JP2005336501A - Ink waste liquid absorbent and its production - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an (printer) ink waste liquid absorbent which is homogeneous, accurate, and inexpensive, has high ink absorbency, can be cut in the shape of a set site in a printer and then used, does not cause such a fuzzing phenomenon as that of felt, does not fall fuzzes and the like, and does not affect the functions of a printer. <P>SOLUTION: This ink waste liquid absorbent is characterized by subjecting a flexible urethane foam produced from foaming raw materials comprising a polyol, an isocyanate, a catalyst and a foaming agent to a dipping treatment using a surfactant. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink waste liquid absorber with improved absorbability of pigment and dye inks and a method for producing the same.

  In recent years, with the spread of personal computers, many types of printers have been provided. In recent years, these printers have shifted from a wire dot method or an ink ribbon method to a laser method or an ink jet method. In particular, the ink jet method is less expensive than the laser method and is widely used. Conventionally, dye inks have been widely used in such ink jet printers, but pigment inks have come to be used with the recent development of color printers.

  In this case, in the ink jet printer, excess ink is accumulated in the printer due to cleaning of the printer head or the like, but this may flow out and stain the vicinity of the printer head. For this reason, an ink absorbing material that absorbs excess ink is spread over the printer head.

  The ink absorbing material was initially a pulp or a fibrous nonwoven fabric, but since the fibers are scattered in the printer due to feathering, a flexible polyurethane foam sheet has been widely used in recent years. Further, since the ink is changing from dye ink to pigment ink, this soft polyurethane foam sheet is also improved in ink absorbability. In particular, since pigment ink is used in a dispersed state with fine particles of carbon or the like, it cannot be denied that the absorptivity differs from dye ink. In particular, for ink absorbing materials, the particles such as carbon are clogged, and conventional ink absorbing materials often do not exhibit sufficient absorbing performance.

  Due to the downsizing and weight reduction of printers, it is often difficult to spread this ink absorbent at a position that directly corresponds to the printer head. For this reason, the original ink is located at a position slightly different from the printer head. There is a case in which an absorbent material is spread and an absorbent material (conducting material) that serves as a path for ink between the printer head and a bridge is bridged. However, an ink waste liquid absorber (conducting material, absorbing material) with further improved performance is desired.

Japanese Patent Laid-Open No. 10-110053

  This invention improves the said situation, and it aims at providing the ink waste-liquid absorber with sufficient absorbency with respect to dye ink and pigment ink, and its manufacturing method.

  The first gist of the present invention is excellent in ink absorbency characterized by impregnating a surfactant into a flexible polyurethane foam produced using a foaming raw material containing a polyol, an isocyanate, a catalyst, and a foaming agent. Ink waste liquid absorber, preferably the surfactant is a sodium succinate modified product.

  The second gist of the present invention is to obtain a flexible polyurethane foam using a foaming raw material containing a polyol, an isocyanate, a catalyst and a foaming agent, and after compression molding as necessary, the above-mentioned flexible polyurethane foam or water in a surfactant-dispersed water. A method for producing an ink waste liquid absorber excellent in ink absorption, characterized in that the compressed body is immersed, water is squeezed and then dried to attach a surfactant to the surface of the flexible polyurethane foam or the compressed body It depends on.

  Here, the ink waste liquid absorber is applied to any form of the ink conducting material or the ink absorbing material corresponding to the printer head, and the ink absorber brought into contact with the ink conducting material.

  The ink waste liquid absorber of the present invention is excellent in absorbability of ink, particularly pigment ink, is equal to or better than that of current pulp and felt, and provides performance higher than that of a highly water absorbent foam. That is, there is an absorbent material in which a flexible polyurethane foam is hot pressed as a highly water-absorbing foam to improve the absorbability due to capillary action, but when this is used as it is for the absorption of pigment ink, carbon such as carbon in the pigment component Clogging due to the particles occurs, and the absorption performance is extremely inferior.

  For this reason, the ability to quickly absorb and retain the pigment ink is required, and the conductive material used as a bridging material with the absorbing material as described above has a smaller capillary effect than the absorbing material, and when dried ( It must have the ability to prevent ink clogging and poor absorption when not in use), but the present invention impregnates the pigment ink by impregnating with a surfactant to improve the absorption of the pigment ink. Is improved.

