking member 10 will be described in more detail with reference to FIGS. 2 and 3 again. The braking member 10 is provided at a position where the rear end surface thereof abuts on the step 4 d of the joint member 4 c of the refill 4. The front end of the spring 5 is supported by a step 2 a formed on the inner surface of the shaft cylinder 2, and the rear end of the spring 5 is supported by a spring support surface 13 c of the braking member 10. That is, the refill 4 is urged rearward by the spring 5 via the braking member 10. An annular protrusion 7 is formed on the inner peripheral surface of the shaft cylinder 2 as a contact portion that contacts the protrusion 12 of the braking member 10.

  In the writing state of the knock-type writing instrument 1 shown in FIG. 2, when a knocking operation is performed to press the operation unit 3, the refill 4 is vigorously moved backward by the urging force of the spring 5. When the refill 4 moves backward, the protrusion 12 of the braking member 10 and the annular protrusion 7 of the shaft cylinder 2 come into contact with each other. In other words, the axial position of the annular protrusion 7 of the shaft cylinder 2 is set so that the protrusion 12 of the braking member 10 and the annular protrusion 7 of the shaft cylinder 2 abut when the refill 4 is retracted, and the braking member 10 The size of the projection 12 or the annular projection 7 of the shaft cylinder 2 is set.

  When the protrusion 12 of the braking member 10 and the annular protrusion 7 of the shaft cylinder 2 come into contact, due to the shape of the protrusion 12 and the annular protrusion 7, that is, the curved surface shape, the radially inward direction relative to the protrusion 12 of the braking member 10 The power of. At this time, the thin portion 14 and the connecting portion 15 of the braking member 10 are elastically deformed according to the retreat of the refill 4, so that the protrusion 12 of the braking member 10 rides over the annular protrusion 7 of the shaft tube 2. Move backwards. The resistance force, that is, the frictional force due to the sliding of the protrusion 12 of the braking member 10 with respect to the annular protrusion 7 of the shaft cylinder 2 decelerates the refill 4 from retreating. As a result, the kinetic energy of the refill 4 is reduced, and finally the impact received by the refill 4 is reduced. Therefore, it is possible to minimize the occurrence of problems such as poor writing due to impact.

  The spring characteristics and arrangement of the spring 5 are selected so that the refill 4 is urged against the frictional force described above, and the knocking writing instrument 1 can be switched from the writing state to the non-writing state.

  In the non-writing state of the knock type writing instrument 1, the axial distance between the front end surface of the shaft cylinder 2 and the tip of the writing portion 4 a is X, and the axial direction between the protrusion 12 of the braking member 10 and the annular protrusion 7 of the shaft cylinder 2. If the distance is Y, X> Y is preferable. On the other hand, when X <Y, when the refill 4 moves backward, if the refill 4 stops because the projection 12 of the braking member 10 cannot get over the annular projection 7 of the shaft cylinder 2, the writing unit 4 a Is exposed from the shaft tube 2. As a result, X> Y is preferable because there is a possibility that clothes may be soiled, such as when the knocking writing instrument 1 is put in a pocket.

  FIG. 6 is a partial cross-sectional view in a writing state of the knock type writing instrument 20 according to the second embodiment of the present invention, and FIG. 7 is an enlarged cross-sectional view of a portion A in FIG. The knock-type writing instrument 20 has another braking member 30 instead of the braking member 10 of the knock-type writing instrument 1 according to the first embodiment described above. That is, in the knock type writing instrument 20, the braking member 30 that is a cylindrical member is detachably attached as a braking portion to the outer peripheral surface of the refill main body 4b of the refill 4 instead of the joint member 4c at the tip of the refill 4. Yes.

