Toothbrush and toothbrush handle

Abstract

To provide a handle body for toothbrushes without using plastic.SOLUTION: A handle body for toothbrushes comprising a head part having a plurality of bristle holes to be filled with bristle bundles, a neck part extending from the head part, and a handle part extending from the neck part, the handle body is so configured that one or a plurality of bristle hole-forming layers including a plurality of through-holes formed at a head part position, and one or a plurality of bristle hole-non-forming layers including no holes formed at the head part position are superposed, where the head part includes non-penetrating bristle holes, and where the bristle hole-forming layers and the bristle hole-non-forming layers are layers of multilayer paper or derived from the multilayer paper.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a toothbrush and a handle for a toothbrush. [Background technology]

[0002] Known toothbrushes have a bristle bundle made up of multiple bristles attached to the tip of the handle. Commonly available toothbrushes, such as those for general household use, portable toothbrushes, and those used as amenities provided to guests at hotels and inns, generally have a long overall handle, including a head portion where the bristles are attached and a handle portion that extends from the head portion via a neck portion. Furthermore, the head portion is often molded thin to facilitate maneuverability within the oral cavity, and the neck portion is often shaped to be narrower than the head portion to facilitate maneuverability within the oral cavity. Furthermore, toothbrush handles are generally made of hard plastics such as polypropylene polyethylene, polyethylene terephthalate, and polyarylate, in terms of moldability and the strength required for use and for attaching the bristles by flat-wiring (see Patent Documents 1 and 2 below).

[0003] On the other hand, in recent years, marine pollution caused by microplastics has attracted attention, and a move away from plastic is progressing worldwide from the perspective of environmental protection. In Japan, the "Act on Promotion of Resource Recycling Related to Plastics" was enacted, which, for example, requires certain businesses to reduce the use of disposable plastic products. Furthermore, this "Act on Promotion of Resource Recycling Related to Plastics" designates toothbrushes provided to guests by hotels and inns as "specified plastic-containing products," and there is a growing demand for a move away from plastic in toothbrushes.

[0004] Techniques for replacing plastic toothbrush handles and other parts with natural materials such as paper, wood, bamboo, etc. are disclosed in the following Patent Documents 3, 4, and 5. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-16496 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-458 [Patent Document 3] Japanese Patent Application Laid-Open No. 2005-110727 [Patent Document 4] Utility Model Registration No. 3175154 [Patent Document 5] Japanese Patent Application Laid-Open No. 2003-325231 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the technologies described in Patent Documents 3 and 4 are designed to be disposable, have a simple structure in which the brush part is attached to the handle part with adhesive, and do not give sufficient consideration to strength. As a result, the feel of use is significantly different from that of commonly available hard plastic products, and they are not suitable as a substitute for commonly available hard plastic products.

[0007] The technology described in Patent Document 5 increases the strength of the brush body by molding natural plant fibers and paper material made from natural plant fibers in a mold, or by stacking multiple sheets of paper material, resulting in a brush body in the shape of a commonly used hard plastic product. However, simply molding paper material by pressing it in a mold or stacking multiple sheets of paper material is difficult to achieve sufficient strength to be used in the same way as commonly used hard plastic products. It is also difficult to implant bristles by flat-wire braiding, as is the case with conventional commonly used hard plastic products.

[0008] Therefore, the main object of the present invention is to provide a toothbrush handle that does not use plastic and that has the same feel as conventional, commonly available hard plastic products, but can be manufactured simply by flat wire hammering in the same way as commonly available hard plastic products, and a toothbrush having such a handle. [Means for solving the problem]

[0009] The first solution to the above problem is A toothbrush handle body having a head portion having a plurality of bristle implantation holes into which bristle bundles are implanted, a neck portion extending from the head portion, and a handle portion extending from the neck portion, This toothbrush handle is characterized in that one or more tufting hole-forming layers with multiple through holes formed at the head portion and one or more tufting hole-non-forming layers without through holes formed at the head portion are laminated together, so that the head portion has non-through tufting holes, and the tufting hole-forming layer and the tufting hole-non-forming layer are made of multilayer paper or layers derived from multilayer paper.

[0010] The second method is The handle body for a toothbrush according to the first means described above is a handle body for a toothbrush according to the first means, in which the multilayer paper or layers derived from the multilayer paper that constitute the tufted hole-forming layer and the tufted hole-non-forming layer are joined by at least one of an engaging structure that engages the layers with each other by inserting the tip portion of a cut piece formed on a part of the front and back surfaces of the handle body into at least the adjacent layer, and an adhesive.

[0011] The third method is The toothbrush handle according to the first or second aspect contains a siloxane compound.