  According to the present invention, it is possible to obtain a uniform and precise ink waste liquid absorber with high ink absorbability, and even if the shape of the set part in the printer is complicated, it should be cut according to the shape and used. Thus, an inexpensive printer ink waste liquid absorber can be provided. Since the ink waste liquid absorber is a polyurethane foam, there is no fuzzing phenomenon unlike felt, and there is a feature that the function of the printer is not adversely affected without the fluff falling off.

Hereinafter, the present invention will be described in more detail.
In the present invention, the flexible polyurethane foam used for forming the ink waste liquid absorber is produced using a foaming raw material containing a polyol, an isocyanate, a catalyst, and a foaming agent.

  In this case, a preferred polyol is a poly (oxyethylene-oxyalkylene) polyether polyol obtained by adding an alkylene oxide other than ethylene oxide and ethylene oxide to an active hydrogen-containing compound having 2 or more functional groups. Here, examples of the alkylene oxide component include propylene oxide, butylene oxide, styrene oxide and the like. Examples of the active hydrogen-containing compound used for producing the polyol include polyalcohols and polyamines. Examples of polyalcohols include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, 1, 2, and the like. 6-hexanetriol, pentaerythritol, sorbitol, sucrose, etc.

  In addition, as the polyol used in the present invention, a hydrophilic organic acid metal salt and / or its polymer-containing polyol can also be used as part of the polyol, and organic acids such as potassium, magnesium, tin, copper, lithium, Silver or the like is effective, and potassium and sodium are preferable. Such a polyol is used by blending with a polyol used for production of a normal flexible polyurethane foam.

  The organic isocyanate used for reacting with the polyol is not particularly limited, and examples thereof include toluene diisocyanate, phenylene diisocyanate, diphenylmethane diisocyanate, and 4,4'-diphenyl diisocyanate. Among these, toluene diisocyanate having a 2,4- / 2,6-isomer ratio of 80/20 or 65/35 is preferable from the viewpoint of economy, and is based on the total amount of polyol and other compounds having active hydrogen. The amount of the organic isocyanate used, that is, the isocyanate index is in the range of 80 to 130, but is preferably in the range of 100 to 110.

  Examples of the catalyst include an organic tin compound catalyst and an amine catalyst. Examples of organotin compound catalysts include stannous octoate, stannous oleate, dibutylditin laurate, dibutyltin di-2-ethylhexoate, and dibutyltin diacetate. On the other hand, as the amine catalyst, amine catalysts generally used, for example, triethylamine, triethylenediamine, N-ethylmorpholine, dimethylethanolamine, dimethylbenzylamine, 1,8-diazabicyclo (5.4.0) undecene- 7 and phenol salts thereof, triethylenediamine formate, and the like can be used as they are. These catalysts are used alone or in admixture of two or more. As the amine-based catalyst, an amine-based catalyst usually used for foaming flexible polyurethane foam is used, but a reactive amine-based catalyst is preferably used for applications where elution is a problem. Although the usage-amount of a catalyst is not specifically limited and can be changed in a wide range, Usually, it is the range of 0.005-2 weight part with respect to 100 weight part of polyols.

  Furthermore, as for the foam stabilizer, silicone-based foam stabilizers usually used for foaming flexible polyurethane foams are used, but for applications where elution is a problem, reactive foam stabilizers are also used. Use is preferred. The amount used can be 0.1 to 3.0 parts by weight with respect to 100 parts by weight of polyol, and 0.5 to 2.0 parts by weight is particularly preferable.

  As the foaming agent, water, methylene chloride, or a volatile liquid having a low boiling point is used.

  In addition to the above-described blending components, a filler, an antistatic agent, a colorant, a flame retardant, and the like can be added according to the performance required for the foam without departing from the object of the present invention.

  Of course, when a material having a high hardness is desired, a crosslinking material or the like can be blended.

As a method for producing a flexible polyurethane foam using the above foaming raw material, a conventional method is adopted, but the obtained flexible polyurethane foam has a density of 0.005 to 0.150 g / cm ³ , particularly 0.01 to 0.05 g. / is preferably cm is ^3, also the number of cells is 40 to 150 pieces / 25 mm, it is preferable in particular 60 to 150 pieces / 25 mm. In this case, when the flexible polyurethane foam is compressed and used, the number of cells is preferably 20 to 150/25 mm, particularly 40 to 150/25 mm, and more preferably 40 to 100/25 mm.