  Another annular protrusion 8 is formed on the inner peripheral surface of the shaft cylinder 2 as an abutting portion that abuts against a protrusion 33 of a braking member 30 described later. About the other structure of the knock type writing instrument 20, since it is the same as that of the knock type writing instrument 1 of 1st Embodiment, description is abbreviate | omitted. In addition, the braking member 30 of this embodiment can also be used in one knock type writing instrument together with the braking member 10 of the first embodiment.

  FIG. 8 is a perspective view of the braking member 30 of the knock type writing instrument 20 of FIG. 6, and FIG. 9 is a longitudinal sectional view of the braking member 30 of FIG. In FIG. 9, the braking member 30 is attached to the refill 4 so that the left side is the front side of the knock type writing instrument 20 and the right side is the rear side of the knock type writing instrument 20.

  The outer peripheral surface of the braking member 30 has two claw portions 32 defined by a U-shaped through groove 31 when viewed from the side with the front side of the braking member 30 facing up. The two claw portions 32 are disposed to face each other on the outer peripheral surface. A protrusion 33 is formed at the rear end portion of the outer surface of the claw portion 32 along the edge of the rear end. That is, the braking member 30 has two protrusions 33. An annular flange portion 34 is formed at the front end portion of the outer peripheral surface of the braking member 30. The front end portion of the claw portion 32 is connected to the flange portion 34. Since the claw portion 32 can be elastically deformed outward and inward in the radial direction from the connection portion with the flange portion 34, the projection 33 of the claw portion 32 is also movable inward in the radial direction.

  Four ribs 35 are formed on the inner peripheral surface of the braking member 30 along the axial direction. The rib 35 has a holding surface 35 a configured to hold the refill 4 inserted from the rear end opening of the braking member 30. The rib 35 near the rear end opening of the braking member 30 is formed with a guide surface 35b oblique to the central axis. When the refill 4 is inserted, the refill 4 is guided by the guide surface 35b.

  The braking member 30 decelerates the retreat of the refill 4 in the same manner as the braking member 10 of the first embodiment described above. That is, when the refill 4 is retracted, the protrusion 33 of the braking member 30 and the annular protrusion 8 of the shaft cylinder 2 come into contact with each other. In other words, the axial position of the annular protrusion 8 of the shaft tube 2 is set so that the protrusion 33 of the braking member 30 and the annular protrusion 8 of the shaft tube 2 abut when the refill 4 is retracted, and the braking member 30 The size of the projection 33 or the annular projection 8 of the shaft cylinder 2 is set. Further, the relationship between X and Y described with reference to FIG. That is, if the distance in the axial direction between the protrusion 33 of the braking member 30 and the annular protrusion 8 of the shaft cylinder 2 is Z, it is preferable that X> Z.

  When the refill 4 is retracted, the claw portion 32 is elastically deformed according to the refill 4 retracting, so that the projection 33 of the braking member 30 moves backward so as to ride over the annular projection 8 of the shaft cylinder 2. . The resistance force, that is, the frictional force caused by the sliding of the protrusion 12 of the braking member 10 with respect to the annular protrusion 8 of the shaft cylinder 2 decelerates the refill 4 from moving backward. As a result, the kinetic energy of the refill 4 is reduced, and finally the impact received by the refill 4 is reduced. Therefore, it is possible to minimize the occurrence of problems such as poor writing due to impact.

  According to the embodiment of the present invention described above, the braking portion that brakes the refill 4 in cooperation with the shaft cylinder 2 when the refill 4 is retracted by the knocking operation on the outer surface of the refill 4, that is, the braking member 10 or the braking member. Since 30 is provided, the impact applied to the refill 4 can be reduced by a simple mechanism.

  The braking member described above is formed from a resin material such as polyacetal. In addition, since the braking member is separate from the refill 4, the braking member can be applied to the existing refill. However, the braking member may be formed integrally with the refill.

