JPH01222985A - Ink jet recording sheet - Google Patents

Abstract

PURPOSE:To improve irregularities in a uniform printing area, to enhance a light-transmittance, and to make a sheet available as an OHP original, by incorporating hydrophobic fine particles in an ink accepting surface. CONSTITUTION:An ink absorbing layer is formed on a transparent substrate, and hydrophobic fine particles are incorporated in ink accepting surface. As the hydrophobic fine particles, hydrophobic oil drips or hydrophobic solid fine particles can be used with a suitable particle size of approximately 0.01-10mum. An oily substance used for the hydrophobic oil drips is desirably a high-boiling organic liquid with a boiling point of 140 deg.C or more. As the hydrophobic solid fine particles, fine particles of solid fluorine compound resin etc. can be used. To form the water-ink absorbing layer on the transparent substrate, a mixture of a water-soluble binder and the hydrophobic fine particles is dissolved or dispersed in a water or a suitable organic solvent to prepare a coating liquid, and this coating liquid is applied on the transparent substrate by a roll coating method etc. and dried.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an inkjet recording sheet using water-based ink, and in particular an inkjet recording sheet with improved image unevenness in uniformly drawn areas and excellent light transparency. It is related to. Furthermore, the present invention relates to an inkjet recording sheet suitable for use as a manuscript for OHP (overhead projector) and the like.

(Prior Art) Inkjet recording is noiseless and enables high-speed recording, and has been adopted in terminal printers and has become rapidly popular in recent years. Furthermore, by using a large number of ink nozzles, it is easy to perform multicolor recording, and multicolor inkjet recording using various inkjet recording methods is being considered.

In recent years, in particular, the use of inkjet printers, which can quickly and accurately form complex images, has been attracting attention as a device for creating hard copies of computer-generated image information such as characters and various figures. Furthermore, the image information created by the computer was recorded on a transparent recording sheet using an inkjet printer, and this was recorded as 01 (
There is also an increasing demand for use as manuscripts for publications such as P.

For inkjet recording, water-based inks are mainly used for safety and recording properties, and polyhydric alcohols are added to prevent nozzle clogging and improve ejection properties. It is often done.

Conventionally, the recording sheet used in this inkjet recording method is a recording sheet made by providing a porous ink absorbing layer on a support called ordinary paper or inkjet recording paper. It's here.

However, there are several problems when using these conventional recording sheets as OHP originals. That is, these recording sheets usually have poor light transmittance, and even in the case of transparent recording sheets, their aqueous ink receptivity is poor.

That is, most conventional recording sheets use a method in which a porous ink absorbing layer is provided on the surface, and ink is absorbed into the porous voids to fix the ink. Therefore, even if a transparent support is used, there is a problem that the porous ink absorbing layer deteriorates light transmittance.

In addition, when the surface of the ink absorption layer is non-porous, the light transmittance is improved, but the aqueous ink receptivity is poor, so the image recording condensate ink remains on the surface of the recording sheet for a long time and dries. There was a problem that the fixing time was long.

In order to solve these problems, many recording sheets have been proposed in which a transparent ink absorbing layer with high aqueous ink receptivity is provided on a transparent support.

For example, JP-A-60-168651 uses polyvinyl alcohol and polyacrylic acid-based water-soluble polymers, JP-A-60-262,685 uses hydroxyethyl cellulose, and JP-A 61-181,679 uses carboxymethyl cellulose. The use of a mixture of polyethylene oxide and JP-A-61-193879 proposes the use of a mixture of water-soluble cellulose and polyvinylpyrrolidone.

(Problems to be Solved by the Invention) The recording sheets described in these patents are characterized by excellent light transmittance and high aqueous ink receptivity.
Immediately after image recording, the ink absorbency is still insufficient, resulting in the problem of image unevenness (particularly image unevenness in uniformly drawn areas).

That is, the minute droplets of the aqueous ink liquid are not absorbed by the ink absorbing layer the moment they adhere to the surface of the recording sheet, and it takes at least several seconds to several minutes for most of them to be absorbed.

During this time, the fine ink droplets coalesce to form large droplets, causing a problem in that areas that should originally appear uniform (uniformly drawn areas) appear mottled and uneven. This is O
When projected onto a screen using HP, the unevenness of the mottled pattern was magnified and became particularly noticeable.