[0012] The fourth method is The toothbrush has a handle body including a head portion having a plurality of bristle implantation holes into which bristle bundles are implanted, a neck portion extending from the head portion, and a handle portion extending from the neck portion, A toothbrush in which bristle bundles are planted in the bristle planting holes by flat-line driving, The toothbrush handle is One or more tufting hole-forming layers having a plurality of through holes formed at the head portion position and one or more tufting hole-non-forming layers having no through holes formed at the head portion position are laminated together to form a head portion having non-through tufting holes, and the tufting hole-forming layer and the tufting hole-non-forming layer are formed from multilayer paper or a layer derived from multilayer paper. The toothbrush is characterized by the above.

[0013] The fifth method is This toothbrush relates to the fourth means described above, in which the multilayer paper or layers derived from multilayer paper that make up the tufted hole-forming layer and the tufted hole-non-forming layer are joined by at least one of an interlocking structure that engages the layers with each other by inserting the tip portion of a cut piece formed on a part of the front and back surfaces of the handle body into at least the adjacent layer, and an adhesive.

[0014] The sixth method is The toothbrush according to the fourth or fifth aspect of the present invention has a handle containing a siloxane compound.

[0015] The seventh method is The toothbrush according to the fourth or fifth aspect of the present invention is characterized in that the bristle bundle is made of at least one material selected from the group consisting of biomass filaments, natural bristles, and paper yarns. [Effects of the Invention]

[0016] According to the present invention, a plastic-free toothbrush handle is provided which has the same feel as conventional commonly available hard plastic products, and can be manufactured simply by flat wire hammering in the same way as commonly available hard plastic products, and a toothbrush having the handle is also provided. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 2 is a front view of the toothbrush handle according to the embodiment. [Figure 2] 1 is a schematic diagram of a cross section along the longitudinal direction of a handle body for a toothbrush according to an embodiment of the present invention. FIG. [Figure 3]1 is a schematic cross-sectional view illustrating the structure of a toothbrush handle according to an embodiment of the present invention. FIG. [Figure 4] 10A and 10B are diagrams for explaining a locking structure according to the present embodiment. [Figure 5] 1 is a cross-sectional schematic diagram of multilayer paper according to an embodiment of the present invention. [Figure 6] FIG. 2 is an enlarged view of a head portion of a handle for a toothbrush according to the present embodiment. [Figure 7] 1 is a schematic cross-sectional view of a toothbrush according to an embodiment of the present invention. [Figure 8] 1 is a diagram showing a toothbrush according to an embodiment of the present invention; [Figure 9] 10A to 10C are first diagrams illustrating an example of a method for manufacturing a toothbrush handle according to the present embodiment. [Figure 10] FIG. 10 is a second diagram illustrating an example of a method for manufacturing a toothbrush handle according to the present embodiment. [Figure 11] 10A and 10B are diagrams for explaining a method for measuring the bending strength of a toothbrush handle according to the present embodiment. [Figure 12] 10A and 10B are diagrams for explaining the results of measuring the bending strength of the toothbrush handle according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Next, embodiments of the present invention will be described in detail below with reference to Figures 1 to 12. However, the present invention is not limited to these embodiments.

[0019] As shown particularly in Figures 1 and 2, the toothbrush handle 10 of this embodiment is composed of a head portion 11 having a plurality of bristle implantation holes 11H into which bristle bundles 2 are implanted, a neck portion 12 extending from the head portion 11 and narrower than the head portion 11, and a handle portion 13 extending from the neck portion 12 and wider than the neck portion 12, and has an overall thin, elongated shape.

[0020] By implanting bristle bundles 2 into the bristle implantation holes 11H of the toothbrush handle 10, the toothbrush 1 according to this embodiment shown in Figures 7 and 8 is formed. Note that the toothbrush 1 according to this embodiment will also be described together with the embodiment of the toothbrush handle 10, with the same reference numerals assigned to parts corresponding to those in the toothbrush handle 10 of this embodiment.

[0021] As shown in Figures 1 to 3, the toothbrush handle 10 of this embodiment is formed by stacking a tuft hole-forming layer 20 and a tuft hole-free layer 30, which have the same outer edge shape in a plan view, in the thickness direction. Characteristically, these layers 20, 30 are multilayer paper 10M or layers derived from multilayer paper, and the stacking direction of the tuft hole-forming layer 20 and the tuft hole-free layer 30 coincides with the stacking direction of the paper layers in the multilayer paper 10M or layers derived from multilayer paper. The multilayer paper-derived layer is a layer whose precursor is the multilayer paper 10M, and is, for example, a layer that has undergone appropriate processing to further enhance the strength of the multilayer paper 10M. More specifically, examples of such a layer include a layer formed by pressing the multilayer paper 10M, a layer formed by compressing the multilayer paper 10M in the thickness direction, a layer formed by heat-treating the multilayer paper 10M, a layer formed by applying a coating agent to the multilayer paper 10M to enhance its strength, and a layer containing an additive that enhances the strength of the multilayer paper 10M. Furthermore, the multilayer paper 10M may be a layer that has undergone multiple treatments, such as a layer that has been impregnated with an additive and then compressed or heat-treated. Hereinafter, when describing matters common to the multilayer paper 10M that constitutes the flocked hole-forming layer 20 and the flocked hole-free layer 30 and the multilayer paper 10M that serves as a precursor to layers derived from the multilayer paper, no distinction will be made and the term "multilayer paper 10M" will be used. The multilayer paper 10M may be commercially available, such as Elipla Paper manufactured by Dainichi Paper Co., Ltd. The pressing pressure used to compress the multilayer paper 10M in the thickness direction and the heating temperature used to heat-treat the multilayer paper 10M are not necessarily limited.