  As long as the brake member or the shaft cylinder 2 cooperates with each other, any configuration can be adopted. For example, the number of the protrusions 12 or the protrusions 33 of the braking member may be one, three, or five or more. As long as the annular protrusion 7 or the annular protrusion 8 provided on the shaft cylinder 2 is in contact with the protrusion of the braking member, the annular protrusion 7 or the annular protrusion 8 may not be an annular protrusion. For example, the inner diameter of the shaft tube 2 may be gradually decreased toward the rear, and the inner peripheral surface of the shaft tube 2 may be brought into contact with the protrusion of the braking member when the refill 4 is retracted. Further, at this time, the braking member may not have a protrusion, and the outer surface may simply be brought into contact with the inner peripheral surface having a smaller inner diameter.

  The refill 4 in the above-described embodiment may contain a thermochromic ink containing a thermochromic color material. In this case, the knock-type writing instrument is a knock-type thermochromic writing instrument, and the handwriting of the knock-type writing instrument can be thermally discolored by frictional heat generated when it is rubbed by a friction body as an erasing member.

  Here, the thermochromic ink means that a predetermined color (first color) is maintained at room temperature (for example, 25 ° C.), and when the temperature is raised to a predetermined temperature (for example, 60 ° C.), the color changes to another color (second color). The ink has a property of returning to the original color (first color) when cooled to a predetermined temperature (for example, −5 ° C.). In the knock type writing instrument using thermochromic ink, the second color is made colorless, and the stroke drawn with the first color (for example, red) is heated to make it colorless, which is referred to as “erasing” here. To do. Accordingly, the frictional body rubs against the writing surface on which the drawn line is written to generate frictional heat, thereby changing the drawn line to colorless, that is, erasing it. Of course, the second color may be a color other than colorless.

  As the thermochromic microcapsule pigment that becomes a thermochromic color material, those that change color due to heat such as frictional heat, for example, those that have a function from colored to colorless, colored to colored, colorless to colored, etc. There are no particular limitations, and various types can be used. Examples include microencapsulated thermochromic compositions containing at least a leuco dye, a developer, and a color change temperature adjusting agent.

  The leuco dye that can be used is not particularly limited as long as it is an electron donating dye and functions as a color former. Specifically, from the viewpoint of obtaining an ink having excellent color development characteristics, conventionally known ones such as triphenylmethane, spiropyran, fluoran, diphenylmethane, rhodamine lactam, indolylphthalide, leucooramine, It can be used alone (one kind) or in a mixture of two or more kinds (hereinafter simply referred to as “at least one kind”).

  Specifically, 6- (dimethylamino) -3,3-bis [4- (dimethylamino) phenyl] -1 (3H) -isobenzofuranone, 3,3-bis (p-dimethylaminophenyl) -6 -Dimethylaminophthalide, 3- (4-diethylaminophenyl) -3- (1-ethyl-2-methylindol-3-yl) phthalide, 3- (4-diethylamino-2-ethoxyphenyl) -3- (1 -Ethyl-2-methylindol-3-yl) -4-azaphthalide, 1,3-dimethyl-6-diethylaminofluorane, 2-chloro-3-methyl-6-dimethylaminofluorane, 3-dibutylamino-6 -Methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-xylidinofluor Lan, 2- (2-chloroanilino) -6-dibutylaminofluorane, 3,6-dimethoxyfluorane, 3,6-di-n-butoxyfluorane, 1,2-benz-6-diethylaminofluorane, 1 , 2-Benz-6-dibutylaminofluorane, 1,2-Benz-6-ethylisoamylaminofluorane, 2-methyl-6- (Np-tolyl-N-ethylamino) fluorane, 2- (N -Phenyl-N-methylamino) -6- (Np-tolyl-N-ethylamino) fluorane, 2- (3'-trifluoromethylanilino) -6-diethylaminofluorane, 3-chloro-6 -Cyclohexylaminofluorane, 2-methyl-6-cyclohexylaminofluorane, 3-di (n-butyl) amino-6-methoxy-7-anilinofluorane 3,6-bis (diphenylamino) fluorane, methyl-3 ′, 6′-bisdiphenylaminofluorane, chloro-3 ′, 6′-bisdiphenylaminofluorane, 3-methoxy-4-dodecoxystyrino Quinoline, etc.

