JP2010241097A - Ink tube for inkjet printer and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink tube for an inkjet printer which is excellent in workability and without eluting a zinc compound into ink. <P>SOLUTION: In the ink tube for the inkjet printer, a rubber component including a butyl rubber, an olefinic resin including polypropylene, a thermoplastic elastomer including a styrenic thermoplastic elastomer, and a cross-linking agent comprising a triazine derivative are blended. On the other hand, the zinc compound is not blended. The ink tube for the inkjet printer is molded from a thermoplastic elastomer composition in which the rubber component is dynamically cross-linked by the cross-linking agent and dispersed in a matrix comprising the olefinic resin and the thermoplastic elastomer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ink tube for an ink jet printer and a manufacturing method thereof.

  Since an ink tube for an ink jet printer is required to be flexible, it is conventionally formed of a rubber material. As the rubber material, general cross-linked rubber, thermoplastic elastomer, or thermoplastic elastomer obtained by dynamic cross-linking is used, but each has a problem.

  A general cross-linked rubber requires a cross-linking step in order to exhibit rubber elasticity. The crosslinking step is usually aimed at crosslinking double bonds contained in the rubber polymer, and a crosslinking agent is added for this purpose. As the crosslinking agent, sulfur or thiuram compounds have been used for a long time. Since these crosslinking agents cannot obtain a sufficient crosslinking density, a crosslinking accelerator composed of a zinc compound is usually blended. However, when an ink tube is formed using a composition containing a zinc compound, the zinc compound may be eluted into the ink. In addition, it is difficult to extrude the composition into an ink tube with a general crosslinked rubber, and there is a problem that a molding cost is required because a crosslinking step is required.

In addition to crosslinking with sulfur or the like, examples of the usual rubber crosslinking method include peroxide crosslinking, metal crosslinking, and resin crosslinking.
Among these, the peroxide crosslinking has a problem that the polymer is easily decomposed by the peroxide, and is noticeably generated when a butyl rubber is used as a rubber component. Since both metal crosslinking and resin crosslinking require a metal salt as a crosslinking aid, there are the same problems as the above sulfur crosslinking.

Under such circumstances, an ink tube using a thermoplastic elastomer (TPE) has been proposed. Since the thermoplastic elastomer (TPE) does not require crosslinking, it is not necessary to add a heavy metal derived from the crosslinking agent, crosslinking accelerator or crosslinking aid.
Moreover, since the molding method similar to a thermoplastic resin can be used, it is preferable also from a viewpoint of moldability. That is, since there is little or no finishing process (for example, deburring, punching, etc.) of the molded product after crosslinking necessary for the crosslinked rubber in the thermoplastic elastomer (TPE), it is easy to obtain an economic advantage at the time of molding.

  However, a thermoplastic elastomer (TPE) has a problem that it is inferior in heat resistance because it does not have a chemical crosslinking point. In particular, the value of compression set at high temperatures is large, and in this respect, it is significantly inferior to crosslinked rubber. In recent years, with the downsizing of inkjet printers, the operating temperature of ink tubes has risen, and the thermoplastic elastomer, which has a large compression set and easily loses its shape under the usage environment, is a problem as an ink tube material for inkjet printers. Have

Thermoplastic elastomers (TPE) include thermoplastic elastomers (TPV) that perform dynamic crosslinking, and the present applicant provides an ink tube made of the thermoplastic elastomer in Japanese Patent Application Laid-Open No. 2005-138506.
The thermoplastic elastomer (TPV) that performs the dynamic crosslinking means a composite in which a rubber component is crosslinked and finely dispersed in a thermoplastic resin, or a composition similar thereto.
A thermoplastic elastomer (TPV) that performs this type of dynamic crosslinking has a chemical crosslinking point, so compression set at a higher temperature is lower than that of a thermoplastic elastomer (TPE) that does not have the above chemical crosslinking point. Small and excellent in heat resistance. Furthermore, since it is thermoplastic, productivity is better than general crosslinked rubber.

