JPH11286170A - Ink jet recording medium for non-water soluble ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise the fixation of a coloring agent, and prevent adhesiveness from occurring on the surface by specifying a glass transition temperature of a polymer soluble in an isoparaffin hydrocarbon. SOLUTION: A polymer soluble in an isoparaffin hydrocarbon is coated on a tracing paper to produce an ink jet recording medium for non-water soluble ink suitable for ink jet recording. In this case, a glass transition temperature of the polymer soluble in the isoparaffin hydrocarbon is made not less than 25 deg.C, thereby obtaining a recording medium not suffering from the occurrence of an adhesiveness on the surface. For polymer used herein, there is given one containing as a constitutional unit an alkyl (meth)acrylate of an 8 or more C alkyl group, and the viscosity of a solution is set in the range of 10m Pa.s or more and 1000 m Pa.s or less at the time of being dissolved in the isoparaffin hydrocarbon by a density of 40 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording medium. More specifically, the present invention relates to an ink jet recording medium for a water-insoluble ink suitable for ink-jet recording using a water-insoluble ink in which a coloring agent is dissolved or dispersed in an isoparaffin-based hydrocarbon which is a non-aqueous solvent.

[0002]

2. Description of the Related Art Ink-jet recording is a technique for recording images and characters by causing minute droplets of ink to fly and adhere to a recording medium such as paper according to various operating principles. Ink-jet recording has features such as high speed, low noise, easy multi-coloring, great flexibility in recording patterns, and no need for development-fixing. It has various uses as a recording device for characters, figures, color images, etc. Are rapidly spreading.

Conventionally, in ink-jet recording, aqueous ink, that is, water or a mixed solvent of water and a hydrophilic solvent,
An ink in which a coloring agent such as a dye or a pigment is dispersed or dissolved has been used. However, the inkjet recording using the water-based ink has various problems caused by the printing portion of the recording medium absorbing and expanding the solvent in the ink. Such elongation of the recording medium is caused by hydrogen bonds between the fibers maintaining the mechanical strength of the support, which are cut by the solvent of the aqueous ink, particularly water, and adversely affects the conveyance of the recording medium in the printer. In addition, the accuracy of the relative positional relationship between the recording medium and the print head is deteriorated, and undesired phenomena such as a decrease in the dimensional accuracy of the obtained drawing and an unevenness in the image are caused.

To solve such a problem, Japanese Patent Laid-Open Publication No.
No. 0660, 57-10661,
JP-A-202324 and JP-A-5-331397 propose to use a water-insoluble ink in which a coloring agent is dissolved or dispersed in a non-aqueous solvent such as an isoparaffin-based hydrocarbon. According to these proposals, it is possible to perform ink jet recording with high dimensional accuracy and no unevenness in an image without any extension of the recording medium. In addition, the low viscosity and low surface tension of non-aqueous solvents make it possible to increase the drive frequency of the print head compared to inkjet recording using aqueous inks. It can be carried out.

As a recording medium used for ink-jet recording using such a water-insoluble ink, Japanese Patent Application Laid-Open No. 64-247 has been disclosed.
No. 85 proposes a recording medium comprising an oil-absorbing inorganic pigment, an organic pigment and an aqueous adhesive, and Japanese Patent Laid-Open No. 1-255580 proposes a recording medium comprising silica and an adhesive. . These recording media were so-called mat coat type recording media having a matte appearance on the recording surface, and had low light transmittance.

On the other hand, recording paper called tracing paper is used as a recording medium for drafting. This tracing paper is often used as a tool for tracing already drawn objects, for transmitting undistorted copies by positive exposure (so-called blue printing), and for drawing objects. There is a demand for the writing properties of pencils. As a method of manufacturing tracing paper, the pulp as a raw material is highly beaten to sufficiently promote fibrillation, and the inside of the pulp and the bond between the pulp are increased by providing sufficient intra- and inter-fiber bonds, thereby increasing the solidification. There are two methods: a method of eliminating the air interface (natural type) and a method of impregnating the paper with a resin to eliminate the air in the paper (impregnation type). As a natural type, for example, Japanese Patent Publication No. 52-31445, and as an impregnation type, for example, Japanese Patent Publication No. 56-6850.

As a drawing method on tracing paper, there are a direct drawing by a human hand using a pencil, a crow's mouth, a lot ring and the like, and a plotter as a CAD output. Previously, the above tools were used as writing instruments for plotters. However, due to recent advances in ink jet recording technology, the above-mentioned writing implements have been replaced by ink jet heads, and tracing paper has been required to have properties as ink jet recording paper. Such a recording medium has transparency and writability, and at the same time, has high definition of the recorded image, that is, the periphery of each dot is smooth and the outline is clear, and there is no repelling or flowing of ink. In addition, it is required that the image be excellent in storability, that is, the fixability of the colorant is high.