  These leuco dyes have a lactone skeleton, a pyridine skeleton, a quinazoline skeleton, a bisquinazoline skeleton, etc., and develop color when these skeletons (rings) are opened.

  The developer that can be used is a component having the ability to develop the leuco dye, such as a phenol resin compound, a salicylic acid metal chloride, a salicylic acid resin metal salt compound, a solid acid compound, etc. Is mentioned.

  Specifically, o-cresol, tertiary butyl catechol, nonylphenol, n-octylphenol, n-dodecylphenol, n-stearylphenol, p-chlorophenol, p-bromophenol, o-phenylphenol, hexafluorobisphenol, p N-butyl hydroxybenzoate, n-octyl p-hydroxybenzoate, resorcin, dodecyl gallate, 2,2-bis (4′-hydroxyphenyl) propane, 4,4-dihydroxydiphenyl sulfone, 1,1-bis (4′-hydroxyphenyl) ethane, 2,2-bis (4′-hydroxy-3-methylphenyl) propane, bis (4-hydroxyphenyl) sulfide, 1-phenyl-1,1-bis (4′-hydroxy Phenyl) ethane, 1,1-bis ( 4′-hydroxyphenyl) -3-methylbutane, 1,1-bis (4′-hydroxyphenyl) -2-methylpropane, 1,1-bis (4′-hydroxyphenyl) n-hexane, 1,1-bis (4′-hydroxyphenyl) n-heptane, 1,1-bis (4′-hydroxyphenyl) n-octane, 1,1-bis (4′-hydroxyphenyl) n-nonane, 1,1-bis (4 '-Hydroxyphenyl) n-decane, 1,1-bis (4'-hydroxyphenyl) n-dodecane, 2,2-bis (4'-hydroxyphenyl) butane, 2,2-bis (4'-hydroxyphenyl) ) Ethyl propionate, 2,2-bis (4′-hydroxyphenyl) -4-methylpentane, 2,2-bis (4′-hydroxyphenyl) hexafluoropropane, 2 2- bis (4'-hydroxyphenyl) n- heptane, 2,2-bis least one such (4'-hydroxyphenyl) n- nonane and the like.

  The amount of the developer to be used may be arbitrarily selected according to the desired color density and is not particularly limited, but is usually 0.1 to 1 part by mass of the leuco dye described above. It is preferable to select within a range of about 100 parts by mass.

  The color change temperature adjusting agent that can be used is a substance that controls the color change temperature in the coloration of the leuco dye and the developer. Conventionally known color change temperature adjusting agents can be used. Specific examples include alcohols, esters, ketones, ethers, acid amides, azomethines, fatty acids, hydrocarbons and the like.

More specifically, bis (4-hydroxyphenyl) phenylmethane dicaprylate (C ₇ H ₁₅ ), bis (4-hydroxyphenyl) phenylmethane dilaurate (C ₁₁ H ₂₃ ), bis (4-hydroxyphenyl) phenyl Methane dimyristate (C ₁₃ H ₂₇ ), bis (4-hydroxyphenyl) phenylethane dimyristate (C ₁₃ H ₂₇ ), bis (4-hydroxyphenyl) phenylmethane dipalmitate (C ₁₅ H ₃₀ ), bis Examples thereof include at least one of (4-hydroxyphenyl) phenylmethane dibehenate (C ₂₁ H ₄₃ ) and bis (4-hydroxyphenyl) phenylethylhexylidene dimyristate (C ₁₃ H ₂₇ ).

  The amount of the color-change temperature adjusting agent used may be appropriately selected according to the desired hysteresis width and color density at the time of color development, and is not particularly limited, but is usually based on 1 part by mass of the leuco dye. It is preferable to use within the range of about 1 to 100 parts by mass.