Therefore, a first object of the present invention is to provide an inkjet recording sheet with improved image unevenness. In particular, it is an object of the present invention to provide an inkjet recording sheet in which unevenness in a mottled pattern (image unevenness in a uniformly drawn area) when a portion having a certain area is drawn in the same color is improved.

The second object is to provide an inkjet recording sheet that has the above characteristics and can be used as a color transparent array.

(Means for Solving the Problems) The above aspects of the present invention are characterized in that an inkjet recording sheet is provided with an ink absorbing layer on a transparent support, and has hydrophobic fine particles on the ink receiving surface. This was achieved with an inkjet recording sheet.

The present invention will be explained in detail below.

In the ink jet recording sheet of the present invention, an ink absorbing layer is provided on a transparent support, and hydrophobic fine particles are contained on the ink receiving surface of the recording sheet. In this way, it is thought that the presence of hydrophobic fine particles, especially on the surface, increases the contact angle on the surface of the recording sheet, making it difficult for ink fine particle droplets to coalesce, and improving image unevenness. .

Hydrophobic fine particles used in the present invention include hydrophobic oil droplets and hydrophobic solid fine particles, and the particle size of these fine particles is preferably about 0.01 to 10 μm, particularly 0.01 to 10 μm.
．． 02 to 2 μm is preferable.

The oily substance used in the hydrophobic oil droplets is preferably a high-boiling organic liquid with a boiling point of 140° C. or higher.

For example, U.S. Patent No. 2.322,027, U.S. Pat.
No. 3.514, No. 2.882,157, Special Publication No. 1972-
No. 23233, British Patent No. 958.441, 1, 2
No. 22,753, JP 4-50-82078, U.S. Pat. No. 2,353,262, U.S. Pat. No. 3,676.142,
No. 3,600.454, Japanese Patent Publication No. 51-27921,
No. 51-141623, No. 59-178455, No. 59-178451, No. 59-178452, No. 5
No. 9-178457, No. 59-178453, No. 59
Esters (e.g. phthalate esters, phosphate esters, fatty acid esters, etc.), amides (e.g. fatty acid amides, sulfamides, etc.), ethers, alcohols, paraffins, etc., described in No.-178454 etc. Examples include substances used as high boiling point organic solvents in the photographic field.

Further, in the present invention, for example, U.S. Patent No. 3,042.52
No. 2, British Patent No. 955,061, U.S. Patent No. 3,0
No. 80,317, No. 4,004゜927, No. 4,04
No. 7,958, No. 3,489.567, British Patent No. 1
It is particularly preferable to use the silicone-based oily substances described in , No. 143,118 and JP-A-60-140341.

A particularly preferred oily substance in the present invention is silicone oil. Examples of silicone oil include all silicone oils from dimethyl silicone oil to modified silicone oil in which various organic groups are introduced into dimethylsiloxane.

Next, typical examples of silicone oil used in the present invention will be listed, but the invention is not limited thereto.

General formula [N General formula [1] includes a linear siloxane having a siloxane unit represented by the following general formula [11-13] and a terminal group represented by the following general formula [I[-2].

General formula [1-11 %formula% General formula [ll-2] CH.

R+ 5iO- CH.

In the formula, R3 represents an alkyl, substituted alkyl, cycloalkyl, aryl, substituted aryl, hydrogen, alkoxy, substituted alkoxy, alkoxycarbonyl, or substituted alkoxycarbonyl group having 1 to 2 carbon atoms. m is 0 or a number greater than 1, n is a number greater than 1, m+n is 1 to 1
Represents the number 000. Preferably m+n is 2-500.

Specific examples of R in the compound represented by formula [I] include -CH, -CsHx, -CIIHI? , −C+J
gt, -CI4)129, -(CHz)so(
CzH40), (CJl, 0)bRz (where R2 is an alkyl group, a and b represent an integer of 0 or 1 or more),
-(C1h) 30H, -(C)It) 3NHK, -
(CHHz) JHCHzCHJHz, -(C)lx)
6COOH, -(CHz) +. C0OH,-(CHz
)+C0NHRt (Rz has the same meaning as above), -CLCH
2CFI, -CHzCJCJ'++, -0CHzCHz
O(CzH*0)a(CJbO)bRz(a,
b, Rt have the same meanings as above], and the like.