[0022] The toothbrush handle 10 of this embodiment is not made of plastic, but is constructed of at least one of the multilayer paper 10M and layers derived from multilayer paper, as described above, which is paper. This allows for a plastic-free design. While a single-layer paper material is difficult to achieve the same strength as a plastic material, the multilayer paper 10M, which is constructed of multiple paper layers 60, 51, provides sufficient strength. Because the toothbrush handle 10 of this embodiment is constructed of the multilayer paper 10M or layers derived from multilayer paper, it achieves a thin, elongated overall shape with the head portion 11 and handle portion 13 connected via a narrow neck portion 12, similar to commonly used hard plastic products, while still providing sufficient strength and a user experience similar to that of commonly used hard plastic products. Furthermore, because the multilayer paper is an aggregate of pulp fibers, it will not shatter in the mouth when chewed with teeth, making it sufficiently safe to use.

[0023] Here, the strength of the toothbrush handle 10 and toothbrush 1 of this embodiment is not necessarily limited, but the bending strength in a three-point bending load test using the secant line method in accordance with JIS K 7171 is preferably 15 N or more at a bending deflection of 1 mm and 30 N or more at a bending deflection of 2 mm. In this three-point bending test, as shown in FIG. 11 , the positions of the support bases 80A and 80B are two points sandwiching the neck portion 12, and the distance L15 between the two points is 70 mm. Furthermore, one support base 80A is located at the head portion 11 (preferably at a position where the distance L16 from the tip is 15 mm), and the other support base 80B is preferably located at the handle portion 13. Measurements are performed with a load cell capacity of 1 kN, a pressing speed of 10 mm / min, a radius R1 of the indenter 81 of 5 mm, and a radius R2 of the tip of each support base of 2 mm. The measurement sample is set with the flocked part facing upwards, and the pushing position is 75 mm from the tip (L17), at a position closer to the handle than the center between the support stands. With the above bending strength, it is easy to obtain a feel similar to that of a general-purpose hard plastic product.

[0024] On the other hand, the toothbrush handle 10 and toothbrush 1 of this embodiment preferably have water resistance of at least 3 minutes, more preferably at least 5 minutes, although this is not necessarily limited to these. Here, water resistance means that the individual layers do not separate or hydrolyze even when completely immersed in water. However, it is particularly desirable that the bending strength in the three-point bending load test according to JIS K 7171 be maintained even after immersion for 5 minutes.

[0025] On the other hand, the toothbrush handle 10 of this embodiment is characterized by the fact that it comprises a tufting hole-formed layer 20, which has multiple through-holes 21H formed at the head portion 21, and a tufting hole-free layer 30, which does not have through-holes at the head portion, stacked together to form non-through-hole tufting holes 11H in the head portion 11. In other words, the tufting holes 11H formed in the head portion 11 have bottoms, which are made of high-strength multilayer paper 10M or a multilayer paper-derived layer, the non-tufting hole-formed layer 30. Therefore, the toothbrush handle 10 of this embodiment can be implanted using the flat wire punching technique used in conventional, commonly available hard plastic toothbrushes. In other words, the multilayer paper 10M and the multilayer paper-derived layer are a type of paper that is an aggregate of fibers, providing excellent micro-deformability, and the layered structure of multiple paper layers provides excellent Z-axis strength. Therefore, if the head portion 11 has a structure in which layers of multilayer paper or layers derived from multilayer paper are stacked, when the flat wire is driven in, the flat wire will firmly bite into the fibers, there is little risk of the head portion cracking, and there is also little risk of the flat wire penetrating the bottom of the hair implantation hole 11H, making it easier to implant hair using the flat wire.

[0026] Furthermore, it is desirable to incorporate a siloxane compound into the tufting hole-forming layer 20 and the tufting hole-free layer 30 of the toothbrush handle 10 of this embodiment, particularly to facilitate bristles implantation by the flat wire punching method and to increase the rigidity and strength of the entire handle. The inclusion of a siloxane compound results in a multilayer paper-derived layer with increased strength and water resistance due to siloxane bonds. In particular, incorporating a siloxane compound in the tufting hole-free layer 30, including the portion of the tufting hole-forming layer 20 that overlaps the through-holes 21H (head portion position), effectively prevents a decrease in strength due to water accumulating in the tufting holes 11H during toothbrushing. The siloxane compound may simply be coated as a surface coating on the outer surface of the toothbrush handle 10. More preferably, the siloxane compound penetrates to a certain depth from the outer surface of the handle 10, bonding to the pulp and cellulose fibers that make up the multilayer paper and layers derived from the multilayer paper, or coating the pulp and cellulose fibers. This further increases the stiffness and strength of the entire handle.