  The thermochromic microcapsule pigment is obtained by microencapsulating a thermochromic composition containing at least the leuco dye, the developer, and the color change temperature adjusting agent so that the average particle diameter is 0.2 to 3 μm. Can be manufactured. Examples of the microencapsulation method include interfacial polymerization method, interfacial polycondensation method, in situ polymerization method, liquid curing coating method, phase separation method from aqueous solution, phase separation method from organic solvent, melt dispersion cooling method, air A suspension coating method, a spray drying method, etc. can be mentioned, and can be appropriately selected according to the application.

  For example, in a phase separation method from an aqueous solution, a leuco dye, a developer, and a color change temperature adjusting agent are heated and melted, then charged into an emulsifier solution, heated and stirred to disperse into oil droplets, and then as a capsule film agent, Use resin raw materials, for example, gradually add amino resin solution, isocyanate resin solution, etc., and continue to react to prepare, then filter this dispersion to produce the desired thermochromic microcapsule pigment be able to.

  The content of these leuco dyes, developer, and color change temperature adjusting agent varies depending on the type of leuco dye, developer, color change temperature adjusting agent used, microencapsulation method, etc. The developer is 0.1 to 100 developer and 1 to 100 color changing temperature adjusting agent in mass ratio. Moreover, a capsule membrane agent is 0.1-1 by mass ratio with respect to the capsule content.

  The thermochromic microcapsule pigment is a combination of the above-described leuco dye, color developer, and color change temperature adjusting agent, and the amount, color development temperature of each color (for example, color development at 0 ° C. or higher), decolorization temperature ( For example, it is possible to set the color erasing at 50 ° C. or higher) to a suitable temperature, and it is preferable that the color changes from colored to colorless by heat such as frictional heat.

  In the thermochromic microcapsule pigment, the wall film is preferably formed of a urethane resin, a urea / urethane resin, an epoxy resin, or an amino resin from the viewpoint of further improving the drawing density, storage stability, and writing property. As a urethane resin, the compound of isocyanate and a polyol is mentioned, for example. As an epoxy resin, the compound of an epoxy resin and an amine is mentioned, for example. Examples of amino resins include melamine resins, urea resins, and benzoguanamine resins. The thickness of the wall film of the microcapsule coloring material is appropriately determined according to the required strength of the wall film and the drawn line density.

  The average particle size of the thermochromic microcapsule pigment is low in color, color developability, easy decoloring, stability, fluidity in ink, and adverse effects on writing properties. From the viewpoint of compatibility with the microcapsule pigment, it is preferably 0.2 to 5 μm, and more preferably 0.3 to 3 μm. The “average particle diameter” defined here is a value obtained by measuring the average particle diameter (50% diameter) with a particle size analyzer [Microtrac HRA9320-X100 (Nikkiso Co., Ltd.)] (refractive index 1.8). It is.

  If the average particle size is less than 0.2 μm, sufficient line density cannot be obtained. On the other hand, if it exceeds 5 μm, the writing property is deteriorated, the dispersion stability of the thermochromic microcapsule pigment is lowered, and the ink is caused by vibration. Back is likely to occur, which is not preferable. Further, the 90% diameter is 8 μm or less, preferably 6 μm or less. When particles having a large diameter are present in a certain ratio or more, the above-described influence tends to become more prominent. In addition, although the microcapsule pigment having an average particle diameter range (0.2 to 5 μm) described above varies depending on the microencapsulation method, in the phase separation method from an aqueous solution, stirring when the microcapsule pigment is produced. It can be prepared by suitably combining conditions.

  The specific gravity of the thermochromic microcapsule pigment is in the range of 0.9 to 1.3, preferably 1.0 to 1.2. If the specific gravity is outside this range, the dispersion stability of the microcapsule pigment tends to be lowered. In addition, microcapsule pigments having a specific gravity exceeding 1.3 are liable to generate ink back due to vibration.