However, the thermoplastic elastomer (TPV) that performs the dynamic cross-linking requires a cross-linking agent and a cross-linking aid in order to perform cross-linking, and thus causes the same problem as the above-described ordinary cross-linked rubber.
In general, a thermoplastic elastomer (TPV) that undergoes dynamic cross-linking preferably uses a peroxide cross-linking agent or a resin cross-linking agent because the physical properties of the cross-linked product are excellent. However, peroxide crosslinkers can cause degradation of the polymer components. Moreover, in the resin crosslinking agent, if a zinc compound is not used as a crosslinking aid, the crosslinking reaction becomes insufficient. However, if the zinc compound is used, the above problem occurs, so there is room for improvement.

JP 2005-138506 A

  In view of the above problems, an object of the present invention is to provide an ink tube for an ink jet printer made of a thermoplastic elastomer (TPV) that can sufficiently perform dynamic crosslinking of a rubber component even under a condition not containing a zinc compound. .

In order to solve the above-mentioned problems, the present invention contains a rubber component containing a butyl rubber, an olefin resin containing polypropylene, a thermoplastic elastomer containing a styrene thermoplastic elastomer, and a crosslinking agent comprising a triazine derivative. On the other hand, no zinc compound is blended,
Provided is an ink tube for an ink jet printer, which is formed from a thermoplastic elastomer composition in which the rubber component is dynamically cross-linked and dispersed by the cross-linking agent in a matrix comprising the olefin resin and the thermoplastic elastomer. ing.

  The present inventors have conducted trial and error studies on a crosslinking agent that can sufficiently perform dynamic crosslinking of a rubber component even in the absence of a zinc compound as a crosslinking aid, and as a result, a triazine derivative has been used as a crosslinking agent. The present invention has been completed through further studies and knowledge. That is, the present invention is characterized in that by using a triazine derivative as a crosslinking agent, a rubber component is dynamically crosslinked in a matrix composed of an olefin resin and a styrene thermoplastic elastomer in the absence of a zinc compound. And

  As described above, when a rubber component is dynamically cross-linked using a triazine derivative as a cross-linking agent, the rubber component can be finely dispersed in a matrix containing polypropylene and a styrene-based thermoplastic elastomer, and the adhesion of the surface of the ink tube that becomes a molded product can be achieved. Can improve sex. This effect is conspicuous when an isobutylene-isoprene copolymer rubber, which will be described later, is used as the rubber component. And since this effect is not influenced by the kind of thermoplastic resin, a workable and cheap polypropylene can be used as a thermoplastic resin.

（式中、Ｒは、−ＳＨ、−ＯＲ¹、−ＳＲ²、−ＮＨＲ³または−ＮＲ⁴Ｒ⁵（Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴およびＲ⁵は、アルキル基、アルケニル基、アリール基、アラルキル基、アルキルアリール基またはシクロアルキル基を示す。Ｒ⁴およびＲ⁵は同一であっても異なっていてもよい。）であり、Ｍ¹およびＭ²は、同一または異なって、Ｈ、Ｎａ、Ｌｉ、Ｋ、１／２Ｍｇ、１／２Ｂａ、１／２Ｃａ、脂肪族１級、２級もしくは３級アミン、第４級アンモニウム塩またはホスホニウム塩である。）で表される化合物が挙げられる。 Examples of the triazine derivative used in the present invention include the following general formula (I);

(In the formula, R is —SH, —OR ¹ , —SR ² , —NHR ³ or —NR ⁴ R ⁵ (R ¹ , R ² , R ³ , R ⁴ and R ⁵ are alkyl groups, alkenyl groups, An aryl group, an aralkyl group, an alkylaryl group or a cycloalkyl group, wherein R ⁴ and R ⁵ may be the same or different, and M ¹ and M ² are the same or different; , Na, Li, K, 1 / 2Mg, 1 / 2Ba, 1 / 2Ca, aliphatic primary, secondary or tertiary amine, quaternary ammonium salt, or phosphonium salt. It is done.