[0027] The siloxane compound is not necessarily limited as long as it has a siloxane bond, but since the toothbrush is inserted into the oral cavity, it is desirable that the siloxane compound be non-toxic or low-toxic to living organisms. Furthermore, the siloxane compound can be incorporated into the handle 10 by coating, impregnating, or dipping the toothbrush 1 or the handle 10 with the siloxane compound. Alternatively, the multilayer paper 10M can be coated, impregnated, or otherwise impregnated with an appropriate alkoxysilane solution or an alkoxysilane solution-processed product, followed by heating, heating, and further compression. In this way, the siloxane compound is incorporated into the multilayer paper by bonding to the pulp fibers or cellulose fibers that make up the layers of the multilayer paper, or by coating the pulp fibers or cellulose fibers.

[0028] On the other hand, the toothbrush 1 and handle 10 according to the present embodiment may contain at least one of an antibacterial agent and an antiviral agent. Other known functional auxiliaries may also be added as long as they do not impair the effects of the present invention. The antibacterial and antiviral agents are not limited, and any known agent suitable for toothbrush applications can be used. In particular, the toothbrush 1 and handle 10 according to the present embodiment are composed of multilayer paper 10M, which is paper made from pulp fibers, or layers derived from multilayer paper. Therefore, unlike plastic products, there is no need to incorporate antibacterial agents into the resin material. Instead, antibacterial and antiviral agents can be easily applied by coating, coating, impregnation, or dipping. The antibacterial and antiviral agents can be applied together with the siloxane compound. Furthermore, the siloxane compound itself may have antiviral and antibacterial properties.

[0029] The tufted hole-forming layer 20 and the tufted hole-free layer 30 do not necessarily have to be single layers, but can be multiple layers. The illustrated configuration shows two tufted hole-forming layers 20 and one tufted hole-free layer 30. However, this laminated structure is not limited to this. The handle body 10 according to this embodiment may also include other layers as long as they do not impair the effects of the present invention. For example, an adhesive layer may be provided to bond the layers together. This adhesive must be able to eliminate plastics, and it is preferable to use an adhesive made of a natural material or a natural-material-derived adhesive. Furthermore, a layer of a material other than plastic may be laminated to increase the thickness of the handle portion 13 for easier gripping. Of course, this layer may be made of the same material as the multilayer paper 10M used to form the tufted hole-forming layer 20 and the tufted hole-free layer 30.

[0030] The multilayer paper 10M and layers derived from the multilayer paper that make up the pore-forming layer 20 and the pore-free layer 30 are not necessarily limited, but it is desirable that they be arranged so that the longitudinal direction from the head portion 11 to the handle portion 13 coincides with the machine direction (MD) of the paper. By aligning the machine direction (MD) of the paper with the machine direction, the toothbrush becomes less likely to break and more flexible.

[0031] The method for joining the layers constituting the pore-forming layer 20 and the pore-free layer 30 together is not necessarily limited. As long as the effects of the present invention are not impaired, joining can be achieved by adhesives, crimping, swaging, eyelets, wedging, stapling, or a fastening structure also known as a coreless staple. Multiple joining methods may also be used in combination. Adhesives that can be used for joining include starch, various modified starches, modified celluloses such as carboxymethyl cellulose, water-soluble polymer adhesives such as polyvinyl alcohol, and aqueous emulsion resins such as acrylic esters and vinyl acetate. Starch and cellulose-based natural materials are preferred in terms of environmental impact. Rivets and staples that form the swaging and eyelets used for joining should preferably be made of wood or metal, rather than plastic. One preferred joining method is a locking structure, as shown in FIG. 4(A) and FIG. 4(B), which shows a cross section (BB) of the handle body 10. Cut-out pieces 70, 70 are formed on portions of the front and back surfaces by punching or other methods, and their tip portions 70t, 70t are pressed into at least the adjacent layer, mechanically joining the layers together. In this locking structure, a half-cut line may be formed at the same position in plan view as the edge 70e of the cut-out piece 70 in at least the adjacent layer to facilitate insertion of the tip portion 70t. The toothbrush handle body 10 and toothbrush 1 of this embodiment are made of multilayer paper 10M or a layer derived from multilayer paper, and are made of a stiff paper material, so the layers can be joined together using this locking structure. This locking structure is advantageous because it joins the tufted hole-forming layer 20 and the tufted hole-non-forming layer 30 by partial engagement, eliminating the need for additional components. However, as mentioned above, a mechanical locking structure, including this locking structure, may be used in combination with an adhesive. This also has the advantage of reducing the amount of adhesive used. Another locking structure, not shown, may be a pressure-bonding structure in which pressure is applied to a portion of the handle from the front and back sides in the thickness direction, causing the pressed portion to bite into at least the adjacent layer, thereby locking the pressed portion.