In order to meet such a demand, Japanese Patent Laid-Open No. 5-177 discloses an ink-jet recording using an aqueous ink.
No. 921 proposes a recording medium in which a surface size liquid containing a styrene-acrylic copolymer, a penetrant and a water-soluble polymer is coated on a support. In addition, Tokiko Sho 6
In JP-A-53958, a recording medium is proposed in which a coating layer made of a synthetic silica, an inorganic pigment, and a water-soluble polymer adhesive such as polyvinyl alcohol is formed on a support. According to these proposals, although it is possible to obtain an ink jet recording medium having transparency and writability and having a high absorbency with respect to an aqueous ink, even if recording is performed on these recording media with a water-insoluble ink, Since there is no affinity between the material forming the recording medium and the solvent or coloring agent contained in the ink, the distribution of the coloring agent in the recording medium becomes uneven and only a low image density can be obtained. To obtain a recorded image with high density, high definition, and excellent storability, for example, ink is repelled on the surface of the recording medium to cause unevenness, and the colorant easily falls off with a slight friction. Was absolutely impossible.

Further, Japanese Patent Application Laid-Open No. H8-324095 proposes an ink jet recording medium having a porous layer and a layer made of a resin which dissolves or swells in an ink solvent and is insoluble in water. I have. According to this proposal, it can be expected that an ink jet recording medium having excellent water resistance and high pigment fixability can be obtained. However, according to this proposal, depending on the properties and coating amount of the resin used for the resin layer, the writing properties are poor, or the surface of the ink jet recording medium develops adhesiveness, and when the ink jet recording medium is rolled, Blocking when printing and ink-jet recording media after printing are overlapped,
In addition, inconveniences such as defective conveyance of the inkjet recording medium in the recording apparatus may occur.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a recording medium having transparency and writability, high definition of a recorded image, and coloring for use in ink jet recording using such a water-insoluble ink. It is an object of the present invention to provide an ink jet recording medium for a water-insoluble ink, which has high fixability of an agent and does not cause tackiness on the surface.

[0011]

Means for Solving the Problems The inventor of the present invention has studied various types of ink jet recording media in order to solve the above problems, and by using the following structure, the object of the present invention, transmission, The present invention has made it possible to provide an ink jet recording medium for a water-insoluble ink, which has good properties and writability, has high definition of a recorded image, has high fixability of a colorant, and has no stickiness on its surface. That is, an ink jet recording medium for a water-insoluble ink obtained by coating a polymer soluble in an isoparaffinic hydrocarbon on a tracing paper, wherein the glass transition temperature of the polymer is 25 ° C. or more, The object of the present invention is to provide an ink-jet recording medium for a water-insoluble ink having transparency, writing properties, high definition of a recorded image, high fixability of a colorant, and no tackiness on the surface. Made it possible to provide.

In the present invention, the polymer soluble in the isoparaffinic hydrocarbon is once dissolved by the solvent in the ink after printing to capture the colorant therein, and then the solvent is dried to lose fluidity and color. By fixing the coloring agent inside, the colorant distribution inside the recording medium is made uniform, thereby improving the density and definition of the recorded image and improving the fixability of the coloring agent to the recording medium. doing.

[0013] Many polymers soluble in isoparaffinic solvents have a glass transition temperature lower than room temperature due to small intermolecular force. When such a polymer is contained near the surface of the recording medium, an undesired sticky feeling is likely to occur on the surface. However, according to the present invention, a polymer soluble in an isoparaffinic hydrocarbon has a glass transition temperature of 25 ° C.
By adopting the above, there is no need to separately take measures that may adversely affect the definition of the recorded image, such as providing an anti-adhesion layer, and it is possible to obtain a recording medium that does not have adhesiveness on the surface. it can. This is because even if the polymer soluble in the isoparaffinic hydrocarbon is continuously exposed on the outermost surface of the recording medium coated with the polymer soluble in the isoparaffinic hydrocarbon on the tracing paper, the glass transition temperature is still higher. Because it is above 25 ° C near room temperature,
In a normal use environment, the thermal motion of each segment in the polymer chain is suppressed and the polymer is in a hardened state, and thus it is presumed that tackiness is not exhibited on the surface.

When the polymer soluble in isoparaffinic hydrocarbon used in the present invention is dissolved in isoparaffinic hydrocarbon at a concentration of 40% by weight, the solution viscosity is 10%.
The range is preferably from mPa · s to 1000 mPa · s, more preferably from 20 mPa · s to 500 mPa · s. The viscosity is 10 mP
If it is less than a · s, the polymer will flow when dissolved in the solvent of the ink during printing, and the fixability of the ink will be insufficient. Further, when the viscosity exceeds 1000 mPa · s, the effect of the present invention is such that the penetration rate of the solvent into the polymer is slow, and the capture of the colorant into the polymer is delayed and the fixation of the colorant becomes poor. Is not fully exhibited. The above viscosity measurement is preferably performed using the same brand of isoparaffinic hydrocarbon solvent as that used for the ink to be used.However, since the difference in viscosity due to the difference in solvent is usually small, other brands are substituted. You may. Further, the temperature at which the viscosity measurement is performed is preferably the temperature of the printing unit of a printer using the present recording medium,
If this temperature is unknown, room temperature may be used. Also,
At the time of printing, since a large shearing force is not applied to the inside of the recording medium, it is preferable that the above-mentioned viscosity measurement is performed on a solution that has been left still for a while by using a method with the smallest possible shearing force.