  In the water-based ink composition for writing instruments, in addition to the thermochromic microcapsule pigment, the balance is water (tap water, purified water, distilled water, ion-exchanged water, pure water, etc.), and other writing instruments (ballpoint pens) Depending on the purpose of use, for marking pens, etc., water-soluble organic solvents, thickeners, lubricants, rust preventives, antiseptics or antibacterial agents may be appropriately contained within a range that does not impair the effect. it can.

  Examples of water-soluble organic solvents that can be used include glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, polyethylene glycol, 3-butylene glycol, thiodiethylene glycol, and glycerin, ethylene glycol monomethyl ether, and diethylene glycol monomethyl. Ethers can be used alone or in combination.

  Among these, glycerin is preferably used for the purpose of suppressing ink solidification in the writing portion due to ink back, and the amount added is preferably 1 to 10% by mass with respect to the total amount of ink. Although the mechanism of action by glycerin is unknown, it is presumed that it has the effect of reducing the cohesive strength with the pigment and ink components in the dry state.

  As the thickener that can be used, for example, at least one selected from the group consisting of a synthetic polymer, cellulose, and polysaccharide is preferable. Specifically, gum arabic, gum tragacanth, guar gum, locust bean gum, alginic acid, carrageenan, gelatin, xanthan gum, welan gum, succinoglycan, diutane gum, dextran, methylcellulose, ethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, starch glycolic acid and Salts thereof, propylene glycol alginate, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl methyl ether, polyacrylic acid and salts thereof, carboxyvinyl polymer, polyethylene oxide, copolymer of vinyl acetate and polyvinyl pyrrolidone, cross-linked acrylic acid polymer and Examples thereof include non-crosslinked acrylic acid polymers and salts thereof, styrene acrylic acid copolymers and salts thereof, and the like. That.

  Of these, it is preferable to use polysaccharides. Polysaccharides tend to be less susceptible to fluidity due to vibrations due to their rheological properties, and problems such as poor writing due to ink back are less likely to occur. Xanthan gum is particularly preferable because it is excellent in balance with other properties required for writing instrument inks.

  Lubricants include fatty acid esters of polyhydric alcohols, higher fatty acid esters of sugars, polyoxyalkylene higher fatty acid esters, alkyl phosphate esters, alkyl sulfonates of higher fatty acid amides, alkyl allyl sulfones, which are also used in pigment surface treatment agents. Examples thereof include acid salts, polyalkylene glycol derivatives, fluorine-based surfactants, and polyether-modified silicones. Examples of the rust inhibitor include benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, and saponins. Examples of the antiseptic or antibacterial agent include phenol, sodium omadin, sodium benzoate, and benzimidazole compounds.

  In order to produce this water-based ink composition for writing instruments, a conventionally known method can be employed. For example, in addition to the thermochromic and photochromic microcapsule pigments, a predetermined amount of each component in the water is used. It is obtained by mixing and stirring and mixing with a homomixer or a stirrer such as a disper. Furthermore, if necessary, coarse particles in the ink composition may be removed by filtration or centrifugation.

The viscosity value of the aqueous ink composition for a writing instrument is preferably 500 to 2000 mPa · s at 25 ° C. and a shear rate of 3.83 / s, and 20 to 100 mPa · s at a shear rate of 383 / s. By setting the viscosity within the above range, the ink can be excellent in writability and stability over time. Furthermore, S = αD ⁿ (where 1>n> 0) (S is a shear stress (dyn / cm ² ), D is a shear rate (s ⁻¹ ), α is a non-Newtonian viscosity coefficient) The required non-Newtonian viscosity index n is preferably 0.2 to 0.6. By setting the non-Newtonian viscosity index n in the above range in addition to the above viscosity range, it is possible to appropriately set the fluidity of the ink with respect to vibration and to prevent the occurrence of ink back.

