JP3175238B2 - Inkjet recording material and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording material used for ink-jet recording by coating a substrate with an anionic coating composition mainly comprising a pigment and an aqueous binder, and a method for producing the same. . More specifically, the present invention relates to a recording material having excellent ink absorbability and capable of forming a high-resolution, water-resistant recording image and a method for producing the same.

[0002]

2. Description of the Related Art In an ink jet recording system, fine droplets of ink are generated and fly by various operating principles.
The recording is performed by adhering to a recording material such as paper.
This method has been rapidly spread as a recording method that generates little noise and can perform high-speed printing and multicolor printing.

As a recording material used in the ink jet recording method, ordinary paper has been generally used. However, with the improvement of device performance and the expansion of applications such as high-speed recording and multi-color recording, recording materials for inkjet have been required to have higher characteristics.

That is, in order to obtain a high-resolution and high-quality recorded image comparable to that of a color photograph, a recording material is required to satisfy the following various requirements. (1) Ink absorption is quick, (2) When ink dots overlap, ink that has adhered later does not flow to the previous dot, and (3) The shape of the ink dot is close to a perfect circle. (4) that the diameter of the ink dots does not become larger than necessary, (5) the density of the ink dots is high, and the periphery of the dots does not blur,
(6) The color development of the ink is excellent. Further, water resistance and light resistance have been required more than before.

However, a recording material that satisfies all of these requirements has not been found yet. For example, in order to enhance the ink absorption, a sheet containing a urea-formaldehyde resin powder is impregnated with a water-soluble polymer (Japanese Patent Application Laid-Open No. 53-49113), or an ink-absorbing coating layer is provided ( JP-A-55-5830) and non-colloidal silica powder used as a pigment in a coating layer (JP-A-55-51583) are known. Although the ink absorbency was improved by these methods, they were not always sufficient.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording material which gives an excellent recorded image when used in an ink jet recording system. In a recording material for ink jet recording in which a coating composition is applied on a substrate, an object is to provide a recording material having excellent ink absorbency, high resolution, and highly improved water resistance. .

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors have applied an anionic coating composition mainly composed of a pigment and an aqueous binder to a substrate and used it for ink jet recording. When producing a recording material, it has been found that by applying a cationic polymer to a substrate in advance, the ink absorption, resolution and water resistance of the obtained recording material can be significantly improved, leading to the present invention. Was.

That is, the present invention comprises a substrate suitable for ink-jet recording, a cationic polymer layer formed thereon, and an anionic coating layer mainly composed of a pigment and an aqueous binder formed on the cationic polymer layer. To provide a recording material for ink jet recording.

Further, the present invention provides a method for coating a substrate used in an ink jet recording method by coating a cationic polymer on a substrate and then coating an anionic coating composition mainly comprising a pigment and an aqueous binder. Provided is a method for manufacturing a recording material.

The present invention is characterized in that a cationic polymer is coated on a substrate in advance, and an anionic coating composition mainly comprising a pigment and an aqueous binder is coated on the substrate coated with the cationic polymer. When applied, the affinity between the cationic polymer and the anionic coating composition is considered to promote color setting, improve coverage, and make the coating layer porous, and the resulting recording The material shows significant improvements in ink absorption, resolution and water resistance. Hereinafter, the present invention will be described in more detail.

In the present invention, the substrate of the recording material may be any one suitable for ink jet recording, typically paper. Other examples include cloth and polyethylene terephthalate used for overhead projection. Various resin films such as a resin film can also be used. Such a substrate is first provided with a cationic polymer layer.

The cationic polymer used in the present invention is:
It refers to one in which the main polymer dissociates into cations in an aqueous medium, and typical cationic groups include primary, secondary and tertiary amino groups, and quaternary ammonium salts. Any cationic polymer can be used as long as it is such a cationic polymer. The type of the cationic polymer is not particularly limited. Examples of the cationic polymer preferably used in the present invention include the following.