The coating amount of the polymer soluble in the isoparaffinic hydrocarbon in the water-insoluble ink jet recording medium of the present invention is preferably in the range of 0.3 g / m ^{2 to} 10 g / m ² , 1 g / m ² or more and 8 g / m ²
More preferably, it is in the following range. If the coating amount is less than this range, the distribution of the coloring agent becomes non-uniform, and the definition and density of the recorded image are reduced, or the fixability is insufficient. If the coating amount is larger than this range, the ink absorption speed becomes insufficient,
Undesirable unevenness occurs in the image, and the writing property becomes poor.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The polymer soluble in isoparaffinic hydrocarbons in the present invention refers to a polymer which forms a uniform phase by mixing with isoparaffinic hydrocarbons at an arbitrary ratio at room temperature. Various polymers can be used. For example, poly (1,3-diene) such as polybutadiene / polyisoprene, polyalkyl (C ₄ or more) vinyl ether, polyalkyl (C ₄
Or more) vinyl carboxylate, polyalkyl (C ₄ or more) (meth)
Acrylate, polyalkyl (C ₆ or more) (meth) acrylamide, polyalkylene (C ₄ or more), polyoxyalkylene (C ₄ or more), polydimethylsiloxane, petroleum resin (C
₅ based, C ₉ series), novolac resins, polymers such as gutta percha, and a copolymer composed of the monomers constituting these polymers can be used in isoparaffin hydrocarbon in the present invention as soluble polymers.

These polymers may be subjected to various modifications as long as the solubility in isoparaffinic hydrocarbons is not lost. For example, lower alkyl vinyl ether, lower alkyl vinyl carboxylate, lower alkyl (meth) acrylate, (meth) acrylic acid, tetrahydrofurfuryl (meth) acrylate, alkyloxyethyl (meth) acrylate, dialkylaminoethyl (meth)
Acrylate, lower alkyl (meth) acrylamide,
(Meth) acrylamide, lower (di) alkyl (meth) acrylamide, diacetone (meth) acrylamide, 2- (meth) acrylamide-2-methylpropanesulfonic acid,
By copolymerizing monomers such as dialkylaminopropyl (meth) acrylamide and styrene with the monomers constituting the above-mentioned polymer, the polymer soluble in the isoparaffinic hydrocarbon of the present invention can be modified.

The ink-jet recording medium for a water-insoluble ink of the present invention has a glass transition temperature of less than 25 ° C. in addition to a polymer soluble in isoparaffinic hydrocarbon having a glass transition temperature of 25 ° C. or more. A polymer that is soluble in isoparaffinic hydrocarbons or a polymer that is insoluble in isoparaffinic hydrocarbons is mixed and used within a range that does not impair the fineness of the recorded image, the fixability of the colorant, and the absence of tackiness on the surface. be able to.

As a polymer soluble in an isoparaffinic hydrocarbon used in the ink jet recording medium for a water-insoluble ink of the present invention, an alkyl group having 8 or more carbon atoms
The use of a compound containing (meth) acrylate as a constitutional unit is preferable because the density and definition of a recorded image can be particularly increased. This is presumed to be because the structure in which the higher alkyl group, which has a high affinity for isoparaffinic hydrocarbons, is linked to the polymer main chain via an ester bond having an appropriate polarity captures the colorant particularly efficiently. However, details of the mechanism of action are not clear.

In the case where the polymer containing isobornyl (meth) acrylate as a structural unit is used as the polymer soluble in the isoparaffinic hydrocarbon used in the ink jet recording medium for the water-insoluble ink of the present invention, the pigment is used as a colorant for the ink. Particularly, it is particularly preferably used because it is possible to improve the fixability to the recording medium without lowering the definition of the obtained image. This is presumed to be because the structure having a high affinity for the ink solvent and having a bulky and rigid substituent has an ink-capturing action and firmly fixes the once-captured pigment. The details are not clear.

These structures include, for example, polybutadiene,
Compared to polymers such as polyisoprene, they do not have unsaturated bonds in the structure, so they are oxidized by oxygen in the air during storage of the recording medium to form polar groups, and their solubility in isoparaffinic solvents is reduced. There is also an advantage that the phenomenon that the effect of the present invention is hardly exerted due to the decrease is hardly caused.

The glass transition temperature of the polymer soluble in the isoparaffinic hydrocarbon used in the present invention is POLYMER
HANDBOOK THIRD EDITION (JOHN WILEY &SONS; 1989)
The glass transition temperature of the copolymer is calculated from Fox equation (Introduction to Polymer Chemistry, 2nd ed .; 1981; P. 172), cited from Chapter VI, pages 209 to 278.
Was calculated.