  In the present invention, the flexible polyurethane foam is not compressed (as it is uncompressed foam) or is compressed (compressed foam), and the surfactant is attached.

  Here, as the surfactant, anionic surfactants such as ethylene oxide, higher fatty acid alkali salts and alkyl sulfonates, cationic surfactants such as higher amine halogenates and quaternary ammonium salts, polyethylene glycol alkyl ethers, sorbitans, etc. Any of nonionic surfactants such as fatty acid esters and amphoteric surfactants such as amino acids can be used. Among these, a sodium succinate modified product is particularly preferably used in terms of effects. In this case, as the modified sodium succinate, succinic acid dialkyl ester sulfonic acid soda represented by the following formula is preferably used.

（但し、Ｒはアルキル基又はアラルキル基であり、炭素数１〜１８のものが挙げられる。）

(However, R is an alkyl group or an aralkyl group, and a C1-C18 thing is mentioned.)

  Specific examples of the ester include di-n-amyl, di-n-hexyl, di-n-heptyl, di-n-octyl, di-n-nonyl, monoethyl monododecyl, monobutyl monododecyl, and mono-2. -Ethylhexyl-mono-1-methylbenzyl, mono-2-ethylhexyl-mono-1-methyl-4-ethylhexyl, di-1-methylbutyl, di-2-methylbutyl, di-isoamyl, di-1,3-dimethylbutyl , Di-1-methylamyl, di-dimethylamyl, di-1-isopropylisobutyl, di-1-propylbutyl, di-1-methylhexyl, di-2-ethylhexyl, di-1-methylheptyl, di-1- Butyl amyl, di-1-isobutyl-3-methylbutyl, di-1-methyl-4-ethylhexyl, di-1-methyl-4-ethyloctyl, etc. And the like.

Such surfactants are preferably water-soluble, since they only need to be dried after impregnating the foam. The amount of the surfactant impregnated varies depending on the required performance. For example, in the case of a modified sodium succinate, 1 to 500,000 g / m ³ , preferably 1 to 100,000 g / m. ³ and more preferably about 1,000 to 20,000 g / m ³ .

  As a method for attaching the surfactant, a method in which an uncompressed foam or a compressed foam is immersed in water in which the surfactant is dispersed or dissolved, taken out, squeezed out, and then dried is suitably employed.

  The flexible polyurethane foam may be non-compressed or compressed as described above, but the compression ratio can be 1 to 20 times. Here, the compression ratio of 1 is in an uncompressed state, and therefore the compressed foam may be a slightly compressed non-compressed foam, but usually 2 to 20 times, more preferably What was compressed 5-10 times, more preferably 8-10 times is used. In addition, although there is no limitation in the compression method, the hot press method is employ | adopted normally, The method of compressing to predetermined magnification using a hot plate of about 150-240 degreeC, and fixing to this compression magnification is employable. The hot press time is not particularly limited, but can be, for example, about 2 to 20 minutes.

  In addition, when the ink waste liquid absorber of the present invention is used as an ink absorbing material, for example, in contact with an ink conducting material, a plurality of layers having different air permeability are increased from the ink absorbing side, and the ink absorbing side is increased. It is preferable to use a laminate in which the ink holding capacity is increased as the distance from the head increases, that is, the ink absorption side has a high air permeability, and the air permeability is sequentially reduced. For example, the ink absorption side can be an uncompressed foam and the opposite side can be a compressed foam, or the ink absorption side can be laminated so that the compression ratio increases sequentially.

  As a means for forming a multi-layer structure in this way, a method of laminating two to six layers, particularly about 3 to 5 layers having different compression ratios and / or cell numbers is employed. Further, when the foam is thermally compressed, it may be compressed by applying a hot plate to only one side of the foam.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In addition, a part shows a mass part by the following example.

[Examples, Comparative Example I]
(Manufacture of foam)
The production blend of the flexible polyurethane foam used here and the blend blend of the absorbent polyurethane foam conventionally used as an absorbent material are polyol (V3030, manufactured by Dow Co., Ltd.), 100 parts, TDI80 (manufactured by Nippon Polyurethane Co., Ltd.), 50 parts, water, 4 parts, amine-based catalyst (DABCO-33LV, manufactured by Mitsui Air Products), 0.3 part, tin catalyst (stanas octoate, manufactured by Nitto Kasei), 0.3 part, silicone foam stabilizer (L-520, made by Nippon Unica Co., Ltd.) 1 part, and a flexible polyurethane foam was obtained by a one-shot method. The obtained foam had a density (JIS-K6400) of 0.020 g / cm ³ and a cell number of 55.