  As the triazine derivative, in the present invention, 2,4,6-trimercapto-s-triazine, 2-dibutylamino-4,6-dimercapto-s-triazine, 2-anilino-4,6-dimercapto-s-triazine Is used. One of these triazine derivatives may be used alone, or two or more thereof may be used in combination. In view of availability, 2-dibutylamino-4,6-dimercapto-s-triazine and 2-anilino-4,6-dimercapto-s-triazine are particularly preferable.

  The triazine derivative is preferably blended at a ratio of 0.1 to 10 parts by mass with respect to 100 parts by mass of the rubber component. This is because when the blending amount of the triazine derivative is less than 0.1 parts by mass, the rubber component is insufficiently cross-linked so that the tackiness is exhibited and the wear resistance is inferior, while the blending amount of the triazine derivative is 10 parts by mass. This is because the effect on the strength is not seen even if it is used beyond the range. The blending amount of the triazine derivative is more preferably 0.5 parts by mass or more and 3 parts by mass or less with respect to 100 parts by mass of the rubber component.

As described above, butyl rubber having excellent gas permeation resistance and water vapor permeation resistance is used as the rubber component to be dynamically cross-linked. Examples of the butyl rubber include isobutylene-isoprene copolymer rubber and halogenated isobutylene-isoprene copolymer rubber. Of these, halogenated isobutylene-isoprene copolymer rubber is preferable because it can be easily finely dispersed by dynamic crosslinking.
As the rubber component, the butyl rubber may be used alone or in combination with ethylene-propylene-diene rubber (EPDM rubber) having excellent processability. When the halogenated isobutylene-isoprene copolymer rubber and EPDM are combined, the gas permeability resistance, water vapor resistance resistance and processability are excellent.
Examples of other rubber components combined with butyl rubber include nitrile rubbers such as isoprene rubber, butadiene rubber, styrene butadiene rubber, natural rubber, chloroprene rubber, and acrylonitrile butadiene rubber, hydrogenated nitrile rubber, norbornene rubber, Ethylene propylene rubber, ethylene-propylene-diene rubber, acrylic rubber, ethylene acrylate rubber, fluoro rubber, chlorosulfonated polyethylene rubber, epichlorohydrin rubber, silicone rubber, urethane rubber, polysulfide rubber, phosphansen rubber or 1,2 -Polybutadiene etc. are mentioned.

Polypropylene is used as the olefinic thermoplastic resin as the matrix.
Polypropylene has good compatibility with the rubber component and is excellent in processability because it has better fluidity than polyethylene. In addition, the melting point is higher than that of polyethylene, and the thermoplastic elastomer composition of the present invention at high temperatures. Compression set is improved.
The blending amount of the polypropylene is preferably 10 parts by weight or more and 80 parts by weight or less per 100 parts by weight of the rubber component. This is because if the amount is less than 10 parts by mass, the fluidity of the composition is poor and dynamic crosslinking is difficult, while if it is more than 80 parts by mass, preferable rubber elasticity cannot be obtained. Preferably it is 15-50 mass parts.

Further, a styrene thermoplastic elastomer is used as a matrix together with the polypropylene.
Examples of the styrenic thermoplastic elastomer include a block copolymer of a polymer block (A) mainly composed of a styrene monomer and a block (B) mainly composed of a conjugated diene compound, and a conjugated diene polymer unit of the block copolymer. The hydrogenated product can be exemplified. Examples of the styrene monomer include styrene, α-methyl styrene, vinyl toluene, and t-butyl styrene. These monomers may be used alone or in combination of two or more. Of these, styrene is preferable as the styrene monomer. Examples of the conjugated diene compound include butadiene, isoprene, chloroprene, and 2,3-dimethylbutadiene. These may be used alone or in combination of two or more.