As a method for applying a polymer soluble in isoparaffinic hydrocarbon to the ink-jet recording medium for water-insoluble ink of the present invention, an aqueous dispersion of fine particles, which is applied by dissolving in an appropriate organic solvent, so-called latex Various methods can be used, such as applying as a precursor, applying a monomer or oligomer as a precursor, and then irradiating with ultraviolet rays or an electron beam to polymerize. As a coating method, a die coater, a roll coater, an air knife coater, a blade coater, a rod coater, a bar coater, a gravure coater, a curtain coater, a lip coater, or the like can be used.

According to the present invention, in order to obtain a recorded image having high density and high definition, it is preferable that a polymer soluble in isoparaffinic hydrocarbon is contained nearer the surface of the recording medium. In the case where the polymer is contained unevenly near the back surface side of the recording medium, the colorant in the ink penetrates to the deep part, which is higher than the case where the polymer is contained closer to the front surface side of the recording medium. No image density can be obtained, and furthermore, the outline of the recorded image becomes unclear and the definition of the recorded image decreases.

In the present invention, an inorganic pigment or an organic pigment such as colloidal silica or alumina sol is coated on a tracing paper as an ink receiving layer together with a binder on the tracing paper within a range that does not impair the permeability in order to enhance the absorbability of the ink solvent. May be set. However, when components other than the polymer soluble in these isoparaffinic hydrocarbons are coated, in order to obtain an ink jet recording medium for a water-insoluble ink having a high density and high definition of a recorded image according to the present invention, isoparaffin is required. The polymer soluble in the system hydrocarbon is preferably applied separately from the other components constituting the ink receiving layer, and is particularly preferably applied alone after the other components constituting the ink receiving layer. Is preferred. Specifically, it is more preferable to provide a layer of a component other than the polymer soluble in the isoparaffinic hydrocarbon such as a pigment on the tracing paper, and then apply the polymer soluble in the isoparaffinic hydrocarbon. That is, it is preferable that 60% by weight or more of the active ingredient in the coating composition in the coating step of the polymer is the polymer or a precursor thereof. It is particularly preferred that the composition is applied alone after the application of the above component. This is because, when the polymer is applied simultaneously with other components, the structure is surrounded by other components having no affinity for the solvent of the ink, and the effect of including the polymer in the recording medium is sufficiently improved. This is because it becomes difficult to be exhibited. Further, when the coating composition of the polymer is applied last, the polymer is concentrated in the ink-receiving layer at a location where ink is most likely to penetrate, and the effect of including the polymer is obtained. Is more preferably exerted.

The transmissivity referred to in the present invention refers to the light transmissivity required when tracing an already drawn image or when obtaining a copy without distortion by a positive exposure method.
Refers to the same meaning as transparency.

As the tracing paper used for the ink jet recording medium for a water-insoluble ink of the present invention, a natural type tracing paper is more preferably used. The pulp used in the tracing paper of the present invention is obtained by advanced beating until a sufficient internal fibrillation and an external fibrillation occur by advanced viscous beating. Since the degree of progress of beating cannot be measured by the ordinary method for evaluating drainage, the pulp of the present invention is JIS
According to the Canadian standard freeness specified in P8121, 0.5 g of absolutely dry pulp was diluted to 1000 ml, and beaten to 100 ml or less at a modified Canadian freeness in which a 80-mesh plain-woven bronze wire was used. Use the advanced one. Using highly beaten pulp in this way, through sufficient dewatering on the wire with a paper machine and sufficient water squeezing with a press, while controlling shrinkage due to drying with a dryer, avoid rapid drying Dry carefully,
A natural type tracing paper can be obtained.

The pulp used in the present invention is LBK.
P, NBKP, LBSP, NBSP, and various bleached non-wood pulp. In use, they may be mixed and used at a ratio according to several purposes. The pulp used in the present invention is beaten by a beating machine such as a double disc refiner, a deluxe finer, or a jordan until the freeness in Canada is reduced to 100 ml or less as described above. When making paper using the beaten pulp in the present invention, a paper machine such as a fourdrinier, a circular knit, a twin wire, an on-top, or a hybrid can be used.

The thickness of the tracing paper used in the present invention does not need to be particularly limited, but is preferably about 30 to 200 μm from the viewpoint of the handling property and the suitability for paper passing of the printer.

The tracing paper used in the present invention may be a laminated tracing paper. Laminated type tracing paper is obtained by laminating natural type tracing paper and a transparent resin film such as polyethylene terephthalate, and applying the polymer soluble in the isoparaffinic hydrocarbon of the present invention to the tracing paper side. You can do it. Examples of the bonding method include a dry lamination method, an ultraviolet curing method, and an electron beam curing method.

In the drying method used in the present invention, it is difficult to control wrinkles and curl only by drying using an air dryer. Therefore, a drying facility provided with a drum dryer may be used. Further, as a final curl adjustment method, equipment for spraying steam and a calendar may be provided. In some cases, a method of applying water or an aqueous coating solution to the back surface can also be selected.