Next, the obtained foam (10 mm × 100 mm × 100 mm) was immersed in water in which sodium di- (normal octyl) sulfosuccinate was dissolved, taken out, squeezed out, and dried by heating (Example). The amount of sodium di- (normal octyl) sulfosuccinate was 3,000 g / m ³ .

(Absorption test)
An absorption test was performed on the foam of the example impregnated with sodium di- (normal octyl) sulfosuccinate and the untreated foam (comparative example).
(1) 0.1 cc of pigment ink was dropped on the test piece, and the suction speed (second) was measured. As a result of the measurement, the foam of the present invention absorbed within 1 second, but the comparative foam required more than 60 seconds.
(2) 0.1 cc of pigment ink was dropped on the test piece, and the suction speed (seconds) after repeating this 10 times was measured. The foam of the present invention absorbed within 1 second, but the foam of the comparative example required more than 60 seconds.

(Absorption state)
(3) When the absorption state was examined, in the foam of the present invention, absorption was performed vertically from the ink dropping position to the bottom of the test piece in a cylindrical shape, and no clogging of the pigment ink was observed.
On the other hand, in the foam of the comparative example, a clogging layer is seen on the surface, and the ink dropping point spreads and does not reach the bottom uniformly. This was inferior in the quick absorbability of the ink, and was unpreferable as a bridge material to other absorbent holding materials.

[Examples, Comparative Example II]
The foam (50 mm × 100 mm × 100 mm) obtained above was hot-pressed with a hot plate at 200 ° C. for 300 seconds to obtain a 5-fold press product (compression rate 5 times, 10 mm × 100 mm × 100 mm).
This compressed foam was impregnated with sodium di- (normal octyl) sulfosuccinate in the same manner as in Example I above, and 3,000 g / m ^{3 of} sodium di- (normal octyl) sulfosuccinate was deposited (Example).

The absorption test of the compression foam of the obtained Example and the untreated compression foam (comparative example) was conducted.
(1) 0.1 cc of pigment ink was dropped on the test piece, and the suction speed (second) was measured. As a result of the measurement, the foam of the present invention absorbed within 1 second, whereas the comparative foam required 20 seconds.
(2) 0.1 cc of pigment ink was dropped on the test piece, and the suction speed (seconds) after repeating this 10 times was measured. The foam of the present invention absorbed within 1 second, but the foam of the comparative example required 15 seconds.

Claims (12)

  An ink waste liquid absorber, wherein a flexible polyurethane foam produced using a foaming raw material containing a polyol, an isocyanate, a catalyst, and a foaming agent is impregnated with a surfactant.   The waste liquid absorber according to claim 1, wherein the flexible polyurethane foam is an uncompressed foam.   The waste liquid absorber according to claim 1, wherein the flexible polyurethane foam is a compression foam.   The waste liquid absorber according to any one of claims 1 to 3, wherein the surfactant is a modified sodium succinate. The waste liquid absorber according to claim 4, comprising 1 to 500,000 g / m ^{3 of a} modified sodium succinate. The waste liquid absorber according to claim 5, comprising 1,000 to 20,000 g / m ^{3 of a} modified sodium succinate.   The surface of the flexible polyurethane foam is obtained by using a foaming raw material containing a polyol, isocyanate, catalyst and foaming agent to obtain a flexible polyurethane foam, immersing the flexible polyurethane foam in water in which a surfactant is dispersed, squeezing the water and then drying. A method for producing an ink waste liquid absorber, characterized in that a surfactant is adhered to the ink.   The process according to claim 7, wherein the flexible polyurethane foam to which the surfactant is attached is further compression molded.   8. The process according to claim 7, wherein a compressed body of the flexible polyurethane foam obtained by compression molding the flexible polyurethane foam is immersed in water in which a surfactant is dispersed.   The method according to claim 7, 8 or 9, wherein the surfactant is a modified sodium succinate. The manufacturing method of Claim 10 which contained 1-500,000 g / m < ³ > of sodium succinate modified products. The manufacturing method of Claim 11 which contained 1,000-20,000g / m < ³ > modified sodium succinate.