JP2000096407A - Waste fluid absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce waste fluid absorber comprising a matrix fiber and a thermally meltable and adhesive fiber, and useful for absorbing waste fluid arising from a print head of a press (e.g. an ink-jet printer, a plotter, a facsimile machine). SOLUTION: This waste fluid absorber is produced by making nonwoven fabric of matrix fibers and thermally meltable and adhesive fibers (pref. through opening, carding and cross-laying processes), by heat-treating the non-woven fabric to partially melt and adhere and by interlacing the fibers three- dimensionally. Spunbonded fabric is pref. laminated on the one surface of the above absorber. When extruding once absorbed and held ink from the absorber with an air pump, bubbles don't arise on the surface of the absorber, and the absorber retains rigidity and excellent dimensional stability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer, a plotter, a facsimile, etc., which are suitably used for a waste liquid absorber for absorbing waste liquid generated in a print head of a printing machine.

[0002]

2. Description of the Related Art An ink jet printer that performs printing by ejecting ink from a nozzle of a print head onto recording paper is known.
In order to maintain a certain printing function, it is necessary to clean nozzles before printing. For this cleaning, a very small amount of ink is ejected from the nozzle. As a result, the solid content, impurities, and the like of the ink remaining in the nozzles are extruded, and it is possible to suppress generation of bubbles and defective ejection.

In order to temporarily absorb and hold the ink ejected at this time, a continuous foam made mainly of polyurethane or polyvinyl alcohol is used as a waste liquid absorber near the nozzle. For example, in Japanese Patent Application Laid-Open No. 9-220812, water-soluble polyvinyl alcohol is used as a catalyst with an acid,
It is described that a continuous foam obtained by binding formaldehyde is used as a waste liquid absorber.

[0004] Further, the ink once absorbed and held by the waste liquid absorber is pushed out by an air pump and finally sent to a waste liquid tank to be stored.

However, since these waste liquid absorbers are continuous foams, pores are scattered on the surface for directly receiving ink. For this reason, when the ink once held in the waste liquid absorber is pushed out to the waste liquid tank by an air pump, bubbles are generated on the surface of the absorber if the ink adheres to the pores. When this bubble bursts, the ink scatters and solidifies in the print head, causing a problem that the nozzle becomes defective in ejection.

In particular, a large amount of a surfactant is used in ink to disperse the pigment in a solvent, and bubbles are easily generated.

Further, such a continuous foam has a low strength as an absorber, and therefore swells when absorbing ink.
For this reason, this may cause cracks and the like in the case holding the waste liquid absorber, and improvement in dimensional stability has been desired.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent ink from being absorbed and held by an air pump to a waste liquid tank without bubbles on the surface, maintain appropriate air permeability and rigidity, and maintain dimensional stability. To provide an excellent waste liquid absorber.

[0009]

Means for Solving the Problems The present inventors have studied the selection, blending, and manufacturing method of the materials constituting the absorber, and have completed the present invention. That is, the waste liquid absorber is composed of a matrix fiber and a heat fusion fiber.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The polymer of the matrix fiber and the heat fusible fiber used in the present invention is not particularly limited. For example, in the case of synthetic fibers, aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate; aliphatic polyesters such as polylactic acid and polycaprolactone; polyolefins such as polypropylene and polyethylene; polyamides such as nylon 6 and nylon 66; And the like can be used. Further, a mixture of two or more of these fibers may be used.

[0011] Natural fibers can also be used as the matrix fibers. In this case, cellulose, wool, cotton,
Silk or the like can be used. Further, a mixture of two or more of these fibers may be used.

The heat-fusible fiber may be a single-component fiber made of the above-mentioned polymer, but if a sheath-core conjugate fiber having a low-melting polymer for the sheath component and a higher-melting polymer for the core component is used. This is more preferable because the heat-sealing function can be achieved while maintaining the function of supporting the core component. As such heat-fused fibers, Bellcombi of Kanebo Synthetic Co., Ltd., which has ordinary polyethylene terephthalate polymer as a core component and low melting point copolymerized polyethylene terephthalate polymer as a sheath component, is already commercially available, but is not limited thereto. Do not.