[0032] Here, the multilayer paper 10M constituting the implanted hole-forming layer 20 and the implanted hole-non-forming layer 30, and the multilayer paper 10M serving as a precursor for the layer derived from the multilayer paper, have a basis weight of 700 g / m 2 More preferably, 850 g / m 2 More preferably, 950 g / m 2 That's all. Multilayer paper 10M in this range is likely to have sufficient stiffness. Furthermore, multilayer paper of this basis weight is likely to have sufficient stiffness and strength, and is likely to have a similar feel to commonly available products made of harder plastic. There is no upper limit to the basis weight of multilayer paper 10M, but there is a risk that creases may easily occur when using calender rolls during papermaking, and from this point of view, the upper limit is set at 1470 g / m 2 is preferred, and 1240 g / m 2 The paper thickness is preferably 900 μm or more and 1,500 μm or less, and more preferably 1,000 μm or more and 1,350 μm or less. The basis weight is a value measured in accordance with "Paper and paperboard - Basis weight measurement method" described in JIS P 8124 (2011), and the paper thickness is a value measured in accordance with "Paper and paperboard - Thickness and density test method" described in JIS-P8118 (2014).

[0033] The multilayer paper 10M that forms the pore-forming layer 20 and the pore-non-forming layer 30, and the multilayer paper 10M that serves as a precursor to the multilayer paper-derived layers, are preferably made of only natural fibers, without synthetic fibers including plastics. Preferably, the multilayer paper is made of only pulp fibers.

[0034] Preferred constituent pulp fibers are softwood kraft pulps such as unbleached softwood kraft pulp (NUKP), semi-bleached softwood kraft pulp (NSBKP), and bleached softwood kraft pulp (NBKP), and hardwood kraft pulps such as unbleached hardwood kraft pulp (LUKP), semi-bleached hardwood kraft pulp (LSBKP), and bleached hardwood kraft pulp (LBKP). Bleached softwood kraft pulp and bleached hardwood kraft pulp are particularly preferred because they facilitate compatibility between the appearance and strength of the processed product. Other pulps may include chemical pulps such as recycled paper pulp, hardwood sulfite pulp, and softwood sulfite pulp, as well as pulps produced chemically or mechanically from non-wood fibers such as kenaf, hemp, and reed, and various other known pulps may be used in appropriate combination.

[0035] The multilayer paper 10M that constitutes the pore-forming layer 20 and the pore-non-forming layer 30, and the multilayer paper 10M that serves as a precursor to layers derived from the multilayer paper, preferably have a tensile strength of 50 kN / m or more in both the longitudinal and transverse directions measured in accordance with JIS P 8113 (2006). If the multilayer paper has this tensile strength, it is easy to ensure the strength required for a toothbrush.

[0036] It is also desirable to add at least one of a sizing agent and a paper strength agent as a papermaking additive to the multilayer paper 10M that constitutes the hole-forming layer 20 and the hole-non-forming layer 30, and to the multilayer paper 10M that serves as a precursor to layers derived from the multilayer paper. This makes it easier to adjust the strength to the desired level.

[0037] Examples of sizing agents include styrene-based sizing agents, alkyl ketene dimer (AKD), alkenyl succinic anhydride (ASA), neutral rosin sizing agents, rosin sizing agents, and modified rosin emulsion sizing agents. Among these, rosin sizing agents and modified rosin emulsion sizing agents are preferred. The rosin sizing agent is not particularly limited. Examples of rosin-based substances include fortified rosins obtained by modifying rosins such as gum rosin, wood rosin, and tall oil rosin with α,β-unsaturated carboxylic acids or their anhydrides, such as fumaric acid, maleic acid, and acrylic acid, and rosin esters obtained by reacting rosins with polyhydric alcohols, such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and diglycerin. Rosin sizing agents also include emulsions of these substances alone or a mixture thereof, as well as emulsions of these substances emulsified alone and then mixed together. Furthermore, emulsions to which various polymers have been added to further improve sizing properties are also included.

[0038] Various known paper strength agents can be used, such as polyacrylamide resins, polyamide resins, polyamine resins, acrylic resins, melamine resins, urea resins, and polyamide-epichlorohydrin resins. Among these, it is preferable to use amphoteric paper strength agents. Examples of amphoteric polyacrylamides include copolymers of acrylamide with anionic monomers and cationic monomers, Mannich-modified copolymers of acrylamide with anionic monomers, and Hoffman degradation products. Amphoteric polyacrylamides, in particular, have a self-fixing function, so even if they are added in excess to improve inter-paper strength, they do not result in an excess of cations. Therefore, when used together with a modified rosin emulsion sizing agent, they can stably fix the sizing agent.