A) a polyalkylenepolyamine obtained by dehydration-condensation of a polyalkylenepolyamine and a dibasic carboxylic acid; b) a polyalkylenepolyurea obtained by deammonification-condensation of a polyalkylenepolyamine and urea; c) a dealkylation of the polyalkylenepolyamide and urea D) a polyamino epoxy resin obtained by reacting an amino group-containing compound with epihalohydrin; e) a reaction product obtained by further reacting an aldehyde with any of the polymers a) to d) described above; f) A reaction product obtained by reacting any one of the polymers a) to d) with an alkylating agent; g) a ring-opening polymer of ethyleneimine; h) a cationic monomer having a polymerizable unsaturated bond is polymerized alone. Or a polymer copolymerized with another copolymerizable monomer; i) N-vinyl A homopolymer of a amide monomer or a hydrolyzate of a copolymer with another copolymerizable monomer; j) a Mannich reactant obtained by reacting a polymer having active hydrogen with ammonia, a primary amine or a secondary amine and formaldehyde. K) a reaction product of a polymer having active hydrogen with a cationizing agent; l) a reaction product of reacting a polymer having active hydrogen with ammonia or amines and epihalohydrin; m) chitosan obtained by hydrolyzing chitin; n) An aldehyde, epihalohydrin, a polymer having active hydrogen and any of the above-mentioned polymers a) to m)
A block copolymer reacted with a crosslinking agent such as polyisocyanate.

Specific examples of the starting compounds used in producing these various cationic polymers are shown below.

The polyalkylene polyamine used in the above a) and b) is a compound in which two primary amino groups and at least one secondary amino group are bonded via an alkylene, and is a compound of diethylene triamine, triethylene tetramine, tetraethylene Examples include ethylenepentamine and iminobispropylamine.

The dibasic carboxylic acid used in the above a) is a compound having two carboxyl groups, and is an aliphatic dicarboxylic acid such as succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid and fumaric acid. And aromatic dicarboxylic acids such as isophthalic acid and terephthalic acid, and mixtures thereof.

Examples of the amino group-containing compound used in d) include ammonia, various amines, polyalkylene polyamines, polyalkylene polyamides, polyalkylene polyureas, and polyamide polyureas.

The epihalohydrin used in the above d), l) and n) is exemplified by epichlorohydrin, epibromohydrin and the like.

Examples of the aldehyde used in the above e) and n) include alkyl aldehydes such as formaldehyde, acetaldehyde and propyl aldehyde, and alkyl dialdehydes such as glyoxal, propane dial and butane dial.

As the alkylating agent in the above f),
The following various types can be used. In the general formula R ¹ -X [wherein, R ¹ is a lower alkyl group (e.g., having about 1 to 6 carbon atoms), lower alkenyl groups (for example, about 2 to 6 carbon atoms),
Represents a benzyl group or a phenoxyethyl group, and X represents a halogen atom]. Preferred examples include, for example, methyl chloride, ethyl chloride, propyl chloride, allyl chloride, benzyl chloride, phenoxyethyl chloride, and bromides and iodides corresponding to these chlorides.

A dialkyl sulfite represented by the general formula (R ² O) ₂ SO _v [wherein R ² represents a lower alkyl group (for example, having about 1 to 6 carbon atoms) and v represents 1 or 2]; Dialkyl sulfate. Preferred examples include dimethyl sulphite, diethyl sulphite, dimethyl sulphate, diethyl sulphate and the like.

General formula

[0023]

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Wherein R ³ represents a hydrogen atom, a lower alkyl group (for example, about 1 to 6 carbon atoms), a hydroxy lower alkyl group (for example, about 1 to 6 carbon atoms) or a phenyl group; And its derivatives.
Preferred examples include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, glycidol and the like.

General formula

[0026]

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Wherein X represents a halogen atom and w represents 1, 2 or 3;
Preferred examples include epichlorohydrin, epibromohydrin and the like.