Next, representative examples of compounds represented by the general formula [I] will be shown.

CH3 (CH+) 5si-0-JSi-0)nrSi (C
Hz) 3H3 1-2 CH3 (CHs)asi-OASi-0)-nrSi(CH3
)zCI.

1-3 CH2 (CH3) zsi-0-JSi-0)yr-3i (
C) 13) 3J11 ■ 0(CzH40)yr(CJbOh-Cdbl CH3(C1h) 3H ShiH, (L;H,)3NH.

■ NHCHzCHgNHz 1-20 co.

(CH3)*5i-0-JSi-0)rnrSi(CH
I) 3C1,t Sushi-H,,L;H3 I 23 CHzCHzCJ+3I (CH3) zsi-0-(Si-0)rr-5i (
CH3) 3Ctl+ 1 24 HzCHzCh(CH3)
:+5i-0-(Si-OhT "Si (C)13)"
3CH3 Shi13 LJh Lil'131
2B Cl1lH3? (CH3) :+
5i-(1-(Si-0'Frr-Si(CHz) s
Summer CH.

l01hl Among the above, those having a carboxyl group in their structure are particularly preferred. And the carboxy equivalent is 120-6
000, particularly preferably 120 to 4000. Here, the carboxy equivalent is the value obtained by dividing the molecular weight by the number of carboxyl groups contained therein.

Methods for producing compounds of the general formula [H are known, for example, F.
G. N. G. Stone (F, G, A, 5tone) and D. G. Graham (W, A, G).

Graham), “Inorganic Volimers” (
Academic Press 1962 edition), pp. 230-231 and 288-295, by W. Knoll (W, N.
o1l), “Chemistry and Technology
Of Silicones (Academic Press 1968)
pp. 209-211 of P.F. Pruins (2015 edition)
P, F, Bruins)! J.P. Kennedy et al.
dy et, al.) li, "Bipolymer", Vol. 23, Part 2, pp. 773-775, etc., as well as various components as specifically shown in, for example, Japanese Patent Publication No. 36-22361. A method by hydrolysis of organochlorosilane, for example, Japanese Patent Publication No. 35-10771, Japanese Patent Publication No. 4
Addition reactions of siloxanes containing SiH groups to olefins using metal catalysts as shown in US Pat.
No. 917.480, Ind. & Eng. Chew.

Prod, Res, & Dev, + Volume 6, Na2,
88 pages (1967), "Chemistry and Industry" magazine published by the Chemical Society of Japan, Vol. 19, p. 147 (1966), "Industrial Chemistry Magazine", Vol. 73, p. 78 (1970), British Patent No. 9
16,561, French Patent No. 1.353.669, etc., etc., for the synthesis of polyorganosiloxane containing polyethylene oxide.

The viscosity of the oily substance used in the present invention is not particularly limited;
Any compound that can be synthesized by a conventional method can provide the desired effect, but those exhibiting a viscosity of about 20 to 100,000 centistokes when measured at 25° C. are suitable.

Many of the silicone oils used in the present invention are commercially available, such as Shin-Etsu Chemical's brand name KF410 and KF410.
412, KF413, KF351, KF945, KF6
15, K851, X-22-819, FLloo, KF
862, K F 86.5, X-22-980, KFl
ooT, X-60-164, X-22-3710, X-
22-3715, KF-910, X-22-160B, etc.

Moreover, an oily fluorine compound can be used as the hydrophobic oil droplets of the present invention.

A specific example of the oily fluorine compound is fluorine oil. Fluorine oil is commercially available and can be easily obtained. For example, it is commercially available from Daikin Industries under the trade names Guyfroil [F] and Demnum 0, and from DuPont under the trade names Krytox 1514 and Krytox 1525.
, 240AC1 LPV, 1506, 1618,
It is commercially available under 1645.

In the present invention, a typical method for incorporating an oily substance such as silicone oil into the ink absorbing layer is to add an oily substance such as silicone oil as necessary to a low-containing agent such as methyl acetate, ethyl acetate, butyl propionate, cyclohexanol, etc. Dissolved in a boiling point solvent, and optionally a surfactant such as anionic surfactants such as alkylbenzenesulfonic acids and alkylnaphthalenesulfonic acids and/or nonionic surfactants such as sorbitan sesquioleate and sorbitan monolaurate. Mix it with a hydrophilic colloid solution such as gelatin using a high-speed rotating mixer, colloid mill, or ultrasonic dispersion device, and apply the resulting dispersion or add it to a separately prepared coating solution. do it.