  Among the styrene thermoplastic elastomers, it is more preferable to use a hydrogenated styrene thermoplastic elastomer. This is because the hydrogenated styrene thermoplastic elastomer has saturated double bonds by hydrogenation, has low hardness, has a small compression set, and is excellent in weather resistance and durability. Moreover, it is more preferable to use a hydrogenated styrene-based thermoplastic elastomer from the viewpoint that the elastomer composition after dynamic crosslinking can exhibit desired plasticity without inhibiting dynamic crosslinking of the rubber component. Furthermore, by adding a thermoplastic elastomer with good fluidity, the blending amount of the thermoplastic resin can be reduced while maintaining the fluidity of the thermoplastic elastomer composition of the present invention.

  Specific examples of the styrenic thermoplastic elastomer include styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), and styrene-ethylene / butylene-styrene copolymer (SEBS). Styrene-ethylene / propylene-styrene copolymer (SEPS) or styrene-ethylene-ethylene / propylene-styrene copolymer (SEEPS). Among these, it is particularly preferable to use a styrene-ethylene-ethylene / propylene-styrene copolymer (SEEPS).

  The styrenic thermoplastic elastomer is preferably blended in an amount of 20 to 50 parts by mass with respect to 100 parts by mass of the rubber component. This is because if the amount is more than 50 parts by mass, the small compression set at a high temperature of the thermoplastic elastomer (TPV) that performs dynamic crosslinking cannot be exhibited.

The thermoplastic elastomer composition may contain other components as long as the object of the present invention is not violated.
In the thermoplastic elastomer composition of the present invention, a known crosslinking aid may be used in order to appropriately perform the crosslinking reaction. Although a metal oxide is mentioned as a crosslinking adjuvant, The oxide of magnesium or calcium is preferable from a viewpoint which avoids use of a heavy metal. The blending amount of the crosslinking aid may be an amount that sufficiently exhibits the physical properties of the rubber component, and in the present invention, it is selected from the range of 0 to 5 parts by mass with respect to 100 parts by mass of the rubber component as necessary. Can do.

A softener may be blended in order to give appropriate flexibility and elasticity.
Examples of softeners include oils and plasticizers. As the oil, for example, a paraffinic, naphthenic or aromatic mineral oil or a synthetic oil known per se made of a hydrocarbon oligomer or a process oil can be used. As the synthetic oil, for example, an oligomer with α-olefin, an oligomer of butene, and an amorphous oligomer of ethylene and α-olefin are preferable. Examples of the plasticizer include dioctyl phthalate (DOP), dibutyl phthalate (DBP), dioctyl separate (DOS), dioctyl adipate (DOA), and the like.

The amount of the plasticizer is preferably 100 to 15 parts by mass with respect to 100 parts by mass of the rubber component. If the softening agent is blended more than the above range, the softening agent may bleed from the surface of the composition, or the softening agent may cause cross-linking inhibition and the rubber component may not be sufficiently cross-linked, resulting in a decrease in physical properties. is there. The lower limit of the blending amount of the softening agent is not particularly limited, as long as the effect of adding the softening agent, that is, the effect of improving the dispersibility of the rubber component at the time of dynamic crosslinking may be obtained, but usually 15 parts by mass or more It is.
In addition, as a method of mix | blending a softening agent, the method of kneading in addition to the composition before dynamic crosslinking, and the method of kneading to the whole after adding to a part in a composition previously are mentioned. In the latter case, for example, a method of adding an oil-extended ethylene propylene rubber to the composition or a method of adding an oil-extended hydrogenated styrene-based thermoplastic elastomer to the composition can be mentioned.