The ink-jet recording medium for a water-insoluble ink of the present invention is provided with an anchor coat layer, if necessary, in order to improve the adhesion between a polymer soluble in isoparaffinic hydrocarbon and tracing paper. You may. Further, a blocking-resistant layer or the like for further suppressing surface blocking may be provided. Further, a back coat layer can be provided for the purpose of improving transportability in the printer, suppressing curl generated after printing, and the like.

[0033]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples. In this example, parts and% represent parts by weight and% by weight, respectively, unless otherwise specified.

Synthesis Example 1 In a four-necked flask equipped with a stirrer, stearyl methacrylate (SMA, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 10 was added as a monomer.
0 parts and 100 parts of xylene as a solvent were charged and heated to 75 ° C. in a water bath while passing nitrogen. Here, 4 parts of 2,2'-azobis (2-methylbutyronitrile) (V-59, manufactured by Wako Pure Chemical Industries, Ltd.) was added as a polymerization initiator, and the mixture was heated at 75 ° C.
Time was maintained. Thereafter, the mixture is heated to 90 ° C.
Time was maintained. Finally, 50 parts of xylene was added to prepare Synthesis Example 1.
Was obtained. The glass transition temperature of this polymer calculated by Fox's formula was 38 ° C. The polymer solution was spread thinly on a glass Petri dish and dried at 80 ° C., and then the dried film was dissolved in a 4-fold weight isoparaffin-based hydrocarbon solvent (Isopor G, manufactured by Exxon Chemical). The polymer solution was evaporated to dryness using a rotary evaporator, then dissolved in Isopar G, adjusted to a concentration of 40%, allowed to stand at 25 ° C. for 1 hour, and the viscosity was measured using a Brookfield viscometer ( It was 40 mPa · s when measured with a Tokyo Keiki BL model, No. 1 rotor, 12 revolutions per minute).

Synthetic Examples 2 to 4 and Comparative Synthetic Examples 1 to 3 Synthetic Examples 1 to 4 except that the monomers shown in Table 1 were used instead of 100 parts of stearyl methacrylate.
In the same manner as in the above, polymer solutions of Synthesis Examples 2 to 4 and Comparative Synthesis Examples 1 to 3 were obtained. Further, for each polymer solution, the solubility in Isopar G and the viscosity of the 40% Isopar G solution were measured by the same operation as in Synthesis Example 1.

[0036]

[Table 1]

Synthesis Example 5 In a four-necked flask equipped with an agitator, 100 parts of stearyl acrylate (light acrylate SA manufactured by Kyoeisha Chemical Co., Ltd.) and 150 parts of xylene as a solvent were charged. Heated to ° C. Here, 2,2'-azobis (2
-Methylbutyronitrile) (1 part of Wako Pure Chemical Industries, Ltd. V-59) was added, and the mixture was maintained at 75 ° C for 2 hours. Thereafter, the mixture was heated to 90 ° C. and maintained at this temperature for 2 hours to obtain a polymer solution of Synthesis Example 5. The glass transition temperature of this polymer calculated by Fox's formula was 39 ° C. The solubility of this polymer solution in Isopar G was examined by the same operation as in Synthesis Example 1, and the polymer was dissolved. The viscosity of the 40% Isopar G solution was 35 mPa · s.

Synthesis Examples 6 to 8 and Comparative Synthesis Example 4 Synthesis Examples 6 to 8 were prepared in the same manner as in Synthesis Example 5 except that the monomers shown in Table 2 were used instead of 100 parts of stearyl acrylate. A polymer solution of Comparative Synthesis Example 4 was obtained. For each polymer solution, the solubility in Isopar G and the
The viscosity of the% Isopar G solution was measured.

[0039]

[Table 2]

SYNTHESIS EXAMPLES 9-12 Synthesis examples were prepared in the same manner as in Synthesis example 1 except that 2,2'-azobis (2-methylbutyronitrile) as a polymerization initiator was added in the amount shown in Table 3. 9-12 polymer solutions were obtained. Further, for each polymer solution, the viscosity of the 40% Isopar G solution was measured by the same operation as in Synthesis Example 1.

[0041]

[Table 3]

Synthesis Example 13 A four-necked flask equipped with an agitator was charged with 150 parts of xylene as a solvent, and charged in a water bath while passing nitrogen.
Heated to 5 ° C. Here, 2,2 'is used as a polymerization initiator.
6 parts of azobis (2-methylbutyronitrile) are added,
100 parts of stearyl methacrylate was added dropwise over 4 hours,
After the completion of the dropwise addition, the temperature was further maintained at 75 ° C. for 4 hours. After this 90
C., and maintained at this temperature for 2 hours to obtain a polymer solution of Synthesis Example 13. The solubility of this polymer solution in Isopar G was examined by the same operation as in Synthesis Example 1 and the polymer was dissolved. The viscosity of the 40% Isopar G solution was measured and found to be 8 mPa · s.