General formula HOCH ₂ (CH ₂ ) _w X wherein X represents a halogen atom, w is 1, 2 or 3
A monohalohydrin represented by the formula: Preferred examples include ethylene chlorohydrin, ethylene bromohydrin and the like.

General formula

[0030]

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Wherein X represents a halogen atom, one of Y and Z represents a halogen atom, and the other represents a hydroxyl group. Preferred examples are 1,3-
Dichloro-2-propanol, 2,3-dichloro-1-
And propanol.

The cationic monomer having a polymerizable unsaturated bond used in the above h) includes dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, dimethylamino Propyl (meth)
Examples thereof include acrylamide, quaternized products thereof, allylamine, diallylamine, triallylamine, vinylpyrrolidone, and diallyldimethylammonium salt.

Examples of the N-vinylamide monomer used in the above i) include vinylformamide and vinylacetamide.

Examples of the polymer having active hydrogen used in the above j), k), l) and n) include starches,
Examples thereof include proteins such as polyvinyl alcohol, polyacrylamide and casein, and methylcellulose.

Examples of the cationizing agent used in k) include, in addition to ethyleneimine, those represented by the following general formula.

[0036]

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[0037] [In these formulas, Q represents a divalent aliphatic group or an aromatic group, R ⁴ and R ⁵ each independently represents a lower alkyl group (for example, about 1 to 6 carbon atoms), R ⁶
Represents a hydrogen atom or a lower alkyl group (for example, having 1 to 6 carbon atoms)
A ⁻ represents an anion such as a halide ion or a sulfate ion, and L represents a leaving group such as a halogen atom, a sulfonate group or a sulfate group.]

In the above formula, examples of the divalent aliphatic group represented by Q include alkylene having about 1 to 10 carbon atoms, and this alkylene may be branched. You may have. Examples of the alkylene substituent include a hydroxyl group, an alkoxy group having about 1 to 6 carbon atoms, an alkanoyloxy group having about 1 to 6 carbon atoms, and a halogen atom. Examples of the divalent aromatic group represented by Q include substituted or unsubstituted phenylene. Examples of the phenylene substituent include those exemplified above as the alkylene substituent and about 1 to 6 carbon atoms. Alkyl group.

In the above formula, examples of the sulfonic ester group represented by L include a methanesulfonic acid residue (CH ₃ S
O ₂ O—), ethanesulfonic acid residue (C ₂ H ₅ SO ₂ O)
-), benzenesulfonic acid residue _{(C 6 H 5 SO 2 O-} ),
An alkyl or aryl sulfonic acid ester group such as a toluene sulfonic acid residue (CH ₃ C ₆ H ₄ SO ₂ O—) may be mentioned, and a sulfate ester group may be a sulfuric acid residue (HOSO ₂ O—). For example, a methyl sulfate residue (C
H ₃ OSO ₂ O-), ethyl sulfate residue (C ₂ H ₅ OSO ₂
O-), include esters of alkyl or aryl sulfates, such as phenyl acid residues _{(C 6 H 5 OSO 2 O-} ).

Among the various cationic polymers exemplified above, the colloid equivalent value at pH 3 is preferably 1 mg equivalent / g or more, and more preferably the colloid equivalent value is 2 mg equivalent / g or more. . In particular, the viscosity of a 50% by weight aqueous solution at 25 ° C. is 10%.
Those with cps or more are preferably used.

In addition to the cationic polymers, polyvalent metal salts such as sulfates and chlorides of aluminum, calcium, magnesium and the like are considered to have an interaction with the anionic coating composition intended in the present invention. However, these effects can not be obtained unless a large amount of coating on the substrate,
They are not suitable because they adversely affect the whiteness and storage stability of the substrate and the resulting recording material.

In the present invention, the above-mentioned cationic polymers can be used alone or in combination of two or more. At this time, surface paper strength enhancers such as starches, polyvinyl alcohols, and polyacrylamides having good compatibility, and various surface sizing agents may be used in combination. Furthermore, a fluorescent whitening agent, a preservative, an antifoaming agent, a lubricant, a water repellent, a water-proofing agent, a colorant, and the like can be blended as necessary while considering compatibility.