In order to improve the mechanical strength, a filler or the like can be blended as necessary.
Examples of the filler include silica, carbon black, clay, talc, calcium carbonate, and titanium oxide powder.
The filler is preferably blended at 30 parts by mass or less with respect to 100 parts by mass of the rubber component. It is because a softness | flexibility may fall when the ratio of a filler exceeds the said range. Moreover, it is not preferable also from a viewpoint of cleanliness.

In addition, in the thermoplastic elastomer composition of the present invention, addition of a lubricant, an anti-aging agent, an antioxidant, an ultraviolet absorber, a pigment, an antistatic agent, a flame retardant, a neutralizing agent, a nucleating agent, or an anti-bubble agent, etc. You may mix | blend an agent suitably.
Examples of the lubricant include higher fatty acid amides and unsaturated fatty acid amides.
Examples of the antiaging agent include imidazoles, amines, phenols and the like.

  In the thermoplastic elastomer composition used in the present invention, the triazine derivative is preferably 0.5 parts by mass or more and 3 parts by mass or less with respect to the rubber component, and the rubber component is a halogenated isobutylene-isoprene copolymer rubber, the olefin. Polypropylene resin, the styrene thermoplastic elastomer is a hydrogenated styrene thermoplastic elastomer, the polypropylene is 50 to 15 parts by mass with respect to 100 parts by mass of the rubber component, and the hydrogenated styrene thermoplastic elastomer is the rubber component. It is 50-20 mass parts with respect to 100 mass parts, Furthermore, 100-30 mass parts is mix | blended with the plasticizer with respect to 100 mass parts of said rubber components.

  The ink tube molded with the thermoplastic elastomer composition comprising the above components has flexibility and can reduce surface tackiness. In addition, since the compression set is small under high temperature use conditions, and further excellent in gas permeation resistance and water vapor permeation resistance, the ink is difficult to dry, and the ink can be kept in good fluidity. Further, the processability is good and the cost can be reduced. In particular, there is an advantage that elution of the zinc compound into the ink can be eliminated.

This invention provides the manufacturing method of the ink tube for the said inkjet printer as 2nd invention. The manufacturing method is as follows:
The components constituting the thermoplastic elastomer composition described above are kneaded, a shearing force is applied during the kneading to disperse the rubber component and dynamically cross-linked by the triazine derivative, and the rubber component is converted into the polypropylene and styrene-based heat. Obtaining a thermoplastic elastomer composition dispersed in a matrix made of a plastic elastomer,
The thermoplastic elastomer composition is put into an extruder and extruded into a tube shape to be molded.

  Specifically, a halogenated butyl rubber, a triazine derivative, polypropylene, and a hydrogenated styrene thermoplastic elastomer are put into a tumbler mixer or the like and mixed for about 15 minutes. The obtained mixture is put into a twin-screw extruder, and is heated to 150 to 250 ° C., preferably 180 to 220 ° C., and is kneaded while rotating and stirring at 200 rpm. Get the pellets. At that time, no zinc compound is blended.

  As described above, when crosslinking is performed while applying a shearing force, the rubber particle diameter in the composition can be set to several μm to several tens of μm and can be finely dispersed. By finely dispersing the rubber component, the adhesiveness of the surface of the molded product is improved. This effect is remarkable because butyl rubber having strong adhesiveness is used as the rubber component. In addition, since this effect is not affected by the thermoplastic resin and the thermoplastic elastomer, the relatively inexpensive polypropylene and the hydrogenated styrene thermoplastic elastomer described above can be used.

  The pellets of the thermoplastic elastomer composition obtained as described above were put into a single screw extruder used in the resin extrusion method, extruded at 20 rpm while heating at 190 to 220 ° C., and extruded into a tube shape. Get an ink tube.

  Although the shape of the ink tube formed by extrusion molding is not specified as described above, an outer diameter of 2 mm to 10 mm and a wall thickness of 0.5 mm to 3 mm are preferable. This is too thin at 0.5 mm, and it may not be possible to maintain low water vapor permeability and air permeability. If it exceeds 3 mm, the flexibility and flexibility of the ink tube will be insufficient, making it difficult to bend in the printer. Because.