Synthesis Example 14 A four-necked flask equipped with an agitator was charged with 100 parts of stearyl methacrylate as a monomer and 100 parts of xylene as a solvent.
Until heated. Here, 0.1 part of 2,2'-azobis (2-methylbutyronitrile) was added as a polymerization initiator,
Additional 0.1 parts every 4 hours for 20 hours 75
C. was maintained. Thereafter, the mixture is heated to 90 ° C.
Time was maintained. Finally, 50 parts of xylene was added to prepare Synthesis Example 1.
4 was obtained. About this polymer solution,
When the solubility for Isopar G was examined by the same operation as in Synthesis Example 1, it was dissolved, and the viscosity of the 40% Isopar G solution was measured to be 1320 mPa · s.

Example 1 To 10 parts of the polymer solution prepared in Synthesis Example 1 was added toluene 2
A coating solution was prepared by diluting with 0 part. This coating solution was applied on a natural type tracing paper (DX tracing paper N75 manufactured by Mitsubishi Paper Mills, transparency: 72.3%) using a wire bar so that the coating amount after drying was 4 g / m ^2. This was applied to produce the ink jet recording medium for water-insoluble ink of Example 1.

Comparative Example 1 Natural type tracing paper (DX tracing paper N7 manufactured by Mitsubishi Paper Mills)
5: Transparency 72.3%) was used as it was as Comparative Example 1.

Examples 2 to 10 and Comparative Examples 2 to 5 The polymer solutions of Example 1 were replaced with Synthesis Example 1, Synthesis Example 3, Synthesis Example 4, Synthesis Example 5, Synthesis Example 6, and Synthesis Example 1, respectively. 7, Synthesis Example 8, a 40% xylene solution of a petroleum resin (Escolets 5380 manufactured by Tonex): Tg = 85 ° C., and a hydrogenated petroleum resin (Rigalets 1094 manufactured by Hercules):
(Tg = 38 ° C.), except that a 40% xylene solution was used.
Inkjet recording media for water-insoluble inks of 6, 7, 8, 9 and 10 were produced. The solubility of the above petroleum resin and hydrogenated petroleum resin in Isopar G was examined in the same manner as in Synthesis Example 1, and the petroleum resin was dissolved. Further, the same procedure as in Example 1 was performed except that the polymer solution of Example 1 was replaced with Comparative Synthetic Example 1, Comparative Synthetic Example 2, Comparative Synthetic Example 3, and Comparative Synthetic Example 4 instead of Synthetic Example 1. , Comparative Examples 2, 3, 4,
And 5 were prepared.

Ink Preparation Example A To 70 parts of Isopar G, 15 parts of butyl benzoate and 5 parts of polyoxyethylene laurylamine (oxyethylene addition number: 7; Newcol 407 manufactured by Nippon Emulsifier) were added and stirred. Here, an oil-soluble black dye C.I. I. Sol
Vent Black (10 parts) was added, and the mixture was sufficiently stirred and dissolved to prepare an ink of Ink Preparation Example A in which an oil-soluble dye was dissolved in a hydrocarbon solvent.

Ink Preparation Example B 16 parts of a turpentine oil derivative resin (YS Polystar T80 manufactured by Yasuhara Chemical) was heated to 100 ° C., and 8 parts of a black pigment (CI Pigment Black 7) was added thereto. Kneaded thoroughly. Then, the kneaded product was cooled to room temperature and pulverized by a jet mill to obtain a surface-treated pigment. Dispersant (Nikkor TO-106 manufactured by Nippon Surfactant) 2 in 74 parts of Isopar G
Was dissolved, and the surface-treated pigment was added thereto and dispersed sufficiently by a ball mill to prepare an ink of Ink Preparation Example B in which colored particles were dispersed in a hydrocarbon solvent.

Evaluation The evaluation method for each item is shown below.

<Fixing Property> An excessive amount of the ink of Preparation Example A was dropped on each of the ink-jet recording media for water-insoluble inks, and the ink droplets were immediately developed using a wire bar having a liquid film thickness of 10 μm. For 1 hour to dry. After that, the surface of the ink developing section was rubbed once with an index finger in one direction, and the colorant that did not spread around the original developing section (good fixability) was evaluated as “good”. The sample with no apparent change in the density was evaluated as Δ, and the sample with the original density of the developed portion lowered (defective fixing property) was evaluated as x.

<Adhesiveness> In the above evaluation of the fixability, those with no sticky feeling at the fingertip were evaluated as 、, those with weak adhesiveness as Δ, and those with strong adhesiveness as X. did.