  The surface tension of the aqueous ink composition for writing instruments is preferably 25 to 45 mN / m, more preferably 30 to 40 mN / m. Within this range, the balance between the inside of the pen tip and the ink wettability becomes appropriate, and the occurrence of ink back can be prevented.

  In the refill, an ink follower may be disposed immediately behind the ink. The material constituting the follower can be composed of at least a non-volatile or hardly volatile organic solvent and a thickener. The non-volatile or hardly volatile organic solvent used for the ink follower is used as a base oil for the ink follower, and for example, liquid paraffin is used. Mineral oil and chemically synthesized oil are used as the liquid paraffin, and polybutene, poly α-olefin, ethylene α-olefin oligomer, and the like can be used as the chemically synthesized oil.

  Specific mineral oils that can be used include, for example, commercially available Diana Process Oil NS-100, PW-32, PW-90, NR-68, AH-58 (manufactured by Idemitsu Kosan Co., Ltd.).

  Specific polybutenes that can be used include, for example, the commercially available products Nissan Polybutene 200N, Polybutene 30N, Polybutene 10N, Polybutene 5N, Polybutene 3N, Polybutene 015N, Polybutene 06N, Polybutene 0N (above, manufactured by NOF Corporation), Polybutene HV-15 (made by Nippon Petrochemical Co., Ltd.), 35R (made by Idemitsu Kosan Co., Ltd.), etc. are mentioned.

  Specific poly α-olefins that can be used include, for example, commercially available barrel process oils P-26, P-46, P-56, P-150, P-350, P-1500, P-2200, (P-10000, P-37500) (manufactured by Matsumura Oil Co., Ltd.).

  Specific ethylene α-olefin oligomers that can be used include, for example, commercially available Lucant HC-10, HC-20, HC-100, HC-150, (HC-600, HC-2000). Chemical Co., Ltd.).

  These nonvolatile or hardly volatile organic solvents can be used alone or in combination of two or more.

  Examples of the thickener used for the ink follower include calcium phosphate phosphate, fine particle silica, polystyrene-polyethylene / butylene rubber-polystyrene block copolymer, polystyrene-polyethylene / propylene rubber-polystyrene block copolymer, and hydrogenated styrene. -Butadiene rubber, block copolymer of styrene-ethylenebutylene-olefin crystal, block copolymer of olefin crystal-ethylenebutylene-olefin crystal, acetoalkoxyaluminum dialchelate, and the like can be used, and these can be used alone or in combination.

  As a preferable commercially available calcium salt of phosphate ester that can be used, Crodax DP-301LA (manufactured by Croda Japan Co., Ltd.) and the like can be mentioned. The fine particle silica that can be used includes hydrophilic fine particle silica and hydrophobic fine particle silica. Preferred commercial products of hydrophilic silica include AEROSIL-300, AEROSIL-380 (manufactured by Nippon Aerosil Co., Ltd.), etc. Preferred examples of commercially available hydrophobic silica include AEROSIL-974D, AEROSIL-972 (manufactured by Nippon Aerosil Co., Ltd.) and the like.

  Examples of a commercially available block copolymer of polystyrene-polyethylene / butylene rubber-polystyrene include Kraton GFG-1901X, Kraton GG-1650 (manufactured by Shell Japan), Septon 8007, Septon 8004 (manufactured by Kuraray), and the like. Is mentioned. Furthermore, as a preferable commercial item of the block copolymer of polystyrene-polyethylene / propylene rubber-polystyrene, Kraton GG-1730 (manufactured by Shell Japan Co., Ltd.), Septon 2006, Septon 2063 (manufactured by Kuraray Co., Ltd.) and the like can be mentioned.

  Examples of preferable commercially available hydrogenated styrene-butadiene rubber include DYNARON 1320P, DYNARON 1321P (manufactured by JSR Corporation), Tuftec H1041, Tuftech H141 (manufactured by Asahi Kasei Kogyo Co., Ltd.), and the like.