As described above, the ink tube for an ink jet printer of the present invention is a thermoplastic elastomer composition used as a molding material thereof, since the rubber component is dynamically crosslinked with a triazine derivative and has a chemical crosslinking point. Low compression set and excellent heat resistance. In addition, since the rubber component is finely dispersed in the composition, the adhesiveness of the surface of the molded product can be improved. Furthermore, by using a triazine derivative, since a zinc compound as a crosslinking aid is not blended, elution of zinc can be prevented, and therefore, a contact substance is not contaminated.
And the thermoplastic elastomer composition used by this invention is excellent in a moldability, since a tube can be shape | molded by the extrusion molding similar to a thermoplastic resin. Furthermore, since the finishing process (for example, deburring, punching, etc.) of the molded product after crosslinking is not necessarily required, the cost can be reduced.
Thus, the ink tube of the present invention has flexibility, can reduce surface tackiness, has low compression set under high temperature use conditions, and is excellent in gas permeability resistance and water vapor permeability resistance. Therefore, the ink is difficult to dry, and the ink can be kept in good fluidity.

Hereinafter, an embodiment of an ink tube for an ink jet printer of the present invention will be described.
The ink tube is formed by extrusion using a thermoplastic elastomer composition.
In the thermoplastic elastomer composition, a rubber component is finely dispersed by dynamically cross-linking a rubber component in a matrix made of a thermoplastic resin and a thermoplastic elastomer using a cross-linking agent made of a triazine derivative.

  As the rubber component, a halogenated butyl rubber, preferably an isobutylene-isoprene copolymer rubber is used. Polypropylene is used as the thermoplastic resin, and a hydrogenated styrene thermoplastic elastomer is used as the thermoplastic elastomer. It is preferable to use a styrene-ethylene-ethylene / propylene-styrene copolymer (SEEPS) as the hydrogenated styrene-based thermoplastic elastomer.

  The polypropylene is 50 to 15 parts by mass with respect to 100 parts by mass of the rubber component, and the hydrogenated styrene-based thermoplastic elastomer is 50 to 20 parts by mass with respect to 100 parts by mass of the rubber component. And the plasticizer is mix | blended by 100-15 mass parts with respect to 100 mass parts of said rubber components, Preferably it is 30 mass parts or more. No zinc compound is blended.

  As the triazine derivative, 2-dibutylamino-4,6-dimercapto-s-triazine or 2-anilino-4,6-dimercapto-s-triazine is used. The triazine derivative is blended in an amount of 0.1 to 10 parts by weight, preferably 0.5 parts by weight or more and 3 parts by weight or less, based on 100 parts by weight of the rubber component.

The thermoplastic elastomer composition is produced by the following method.
A triazine derivative, a halogenated butyl rubber, polypropylene, a hydrogenated styrene thermoplastic elastomer, and a plasticizer are charged into a tumbler mixer and mixed.
This mixture is put into a twin-screw extruder, and is rotated and stirred at 200 rpm while being heated to 180 to 200 ° C., and a halogenated butyl rubber is dynamically crosslinked with a triazine derivative, and a matrix comprising a mixture of a hydrogenated styrene thermoplastic elastomer and polypropylene. Obtain pellets in which halogenated butyl rubber is dispersed.

  The obtained pellets of the thermoplastic elastomer composition are put into a single-screw extruder, extruded to a tube shape while being heated to 190 to 220 ° C. and rotated at 20 rpm, and an ink tube is obtained.

  The ink tube formed by extrusion as described above has an outer diameter of 2 mm to 10 mm and a wall thickness of 0.5 mm to 3 mm.