<Shape> Each ink-jet recording medium for water-insoluble ink was kept horizontal, and a 1 μL-volume micro-syringe (Hamilton 7) equipped with a needle having an inner diameter of 0.15 mm was used.
101), one drop of the ink of Ink Preparation Example A was dropped, and left to dry at room temperature for 1 hour. An image obtained by observing the surface of the ink dropping portion with a microscope (100 ×) was obtained using LUZ.
Analyze with an EX5000 image analyzer (Nireco)
The shape factor calculated by Equation 1 was obtained. A smaller (closer to 100) value of the shape factor means a higher roundness, and a high-definition image without blur or omission when printed by a printer can be obtained. When the shape factor was less than 150, it was evaluated as 、, when it was 150 or more and less than 200, it was evaluated as Δ, and when it was 200 or more, it was evaluated as x.

<Ink Absorption Rate> Each ink-jet recording medium for a water-insoluble ink was tilted at 60 °, and one drop of the ink of Ink Preparation Example A was dropped using the same microsyringe as described above. The maximum diameter in the inclined direction and the maximum diameter in the horizontal direction of the ink dropping portion were measured, and the maximum diameter ratio represented by Expression 2 was obtained. A smaller value (closer to 1) means that the ink did not flow down the surface of the recording medium between the time it came in contact with the surface of the recording medium and was absorbed, that is, the faster the ink was absorbed. Thus, an image without unevenness can be obtained when printing with a printer. When the maximum diameter ratio was less than 3, it was evaluated as ○, when it was 3 or more but less than 4, and when it was 4 or more, it was evaluated as x.

<Transparency> The opacity of each water-insoluble ink jet recording medium was measured in accordance with the method B of JIS P8138, and the value obtained by subtracting the opacity from 100% was defined as the transparency. The higher the value of this transparency, the more
It means that permeability is good.

<Writability> Characters were written on each ink-jet recording medium for water-insoluble ink using a 2H pencil, and the characters which were written clearly and densely and were sufficiently readable were ○. Δ, those that could not be read because they were too thin were marked X.

[Formula 1] Shape factor = (contour length of ink dropping portion) ² ÷ (4π × area of ink dropping portion) × 100

[Equation 2] Maximum diameter ratio = Maximum diameter in inclined direction / Maximum diameter in horizontal direction

Table 4 shows the evaluation results. The transparency of each of the ink-jet recording media for water-insoluble inks was 70% or more, and the transparency was good.

[0059]

[Table 4]

Example 11 Ten parts of the polymer solution prepared in Synthesis Example 6 was mixed with toluene 2
A coating solution was prepared by diluting with 0 part. This coating solution was used in Example 1
The same tracing paper as that described above was applied using a wire bar so that the coating amount after drying was 3 g / m ² , to produce an ink jet recording medium for a water-insoluble ink of Example 11.

Examples 12 to 17 Each of the coating amounts after drying in Example 11 was 0.2 g / m ² ,
Example 1 except that 0.4 g / m ² , 1 g / m ² , 6 g / m ² , 9 g / m ² and 12 g / m ² were used.
In the same manner as in Example 1, Examples 12, 13, 14, 15, 1
Inkjet recording media for water-insoluble inks Nos. 6 and 17 were produced.

Table 5 shows the evaluation results. The transparency of each of the ink-jet recording media for water-insoluble inks was 70% or more, and the transparency was good.

[0063]

[Table 5]

Example 18 Ten parts of the polymer solution prepared in Synthesis Example 1 was
A coating solution was prepared by diluting with 0 part. This coating solution was used in Example 1
Using a wire bar, the same tracing paper as in Example 1 was applied so that the coating amount after drying was 2 g / m ² , to produce an ink jet recording medium for water-insoluble ink of Example 18.

Examples 19 to 24 The polymer solutions of Example 18 were replaced with Synthesis Example 9, Synthesis Example 10, Synthesis Example 11, Synthesis Example 12, Synthesis Example 13, and Synthesis Example 14, respectively. Other than Example 18
In the same manner as in Examples 19, 20, 21, 22, 23,
And 24 ink-jet recording media for water-insoluble inks were produced.

Table 6 shows the results of these evaluations. The transparency of each of the ink-jet recording media for water-insoluble inks was 70% or more, and the transparency was good.

[0067]

[Table 6]

Examples 25 to 34 Evaluations of fixability and shape were carried out in the same manner as in Examples 1 to 10, except that Ink Preparation Example B was used instead of Ink Preparation Example A. went. Table 7 shows the evaluation results.

[0069]

[Table 7]

[0070]

According to the present invention, there is provided an ink jet recording medium for a water-insoluble ink obtained by coating a polymer soluble in isoparaffinic hydrocarbon on tracing paper, wherein the polymer has a glass transition temperature of 25. By having a configuration that is not less than ℃, it has transparency and writability,
For water-insoluble inks that have high definition of recorded images, fixability of colorant, and no stickiness on the surface when used for inkjet recording with water-insoluble inks using isoparaffinic hydrocarbons as solvents It has become possible to provide an inkjet recording medium. That is, as is apparent from a comparison between Examples 1 to 10 and Comparative Examples 1 to 5, an ink jet recording medium for a water-insoluble ink in which a polymer soluble in an isoparaffinic hydrocarbon is coated on tracing paper. The polymer has a glass transition temperature of 25 ° C. or more, has transparency and writability, and is used for inkjet recording using a water-insoluble ink containing isoparaffinic hydrocarbon as a solvent. High recording image definition, colorant fixability,
It has become possible to provide an ink jet recording medium for a water-insoluble ink that has no tackiness on the surface.