  DYNARON 4600P (manufactured by JSR) and the like are mentioned as preferred commercial products of the block copolymer of styrene-ethylene butylene-olefin crystals, and DYNARON 6200P and DYNARON 6201B (the preferred commercial products of block copolymers of olefin crystal-ethylene butylene-olefin crystals are JSR) and the like.

  Plenact AL-M (manufactured by Ajinomoto Fine-Techno Co., Ltd.) and the like are preferable as a commercially available product of acetoalkoxy aluminum dial chelate.

  Among these thickeners, from the point of further exerting the effects of the present invention, thermoplastic olefin elastomers such as block copolymers of styrene-ethylenebutylene-olefin crystals and block copolymers of olefin crystals-ethylenebutylene-olefin crystals are used. Use is preferred.

  In the present invention, from the viewpoint of obtaining an ink follower that prevents the occurrence of ink back, the average value of tan δ values measured for each frequency while increasing exponentially in the frequency range of 1 to 63 rad / s is 1.0. The above is preferable, and 1.7 to 3.4 is more preferable.

  Here, tan δ is a value meaning loss elastic modulus / storage elastic modulus, and conventionally, an average value of tan δ values measured for each frequency while increasing exponentially in the frequency region “1 to 63 rad / s”. Has been known to be preferably 1.0 or less. In the present invention, when the average value of the tan δ values measured for each frequency at 1 to 63 rad / s is 1.0 or more, it is possible to absorb vibration and prevent occurrence of ink back.

  Rubber elastic materials such as thermosetting rubber such as silicone rubber, nitrile rubber, ethylene propylene rubber, ethylene propylene diene rubber, and thermoplastic elastomer such as styrene elastomer, olefin elastomer, polyester elastomer, etc. A mixture of two or more rubber elastic materials and a mixture of a rubber elastic material and a synthetic resin can be used. This is a wear test (ASTM D1044) defined in JIS K7204 and a load of 9.8 N, 1000 rpm environment. Below, it comprises so that the Taber abrasion amount in the abrasion wheel CS-17 of a Taber abrasion tester may be 10 mg or more, and a friction body is formed. Furthermore, in order to adjust the Taber abrasion amount to 10 mg or more, alkylsulfonic acid phenyl ester, cyclohexanedicarboxylic acid ester and phthalic acid plasticizer are added to the friction material to give more flexibility. May be. Because the friction body contains alkyl sulfonic acid phenyl ester, cyclohexane dicarboxylic acid ester and phthalic acid plasticizer, the friction body is more easily worn, so that the handwriting is not damaged and the printed characters are not distorted. Can be deleted. Furthermore, the friction body preferably has a durometer D hardness of 30 or more as defined in JIS K6203. Thereby, a predetermined hardness can be ensured and a more stable rubbing operation can be achieved. The friction body can also be applied as a touch pen or a stylus pen.

DESCRIPTION OF SYMBOLS 1 Knock type writing instrument 2 Shaft cylinder 3 Operation part 4 Refill 4a Writing part 5 Spring 10 Braking member

Claims (3)

A shaft cylinder, a writing body arranged in the shaft cylinder, an elastic member that urges the writing body to the rear, and an operation that is pushed forward against the urging force of the elastic member during a knocking operation A knock-type writing instrument comprising:
A knock type writing instrument, wherein a braking portion is provided on an outer surface of the writing body to brake the writing body in cooperation with the shaft cylinder when the writing body is retracted by a knocking operation.   The knock type writing instrument according to claim 1, wherein the braking portion has a protrusion and a contact portion that contacts the protrusion on an inner peripheral surface of the shaft cylinder.   The braking portion is a separate cylindrical member that can be attached to and detached from the writing body, and a plurality of ribs that hold the writing body are formed on an inner peripheral surface of the cylindrical member. The knock type writing instrument according to claim 1 or 2.

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