[0039] The amount of sizing agent added is preferably 0.5 kg / t or more and 5.0 kg / t or less in terms of solids. The amount of paper strength agent added is preferably 12 kg / t or more and 30 kg / t or less in terms of solids. Note that "kg / t" indicates the mass (kg) per ton of pulp. By adding sizing agent in this range, water resistance can be improved, making the pulp suitable for toothbrush applications.

[0040] The multilayer paper 10M may contain various other additives as long as they do not impair the intended effect of the present invention. For example, polyvinyl alcohol, wax, etc. may be applied.

[0041] As shown in the cross-sectional schematic diagram of Figure 5, it is particularly desirable for the multilayer paper 10M to have surface layers 51, 51 and a middle layer 60. While it is difficult to increase the strength of a single-layer paper material compared to plastic materials, the multilayer paper 10M can easily achieve the same strength. Furthermore, the properties of each layer of the multilayer paper 10M can be varied, making it easy to maintain high density while maintaining elasticity and water resistance. For example, combining a pair of surface layers 51, which are water-resistant but stiff and prone to breaking, with a flexible middle layer 60 can achieve excellent water resistance, toughness, and durability. This improves the overall water resistance of the toothbrush, and also facilitates the flexible handle, particularly the neck portion, providing a user experience similar to that of commonly available hard plastic toothbrushes. Multilayer paper can be manufactured by multi-layer papermaking. These characteristics of the multilayer paper 10M are not lost even when the layers are compressed in the thickness direction by, for example, pressing.

[0042] The number of layers of the multilayer paper 10M is not limited, but is preferably five to nine, with three or more middle layers 60, particularly five. In particular, the form shown in Figure 5 has three middle layers 60. Having a total of three or more middle layers 60 can further improve the toughness and durability of the multilayer paper. From the perspective of maintaining interlayer strength, the upper limit of the total number of middle layers 60 is preferably seven or less. Furthermore, three to seven layers makes it easier to operate a cylinder-type multi-cylinder papermaking machine while maintaining interlayer strength.

[0043] The basis weight of the surface layer 51 and the middle layer 60 in the multi-layer paper 10M is not particularly limited, but the basis weight of the surface layer 51 is 50.0 g / m per layer. 2 More than 200.0g / m 2 The basis weight of the entire middle layer is preferably 400 g / m or less. 2 More than 950g / m 2 It is preferable that the ratio of the total basis weight of the pair of surface layers 51, 51 to the basis weight of the entire multilayer paper is 20.0% or more and 35.0% or less. The pair of surface layers have high rigidity, and the middle layer has excellent flexibility. Furthermore, by setting the ratio of the total basis weight of the pair of surface layers in the above range, the multilayer paper can be given a property of being difficult to bend. The density is 0.65 to 1.00 g / cm 3 , especially 0.73 to 0.85 g / cm 3 When the density of the multilayer paper is in this range, the paper has a high basis weight, excellent rigidity, and is difficult to break.

[0044] Furthermore, it is preferable that at least one of the above-mentioned sizing agents and paper strength agents be added as papermaking additives to each of the surface layers 51, 51 and the middle layer 60 of the multilayer paper 10M. In this case, the amount of sizing agent added to the surface layer 51 is preferably 0.5 kg / t or more and 5.0 kg / t or less in terms of solids. The amount of sizing agent added to the middle layer 60 is preferably 2.0 kg / t or more and 5.0 kg / t or less in terms of solids. The amount of paper strength agent added to each layer is preferably 12 kg / t or more and 30 kg / t or less in terms of solids. By setting the amount within this range, it is easy to impart various paper strengths, such as interlaminar strength, to the multilayer paper.

[0045] Furthermore, it is desirable that the pulp fibers constituting each layer of the multilayer paper 10M, in the surface layer 51 and middle layer 60, be a mixture of softwood kraft pulp and hardwood kraft pulp. This increases the paper thickness and ensures sufficient strength. Furthermore, by setting the mass ratio (%) of softwood kraft pulp to hardwood kraft pulp in the surface layer to between 5 / 95 and 20 / 80, a large amount of hardwood kraft pulp, which is rigid and easily densified, is contained, giving the surface layer high density and rigid characteristics, and making it more likely to have excellent strength. In addition to the surface layer, it is desirable that the mass ratio (%) of softwood kraft pulp to hardwood kraft pulp in the middle layer be between 20 / 80 and 40 / 60. In particular, by adding 5% or more more softwood kraft pulp, which is more flexible than the surface layer, the paper will have better flexibility.

[0046] Furthermore, the multilayer paper 10M has a Taber stiffness measured in accordance with JIS P 8125 (2000) of 125 mN·m or more, preferably 150 mN·m or more, in the machine direction, and 40 mN·m or more, preferably 60 mN·m or more, in the cross direction. This multilayer paper 10M has sufficient stiffness and strength, and is likely to have a feel similar to that of commonly available hard plastic products.