The waste liquid absorber of the present invention needs to be composed of these matrix fibers and heat-fused fibers. When matrix fibers and heat-fusible fibers are used, pores are not formed on the surface of the non-woven fabric as in a continuous foam made mainly of polyurethane or polyvinyl alcohol. For this reason, when pushing out the retained ink to the waste liquid tank with an air pump,
The generation of bubbles can be suppressed. Further, since the bonding is performed by the heat-fusible fibers, the matrix fibers in the nonwoven fabric are heat-bonded at the heat-fused fibers or at the entangled portions of the heat-fusible fibers. Therefore, swelling is suppressed during ink absorption, and excellent dimensional stability can be maintained.

The ratio between the matrix fibers and the heat-fusible fibers is 9
The ratio is preferably 0:10 to 20:80. Within this range, the adhesion at the intersection of the matrix fibers and the heat-fused fibers, or between the heat-fused fibers, is sufficient. In addition to imparting morphological stability to the nonwoven fabric substrate, it is possible to maintain appropriate rigidity. Becomes For this reason, it is preferable because the punching process at the time of producing a product becomes easy.

The matrix fibers and the heat-fusible fibers can be subjected to a heat treatment after being formed into a nonwoven fabric by opening, carding, or cross-laying, and then heat-sealed to be three-dimensionally entangled. By such a heat treatment, the matrix fiber and the heat-fused fiber, or at the intersection of the heat-fused fibers, are bonded to each other to impart morphological stability to the nonwoven fabric substrate, and it is also possible to intentionally impart irregularities to the nonwoven fabric substrate. Becomes

The heat treatment is carried out at a temperature higher than the temperature at which the heat-fusible fiber exhibits the fusibility, but it may be carried out as a single step or in conjunction with the heat molding step.

The fineness of the matrix fiber and the heat fusible fiber is 2
Preferably it is ~ 15 denier. When it is within this range, appropriate air permeability can be obtained, so that the ink once absorbed and held can be smoothly pushed out to the waste liquid tank. Therefore, clogging due to the solid content of the ink is suppressed, which is preferable. Further, when it is within this range, it is possible to maintain appropriate rigidity. For this reason, it is preferable because the punching process at the time of producing a product becomes easy.

In order to control the air permeability and rigidity of the waste liquid absorber, it is possible to mix two or more types of fine fibers. Normally, the air permeability and the rigidity increase as the mixing ratio of the fibers having a large fineness increases. These mixing ratios can be appropriately changed depending on the site where the waste liquid absorber is actually used.

The waste liquid absorber of the present invention has a thickness of 0.5 mm.
It is preferable that it is above. When it is 0.5 mm or more, it is possible to maintain appropriate rigidity. For this reason, it is preferable because the punching process at the time of producing a product becomes easy.

The waste liquid absorber of the present invention has a density of 0.0
It is preferably from 0.5 to 0.3 g / cm ³ . Within this range, moderate rigidity can be maintained, and
This is preferable because unevenness in the basis weight does not occur.

Further, it is preferable that a spun bond is laminated on one side of the waste liquid absorber. If there is a part of the waste liquid absorber where the adhesion between the matrix fiber and the heat fusion fiber is insufficient, fluff will be generated on the surface and it will be in contact with the nozzle, which will cause discharge failure. This is preferable because the generation of fluff is suppressed.

The spunbond polymer is not particularly limited. In the case of synthetic fibers, aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate; aliphatic polyesters such as polylactic acid and polycaprolactone; polyolefins such as polypropylene and polyethylene; polyamides such as nylon 6 and nylon 66; Copolymers and the like can be used.

The lamination of the waste liquid absorber and the spun bond is performed by superposing the spun bond on one surface of the waste liquid absorber and then performing a heat treatment. The heat treatment is performed at a temperature equal to or higher than the temperature at which the heat-fusible fibers exhibit the fusibility, whereby the heat-fusible fibers present on the surface of the waste liquid absorber can adhere to the spun bond.