The polymer soluble in isoparaffinic hydrocarbons in the ink jet recording medium for water-insoluble inks of the present invention may be an alkyl group having 8 or more carbon atoms.
The use of an ink containing (meth) acrylate as a structural unit makes it possible to provide an ink jet recording medium for a water-insoluble ink having higher definition of a recorded image. That is, Examples 1, 3 to 5, 7, 8 and Examples 9, 10 and Examples 25, 27 to 29, 31, 32
As is clear from a comparison between Examples 26, 30, 33 and 34, the polymer soluble in the isoparaffinic hydrocarbon in the ink jet recording medium for water-insoluble ink of the present invention has an alkyl group having 8 carbon atoms. Alkyl over
The use of an ink containing (meth) acrylate as a structural unit makes it possible to provide an ink jet recording medium for a water-insoluble ink having higher definition of a recorded image.

By using a polymer having isobornyl (meth) acrylate as a structural unit as a polymer soluble in isoparaffinic hydrocarbon in the ink jet recording medium for water-insoluble ink of the present invention, a pigment can be used as a colorant for the ink. In such a case, it has become possible to further improve the fixability to the recording medium. That is, Examples 26 to 28, 30 to 32 and Examples 25, 29, 33,
As is clear from comparison with No. 34, as a polymer soluble in isoparaffinic hydrocarbon in the ink-jet recording medium for water-insoluble ink of the present invention, by using a polymer having isobornyl (meth) acrylate as a structural unit. In the case where a pigment is used as a colorant for the ink, it is possible to further improve the fixability to the recording medium.

When the polymer soluble in isoparaffinic hydrocarbon used in the present invention is dissolved in isoparaffinic hydrocarbon at a concentration of 40% by weight, the solution viscosity is 10 m.
By setting the range of Pa · s to 1000 mPa · s, it was possible to obtain an ink jet recording medium for a water-insoluble ink having particularly excellent fixability of a colorant. That is, as is clear from comparison of Examples 18 to 22 with Examples 23 and 24, particularly Examples 18, 20, and 21 and Examples 23 and 24, the compounds are soluble in the isoparaffinic hydrocarbon used in the present invention. By setting the solution viscosity of the polymer in the range of 10 mPa · s or more and 1000 mPa · s or less when the polymer is dissolved in isoparaffinic hydrocarbon at a concentration of 40% by weight, the non-aqueous solution particularly excellent in fixability of the colorant is obtained. Thus, an ink jet recording medium for hydrophilic ink was obtained.

The amount of the polymer soluble in the isoparaffinic hydrocarbon in the ink jet recording medium for water-insoluble ink of the present invention is set in the range of 0.3 g / m ² or more and 10 g / m ² or less. It has become possible to provide an ink jet recording medium for a water-insoluble ink which has good properties, good fixability of a colorant, good fineness and can obtain a recorded image with less unevenness. That is, the first embodiment
1, 13 to 16 and Examples 12 and 17, especially Example 1
As is clear from comparison between Examples 1, 14 and 15 with Examples 12 and 17, the coating amount of the polymer soluble in the isoparaffinic hydrocarbon was in the range of 0.3 g / m ^{2 to} 10 g / m ^2. By doing so, it is possible to provide an ink jet recording medium for a water-insoluble ink that has good writing properties, good fixability of a colorant, good definition, and a recorded image with less unevenness. Was.

Claims (5)

[Claims] 1. An ink jet recording medium for a water-insoluble ink obtained by coating a polymer soluble in isoparaffinic hydrocarbon on tracing paper, wherein the polymer has a glass transition temperature of 25 ° C. or higher. Ink jet recording medium for water-insoluble ink. 2. The ink jet recording medium for a water-insoluble ink according to claim 1, wherein the polymer soluble in the isoparaffinic hydrocarbon contains an alkyl (meth) acrylate having an alkyl group having 8 or more carbon atoms as a constituent unit. 3. The ink jet recording medium for a water-insoluble ink according to claim 1, wherein the polymer soluble in isoparaffinic hydrocarbon contains isobornyl (meth) acrylate as a constituent unit. 4. When the polymer soluble in isoparaffinic hydrocarbon is dissolved in isoparaffinic hydrocarbon at a concentration of 40% by weight, the viscosity of the solution is 10 mPa · s or more and 100 mPa · s or more.
The inkjet recording medium for a water-insoluble ink according to any one of claims 1 to 3, which has a range of 0 mPa · s or less. 5. The water-insoluble ink according to claim 1, wherein the coating amount of the polymer soluble in the isoparaffinic hydrocarbon is in a range of 0.3 g / m ^{2 to} 10 g / m ^2. Ink jet recording medium.