[0047] Furthermore, the multi-layer paper 10M has a Z-axis strength of 400kN / m, measured in accordance with JAPAN TAPPI Paper and Pulp Test Method No. 18-1:2000. 2 More than 450kN / m 2 The above is desirable. The implantation hole-forming layer, the through-holes in the implantation hole-forming layer, and the implantation hole-non-forming layer can be easily produced by punching using a Thomson process or by cutting using a cutting plotter or the like.

[0048] The size and specific dimensions of the toothbrush handle 10 and toothbrush 1 of this embodiment are not limited. However, as shown in Figures 1 and 2, the overall length L1 can be 150-190 mm, the width L3 of the head portion 11 can be 9.5-15.0 mm, the thickness L4 of the head portion handle can be 3.0-6.0 mm, the length L5 of the head portion 11 can be 20.0-30.0 mm, the width L6 of the handle portion 13 can be 10.5-14.5 mm, the length L7 of the neck portion 12 can be 30-40 mm, and the width L8 of the neck portion 12 can be 4-8 mm. This shape results in a thin, elongated shape in which the head portion 11 and the handle portion 13 are connected via a narrow neck portion 12, similar to commonly used hard plastic products, and provides a similar feel to commonly used hard plastic products. Furthermore, the multilayer paper or multilayer paper-derived layers described above can easily ensure sufficient strength and water resistance.

[0049] Furthermore, the toothbrush handle 10 of this embodiment can be made into a toothbrush 1 by attaching bristle bundles, each of which is made by bundling multiple filaments and folding them in half, to each bristle hole 11H using a known method using a flat wire. The thickness of the flat wire and the amount of the flat wire that fits into the bristle hole can be designed appropriately. As shown in FIG. 6 , the diameter L9 of the through-holes 21H in the bristle hole-forming layer 20 and the bristle holes 11H formed thereby in the head portion 11 is not limited, but is approximately 1.2 to 2.4 mm, preferably 1.3 to 1.9 mm. The number and arrangement of the bristle holes 11H in the head portion 11 are not necessarily limited. However, the distance L10 from the outer edge of the head portion 11 to the bristle holes 11H is not limited, but is preferably 0.7 to 1.9 mm. The spacing L11 between the bristle holes is also not limited, but is preferably 0.7 to 1.9 mm. With this distance and spacing, cracks caused by driving in the flat wire are unlikely to occur, and the feel of use can be similar to that of a general-purpose product.

[0050] The filaments of the bristle bundles 2 implanted in the implantation holes 11H and constituting part of the toothbrush are not limited. They may be artificial bristles made of resin materials such as nylon, polyester, or polyolefin. However, from the perspective of eliminating plastics, filaments derived from natural materials are preferred, such as biomass filaments derived from castor oil extracted from castor beans, natural bristles such as pig bristles or horse bristles, or paper yarn made from natural fibers such as Manila hemp. When artificial bristles are implanted, lines, perforations, half slits, or the like may be provided at appropriate positions on the neck, as long as they do not reduce the strength of the toothbrush, to make it easier to separate the head from the other parts and allow the head to be disposed of separately.

[0051] The toothbrush of this embodiment can be manufactured by any method, but preferably as follows. First, as shown in FIG. 9, multiple sheets of multilayer paper 10m, 10m that will become the tuft hole-forming layer 20 are laminated together so that the depth of the tuft hole 11H is ensured. Then, only the portions that will become the tuft hole 11H are punched out to form the through-holes 21H. This lamination can be performed by pressing or gluing. Next, as shown in FIG. 10, another multilayer paper 10s that will become the tuft hole-non-forming layer 30 is laminated on one side of the laminated multilayer paper 10m, 10m that will become the laminated tuft hole-forming layer 20, and the two are further laminated together. This lamination can be performed by pressing or gluing. Next, the outer edge of the toothbrush handle 10 is punched out to form individual handles 10. Note that, prior to or after this punching, a process for incorporating a siloxane compound, for example, can be performed. Furthermore, press processing can be performed simultaneously with punching. Next, once the individual handles are obtained, bristles are implanted into the implantation holes using the known flat wire implantation method to form individual toothbrushes. This manufacturing method allows multiple handles 10 to be produced from a single sheet of multilayer paper 10m, 10m, 10s, and enables industrial and stable production. [Example]

[0052] Next, the bending strength of the toothbrushes according to the present invention (Examples 1 and 2) was measured and compared with that of conventional plastic toothbrushes (Comparative Examples 1 and 2).

[0053] The test method was a three-point bending load test using the secant method in accordance with JIS K 7171. As shown in Figure 11, support bases 80A and 80B were positioned at two points sandwiching the neck portion 12, with the distance L15 between the two points being 70 mm. One support base 80A was positioned at the head portion 11, with a distance L16 from the tip being 15 mm. The load cell capacity was 1 kN, the indentation speed was 10 mm / min, the radius R1 of the indenter 81 was 5 mm, and the radius of the tip of each support base was R2 = 2 mm. The measurement sample was set with the flocked portion facing upward, and the indentation position was a distance L17 of 75 mm from the tip.