[0024]

According to the present invention, when the ink once absorbed and retained is pushed out to the waste liquid tank by an air pump, bubbles are not generated on the surface, and the waste liquid absorbent body which has appropriate permeable property and rigidity and has excellent dimensional stability. It is.

[0025]

EXAMPLES (Method of Measuring and Evaluating Generation of Bubbles) A sample is cut into 1 cm × 2 cm. At the same time as ink is dropped from the surface of the sample, air is blown from the side by an air pump to push out the ink. At this time, whether or not bubbles are generated on the sample surface is visually observed. The evaluation was ◎ if no bubbles were generated, ○ if it was generated occasionally, and Δ if it was constantly generated.

(Method of Measuring and Evaluating Air Permeability of Waste Liquid Absorber) The Frazier-type air permeability was measured by KES-F8AP1 manufactured by Kato Tech Co., Ltd., and the amount of air passing through a unit area within a unit time was measured. . The evaluation was performed when the ventilation rate was 400 cc / cm ² / s or more, and 200 cc / cm ² /
s and less than 400 cc / cm ² / s, 200 cc / cm
Less than cm ² / s was defined as Δ.

(Method of Measuring and Evaluating Stiffness of Waste Liquid Absorber) The bending resilience was measured by the Gurley method based on JIS L 1018. A sample is cut into a size of 3 cm × 5 cm, and one end is fixed to a movable arm of a testing machine and rotated at a constant speed. At this time, the scale at which the sample separates from the pendulum is measured, and the rigidity is calculated. Evaluation is 500mgf rigidity
If it was more than ◎, it was ◎ if it was 300 mgf or more and less than 500 mgf;

(Method of Measuring and Evaluating Fluff Generation)
It is visually observed whether fluff is generated on the sample surface. The evaluation was ◎ if no fluff was generated at all, て い if it was generated in some places, and △ if it was generated all over.

Example 1 A waste liquid absorber having the composition shown in Table 1 was produced by performing carding and cross-laying and then performing a heat treatment at 150 ° C. for 90 seconds. Even when the ink was dropped on the surface of the manufactured waste liquid absorber and the ink was pushed out from the side by an air pump, no bubbles were generated on the surface. The ventilation rate was 560 cc / cm ² / s, the rigidity was 365 mgf, and fluff was generated in some places. Table 2 shows the evaluation results.

Example 2 A waste liquid absorber having the composition shown in Table 1 was produced by performing carding and cross-laying and then performing a heat treatment at 150 ° C. for 90 seconds. Even when the ink was dropped on the surface of the manufactured waste liquid absorber and the ink was pushed out from the side by an air pump, no bubbles were generated on the surface. The air permeability was 420 cc / cm ² / s, the rigidity was 418 mgf, and no fluff was generated. Table 2 shows the evaluation results.

Comparative Example 1 A continuous foam obtained by binding formaldehyde to water-soluble polyvinyl alcohol using an acid as a catalyst was used. 0.8mm thick, 0.125g / c density
It was m ^3. Drop ink on the surface of this continuous foam,
When the ink was pushed out from the side by an air pump, bubbles were constantly generated on the surface. The ventilation rate is 681 cc / cm ²
/ S, the rigidity was 292 mgf, and no fluff was generated. Table 2 shows the evaluation results.

[0032]

[Table 1]

[0033]

[Table 2]

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4L047 AA12 AA21 AA27 AA28 AB02 BA09 BB06 BB09 BD01 CA05 CB01 CB07 CB08 CC14

Claims (3)

[Claims] 1. A waste liquid absorber comprising a matrix fiber and a heat fusible fiber. 2. A structure in which the matrix fiber and the heat-fused fiber are formed into a non-woven fabric by opening, carding, and cross-laying, and then subjected to a heat treatment, heat-fused, and three-dimensionally entangled. The waste liquid absorber according to claim 1. 3. The waste liquid absorber according to claim 1, wherein a spun bond is laminated on one surface of the waste liquid absorber.