The acquired ink tube has a Shore A hardness of 40 to 60 according to JIS K6262.
The compression set is 40% or less, preferably 35% or less.
The tensile strength is 3.5 to 6.0 MPa, the water vapor permeation resistance is 0.3 or less, and, as a matter of course, there is no elution amount of the zinc compound.

Hereinafter, Examples 1-4 of the present invention and Comparative Examples 1 and 2 will be described in detail.
A dynamically crosslinked thermoplastic elastomer composition was produced using the components shown in Table 1, and an ink tube was produced using the obtained thermoplastic elastomer composition.

In Examples 1 and 2, 2-dibutylamino-4,6-dimercapto-s-triazine was blended as a crosslinking agent, and a resin crosslinking agent and zinc oxide were not blended. Example 1 blended more polypropylene than hydrogenated styrene thermoplastic elastomer, and Example 2 blended more hydrogenated styrene thermoplastic elastomer than polypropylene.
In Examples 3 and 4, 2-anilino-4,6-dimercapto-s-triazine was blended as a crosslinking agent, and a resin crosslinking agent and zinc oxide were not blended. Example 3 compounded more polypropylene than hydrogenated styrene thermoplastic elastomer, and Example 4 compounded more hydrogenated styrene thermoplastic elastomer than polypropylene.
In Comparative Examples 1 and 2, a triazine derivative was not blended and a resin crosslinking agent was blended. Moreover, Comparative Example 1 blended zinc oxide, while Comparative Example 2 did not blend zinc oxide.

The materials used are as follows.
Rubber component: Halogenated butyl rubber ("Butyl 1066" manufactured by ExxonMobil)
・ Thermoplastic resin: Polypropylene resin ("BC6" manufactured by Nippon Polychemical Co., Ltd.)
・ Thermoplastic elastomers: Hydrogenated styrene-based thermoplastic elastomers ("Septon 4077" manufactured by Kuraray Co., Ltd.)
Triazine derivative A; 2-di-n-butylamino-4,6-dimercapto-s-triazine (“DISNET DB” manufactured by Sankyo Kasei Co., Ltd.)
Triazine derivative B; 2-anilino-4,6-dimercapto-s-triazine (“DISNET AF” manufactured by Sankyo Kasei Co., Ltd.)
・ Softener: Paraffinic process oil (“Diana Process Oil PW-380” manufactured by Idemitsu Kosan Co., Ltd.)
Acid acceptor: Magnesium oxide (“Kyowa Mug 150” manufactured by Kyowa Chemical Industry Co., Ltd.)
・ Resin cross-linking agent; Halogenated alkylphenol resin cross-linking agent (“Tactrol 250-III” manufactured by Taoka Chemical Industries, Ltd.)
・ Zinc oxide; 2 types of zinc oxide (Mitsui Mine Co., Ltd.)

The manufacturing method was as follows.
The components listed in Table 1 were blended in the proportions shown in Table 1, mixed for 15 minutes with a tumbler, and then rotated at 180 to 200 ° C. with a twin screw extruder (“HTM38” manufactured by Ipec). Dynamic crosslinking was carried out by kneading at 200 rpm to produce a thermoplastic elastomer composition and pelletized.
The obtained pellets were put into a φ50 single screw extruder (manufactured by Kasamatsu Processing Laboratory Co., Ltd.), heated to 190 to 220 ° C., and extruded into a tube shape at 20 rpm.