[0054] The handle body of Example 1 had a three-layer structure consisting of one tufted hole-forming layer and two tufted hole-free layers, and each layer was bonded with a polyvinyl alcohol adhesive. The bristle bundles were implanted by flat-line stitching. Each layer was made of multi-layer paper with a basis weight of 1000 g / m² containing a siloxane compound. The multi-layer paper used had a surface layer with a basis weight of 140 g / m² and a middle layer with a total basis weight of 720 g / m² (a total of three layers). Example 2 used the toothbrush of Example 1 that had been immersed in water for five minutes. Comparative Example 1 was a commercially available plastic toothbrush for general household use, and Comparative Example 2 was a commercial plastic toothbrush distributed at accommodation facilities.

[0055] The results of the bending strength test are shown in Figure 12. As shown in Figure 12, it can be confirmed that the toothbrush according to the present invention, although made of multilayer paper, is able to maintain the same bending strength as a plastic toothbrush even after being immersed in water for 5 minutes. Furthermore, no decrease in strength was observed despite the bristle bundles being planted using flat wire braiding.

[0056] Therefore, according to the present invention, a plastic-free toothbrush handle is provided that has the same feel as commonly available hard plastic products, and can be manufactured simply and with the same flat wire hammering method as commonly available hard plastic products, as well as a toothbrush having such a handle. [Explanation of symbols]

[0057] 1...toothbrush, 2...bristle bundle, 10...handle body, 10M, 10m, 10s...multilayer paper, 11...head portion, 11H...tufting hole, 12...neck portion, 13...handle portion, 20...tufting hole forming layer, 21...head portion position, 21H...through hole, 30...tufting hole non-forming layer, 51...surface layer, 60...middle layer, 80A, 80B...support base, 81...indenter, L1...total length of toothbrush and toothbrush handle body, L2...thickness of toothbrush handle body L3...width of head, L4...thickness of head, L5...length of head, L6...width of handle, L7...length of neck, L8...width of neck, L9...diameter of tufting hole (through hole), L10...distance from outer edge of head to tufting hole, L11...spacing between tufting holes (between through holes), L15...distance between support bases, L16...distance from tip to support base, L17...distance from tip to pushing position.

Claims

1. A toothbrush handle body having a head portion having a plurality of bristle implantation holes into which bristle bundles are implanted, a neck portion extending from the head portion, and a handle portion extending from the neck portion, One or more tufting hole-forming layers having a plurality of through holes formed at the head portion position and one or more tufting hole-free layers having no through holes formed at the head portion position are laminated together, so that the head portion has non-through tufting holes, and the tufting hole-forming layer and the tufting hole-free layer are multilayer paper in which a plurality of paper layers are laminated or layers derived from the multilayer paper. A toothbrush handle characterized by:

2. A handle body for a toothbrush as described in claim 1, wherein the multilayer paper or layers derived from the multilayer paper, which are made up of multiple stacked paper layers and which constitute the tufted hole-forming layer and the tufted hole-non-forming layer, are joined by at least one of an interlocking structure that engages the layers with each other by inserting the tip portion of a cut-out piece formed on a part of the front and back surfaces of the handle body into at least the adjacent layer, and an adhesive.

3. 3. The toothbrush handle according to claim 1, which contains a siloxane compound.

4. The toothbrush has a handle body including a head portion having a plurality of bristle implantation holes into which bristle bundles are implanted, a neck portion extending from the head portion, and a handle portion extending from the neck portion, A toothbrush in which bristle bundles are planted in the bristle planting holes by flat-line driving, The toothbrush handle is One or more tufting hole-forming layers having a plurality of through holes formed at the head portion position and one or more tufting hole-free layers having no through holes formed at the head portion position are laminated together, so that the head portion has non-through tufting holes, and the tufting hole-forming layer and the tufting hole-free layer are multilayer paper in which a plurality of paper layers are laminated or layers derived from the multilayer paper. A toothbrush characterized by:

5. The toothbrush of claim 4, wherein the multilayer paper or layers derived from the multilayer paper, which are made up of a plurality of stacked paper layers and which constitute the tufted hole-forming layer and the tufted hole-non-forming layer, are joined by at least one of an interlocking structure that interlocks the layers with each other by inserting the tip portion of a cut-out piece formed on a portion of the front and back surfaces of the handle body into at least the adjacent layer, and an adhesive.

6. 6. The toothbrush according to claim 4, wherein the handle contains a siloxane compound.

7. The toothbrush according to any one of claims 4 to 6, wherein the bristle bundle is made by bundling at least one selected from the group consisting of biomass filaments, natural bristles, and paper yarns.

Images