The cationic polymer is formed into a coating solution having an appropriate concentration in consideration of a coating amount and aptitude of a coating machine, and is coated on one side of a substrate by using a size press coater, a gate roll coater, a machine calender, a spray coater or the like. Alternatively, it is coated on both sides, but it is particularly preferable to use an on-machine coater. After that, by performing necessary drying,
A substrate coated with a cationic polymer in advance is obtained. The coating amount of the cationic polymer naturally varies depending on the kind of the cationic polymer to be used and the kind of the substrate, but is preferably about 0.01 to ² g / m ² per side.

In the present invention, an anionic coating composition containing a pigment and an aqueous binder is applied to a substrate coated with a cationic polymer thus obtained in advance by a conventional method, that is, a size press coater, a gate roll coater,
By coating with an air knife coater, a bill blade coater, a cast coater, a blade coater, a kiss roll coater, or the like, and performing a necessary drying treatment or smoothing treatment, a target recording material can be manufactured.

There are no particular restrictions on the composition or concentration of the coating composition containing the pigment and the aqueous binder used here, and the only condition is that the composition is anionic. Anionic coating compositions are those most widely used in paper coating and include anionic components in some form, such as pigments, aqueous binders, dispersants, etc., and the composition as a whole is anionic. Anything that indicates As an example, a white inorganic pigment or an organic synthetic white pigment,
There is a coating composition prepared by dispersing and slurrying using an anionic dispersant such as sodium tripolyphosphate or polyacrylate dispersant, and blending a water-soluble binder and / or a water-emulsified water-dispersed binder.

Examples of pigments include finely divided silica, clay,
Talc, diatomaceous earth, calcium carbonate, barium sulfate,
White pigments such as titanium oxide, zinc oxide, satin white, and aluminum silicate are exemplified. In addition, organic synthetic white pigments such as polystyrene resins and urea / formaldehyde resins can also be used.

Examples of the aqueous binder include water-soluble polymer binders such as starch, gelatin, casein, gum arabic, sodium alginate, carboxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, sodium polyacrylate, and polyacrylamide. In addition, synthetic resin emulsions such as synthetic rubber latex and ethylene vinyl acetate emulsion can be used.

The pigments serving as components of the anionic coating composition can be used alone or in combination of two or more, and the aqueous binders can be used alone or in combination of two or more. Can be used.
Further, various additives such as a dispersant, a preservative, a pH adjuster, an antifoaming agent, a surfactant, an optical brightener, and a lubricant can be added as necessary.

The recording material thus obtained according to the present invention and used in the ink jet recording method has various excellent and effective properties such as excellent ink absorption, high resolution and good water resistance. It becomes what has.

[0050]

The present invention will be described in more detail with reference to the following examples. The percentages in the examples represent% by weight unless otherwise specified. All viscosities are values at 25 ° C.

Examples 1 and 2 35 g (0.36 mol) of diallylamine, 34 g (0.24 mol) of a 50% aqueous acrylamide solution, 328 g of water, and 36.5 g of concentrated hydrochloric acid were placed in a four-necked flask equipped with a thermometer, a reflux condenser and a stirring rod. g (0.36 mol) was charged and heated to 70 ° C. under a nitrogen atmosphere. Then, 0.4 g of ammonium persulfate was added as an initiator and polymerized at 60 to 80 ° C. for 10 hours to obtain a cationic polymer A (aqueous solution) having a concentration of 15%, a pH of 3, and a viscosity of 440 cps. Rice basis weight 55.0 g
/ M ² of commercially available high-quality paper, the above-mentioned cationic polymer A was applied as a solid content of 0.34 g / m ² and 0.67 g / m ^{2, respectively,} and dried with a hot-air dryer at 120 ° C. for 30 seconds. Thus, a coated base paper coated with a cationic polymer was obtained. An anionic coating composition shown in Table 1 was applied to the coated base paper using a wire rod so as to have a coating amount of 10 g / m ^{2 on} one side, and was dried with a hot air dryer at 120 ° C. for 2 minutes. . Further, heat treatment was performed for 1 minute by a hot press machine to obtain a recording material.