Various evaluations were performed on the ink tubes of Examples and Comparative Examples by the methods described later. The evaluation results are shown in Table 1.
(Hardness)
In accordance with JIS K 6253, a type A durometer hardness test was performed under constant temperature and humidity conditions of an ambient temperature of 23 ° C. and a relative humidity of 55%.
(Compression set)
A compression set test was performed in accordance with JIS K 6262. The measurement was performed at a measurement temperature of 70 ° C., a measurement time of 24 hours, and a compression rate of 25%.
(Water vapor permeation resistance)
The formed ink tube was cut to a length of 100 mm, a fixed mass of pure water was injected into the tube, and both ends were sealed with clips. After measuring the mass (initial mass) of the ink tube sealed with pure water, the ink tube was left in an oven at a temperature of 50 ° C. and a humidity of 55% for 7 days. Thereafter, the mass of the ink tube was measured, and the difference from the initial mass was taken as the mass of the reduced water. The water vapor permeability was calculated from (reduced water mass / injected water mass).
(Elution amount of zinc compound into ink for inkjet printer)
1 g of the molded ink tube was immersed in 2 ml of a commercially available ink for inkjet printers (Canon FINE Cartridge BC70) and left in an oven at a temperature of 50 ° C. and a humidity of 55% for 7 days. Thereafter, the ink was acid-decomposed and zinc was quantified by ICP-MS (inductively coupled plasma mass spectrometer). Results are shown in ppm.

The water vapor permeation resistance was 0.26 in Example 1 and 0.25 in Examples 2 to 4. The water vapor permeation resistance was good, and the zinc compound did not elute into the ink.
The compression set ratios of Examples 1 to 4 are lower than those of Comparative Example 2 in which zinc oxide was not blended, and are substantially the same as Comparative Example 1 in which zinc oxide was blended. did it.
Comparative Example 1 is an ink tube made of a thermoplastic elastomer composition in which zinc oxide is blended and a rubber component is dynamically crosslinked using a resin crosslinked product and dispersed in a matrix. Although good physical properties were obtained as a whole, the zinc compound was eluted into the ink because zinc oxide was blended.
In Comparative Example 2, dynamic crosslinking was performed using a resin crosslinking agent in the same manner as in Comparative Example 1, but since zinc oxide was not blended, crosslinking was not sufficient. Therefore, the tensile strength was low, the compression set was large, the water vapor permeability was low, and the physical properties did not meet the standards for practical use.

Claims (5)

A rubber component containing butyl rubber, an olefin resin containing polypropylene, a thermoplastic elastomer containing a styrene thermoplastic elastomer, and a crosslinking agent composed of a triazine derivative are blended, while a zinc compound is not blended,
An ink tube for an ink jet printer, which is formed from a thermoplastic elastomer composition in which the rubber component is dynamically cross-linked and dispersed by the cross-linking agent in a matrix composed of the olefin resin and the thermoplastic elastomer.   In the said thermoplastic elastomer composition, the crosslinking agent which consists of a triazine derivative is mix | blended in 0.1 mass part or more and 10 mass parts or less with respect to 100 mass parts of said rubber components. Ink tube. In the thermoplastic elastomer composition, the rubber component is a halogenated isobutylene-isoprene copolymer rubber, the olefin resin is polypropylene, the styrene thermoplastic elastomer is a hydrogenated styrene thermoplastic elastomer,
The polypropylene is 50 to 15 parts by mass with respect to 100 parts by mass of the rubber component, the hydrogenated styrene-based thermoplastic elastomer is 50 to 20 parts by mass with respect to 100 parts by mass of the rubber component,
The ink tube for an inkjet printer according to claim 1 or 2, wherein a plasticizer is blended in an amount of 100 to 30 parts by mass with respect to 100 parts by mass of the rubber component.   The ink tube for an ink jet printer according to any one of claims 1 to 3, which has an outer diameter of 2 mm to 10 mm and a thickness of 0.5 mm to 3 mm. A method for producing an ink tube for an ink jet printer according to any one of claims 1 to 4,
The components constituting the thermoplastic elastomer composition are kneaded, a shearing force is applied during the kneading to disperse the rubber component and dynamically cross-linked by the triazine derivative, and the rubber component is converted to the polypropylene and styrene thermoplastics. Obtain a thermoplastic elastomer composition dispersed in a matrix made of elastomer,
A method for producing an ink tube for an ink jet printer, wherein the thermoplastic elastomer composition is put into an extruder and extruded into a tube shape.