[0052]

[Table 1]

Note) Mizukasil P-78D: Amorphous silica Sumireze Resin manufactured by Mizusawa Chemical Co., Ltd. DS-10: Polyacrylic acid pigment dispersant manufactured by Sumitomo Chemical Co., Ltd. PVA-117: manufactured by Kuraray Co., Ltd. Parts by weight of polyvinyl alcohol represent the solid content weight. The total solid content was 15.6%. The viscosity of the coating solution was 160 cps (B-type viscometer,
(60rpm)

Examples 3 and 4 The same reactor as used in Example 1 was charged with 160 g of water, and further 31 g (0.3 mol) of diethylenetriamine.
And 90 g (1 mol) of a 50% aqueous dimethylamine solution, 139 g (1.5 mol) of epichlorohydrin was added dropwise while maintaining the internal temperature at 60 ° C. or lower, and then 60 ° C.
The temperature was further raised to 60 to 80 ° C. for 6 hours. Next, 100 g of water was charged and cooled to 25 ° C., and the pH was adjusted to 3.5 with concentrated hydrochloric acid to obtain a cationic polymer B (aqueous solution) having a solid content of 40% and a viscosity of 150 cps.
On the same commercially available high quality paper as used in Example 1, the above cationic polymer B was coated to a solid content of 0.34 g / m ² and 0.67 g / m ² , respectively. The same processing was performed to obtain a recording material.

Comparative Example 1 A recording material was obtained in the same manner as in Example 1 except that the same commercially available high-quality paper as used in Example 1 was used and the cationic polymer was not applied. .

Evaluation Test Each recording material obtained as described above was subjected to the following tests. Table 2 shows the results.

Printing Ink jet recording was performed on a recording material using a color image printer IO-0700 manufactured by Sharp Corporation. For initial color development and water resistance, yellow, magenta,
Each color of cyan and black was solid-printed and evaluated by the following method. Regarding the resolution, characters were printed and evaluated by the method described below. Initial color development Color development density was measured with Macbeth densitometer (RD-915). Water resistance The sample after recording was immersed in water at 20 ° C. for 15 minutes, dried, measured for density with a Macbeth densitometer, and evaluated by the water resistance retention calculated by the following equation. Water resistance retention (%) = (Macbeth density after immersion drying / Macbeth density before immersion) × 100 Resolution The shape of dots and the bleeding of the ink were visually determined using a loupe. ◎ Excellent, ○ Good, △ Normal

Ink Absorption Using a color image printer IO-0700 manufactured by Sharp Co., Ltd., paper is fed immediately after ink-jet recording of the recording material, and the printing surface is pressed with a finger, and it is determined whether or not stains appear. did. ◎ Excellent, ○ Good, △ Normal air permeability Measured in accordance with J-TAPPI No.5.

[0059]

[Table 2]

[0060]

The recording material of the present invention has various excellent properties as an ink jet recording material, such as excellent ink absorbency when applied to an ink jet recording method, high resolution and excellent water resistance. Having.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-221591 (JP, A) JP-A-2-274587 (JP, A) JP-A-57-191084 (JP, A) JP-A 62-15984 146674 (JP, A) JP-A-62-140877 (JP, A) JP-A-61-188181 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/00

Claims (2)

(57) [Claims] 1. A substrate suitable for ink jet recording, comprising a cationic polymer layer formed thereon, and an anionic coating layer mainly composed of a pigment and an aqueous binder formed on the cationic polymer layer. Characteristic recording material for inkjet recording. 2. A recording medium for ink-jet recording, comprising coating a cationic polymer on a substrate suitable for ink-jet recording, and coating an anionic coating composition mainly comprising a pigment and an aqueous binder thereon. The method of manufacturing the material.