Next, the hydrophobic solid fine particles used in the present invention will be described.

Examples of the hydrophobic solid fine particles include fine particles of solid fluorine compound resin and the like. Specific examples of these solid fluorine compound resins include tetrafluoroethylene resin, vinylidene fluoride resin, trifluorochloroethylene resin, hexafluoropropylene resin, and fluoroethylene-propylene copolymer resin.

These solid fluorine compound resins are commercially available and can be easily obtained. For example, tetrafluoroethylene resins are available from Daikin Industries under the trade name Lublon [Phase] and Polyflon [Phase]; from Mitsui-DuPont Fluorochemicals Co., Ltd. under the trade name Teflon (3°J); as vinylidene fluoride resins, Daikin Product name: NEOFLON 0■D from Kogyo
3. Fluorinated chlorinated ethylene resin is available from Daikin Industries under the trade name NEOFLON@CTFE; and hexafluoropropylene resin is available from Daikin Industries under the trade name NEOFLON@FEP: Fluorinated ethylene-propylene copolymer The resin is commercially available from Mitsui DuPont Fluorochemical Company under the trade name Teflon@120J.

The solid hydrophobic fluorine compound resin is preferably dispersed in water as fine particles in the form of latex, and is added to the coating liquid for the ink absorbing layer and applied.

The coating amount of the hydrophobic fine particles of the present invention is 0.001 to 5 g/
rrr is preferable, more preferably 0.005 to 2 g/
It is particularly preferably 0.01 to Ig/bo.

In the present invention, a binder is used in the aqueous ink absorption layer.

The binders used in the present invention include: (1) a compound having high solubility or swelling property in water (compound A), and (2) a compound (compound A) having high solubility or swelling property in high-boiling polar organic solvents such as polyalcohol. A mixture with B) is preferred.

Compound A includes gelatin, polyvinyl alcohol, and superabsorbent polymers. Examples of gelatin include acid-treated gelatin, alkali-treated gelatin, and gelatin derivatives. The superabsorbent polymer contains 10% or more of COO- groups and/or 5O1- groups, preferably 3
It is a polymer containing 0% or more, and examples thereof include sodium polyacrylate and vinyl acrylate alcohol copolymer.

Compound B includes water-soluble cellulose derivatives such as carboxymethylcellulose, methylcellulose, hydroxyethylcellulose, polyvinylpyrrolidone, polyethylene glycol, and polypropylene glycol.

In the present invention, the ratio (weight ratio) of compound A to compound B used in combination varies depending on the types of compounds to be combined, but preferably the ratio (weight ratio) of compound A to compound B is 20/80 to 80. /20.

In the present invention, the following water-soluble binder can be used in combination with the above Compound A and Compound B in the water-based ink absorbing layer.

Specific examples of water-soluble binders used in combination include vinyl polymers such as polyvinylpyridinium halide, cationic modified polyvinyl alcohol, and derivatives thereof (JP-A-60-145879, JP-A-60-220750).
No. 61-143177, No. 61-235182, No. 61-235183, No. 61-237681,
61-261089), polymers containing acrylic groups such as polyacrylamide, polydimethylacrylamide, polydimethylaminoacrylate, acrylic acid methacrylic acid copolymer salt, and polysodium methacrylate (see JP-A-60-168651, 62
-9988), starch, oxidized starch, carboxyl starch, dialdehyde starch, cationic starch, dextrin, sodium alginate, gum arabic, casein, pullulan, dextran, ethyl cellulose, hydroxypropyl cellulose, and other natural polymers or their derivatives (see No. 59-174382, No. 6
No. 0-262685, No. 61-143177, No. 61
-181679, 61-193879, 61-
287782), polyvinyl ether, alkyl vinyl maleate copolymer, N-vinylpyrrole maleate copolymer,
Synthetic polymers such as polyethyleneimine (JP-A-61-
No. 32787, No. 61-237680, No. 61-27
7483) and water-soluble polymers described in JP-A-56-58869.

A surfactant can be used in the aqueous ink absorption layer. As the surfactant, various types of anionic, cationic, betaine, and nonionic surfactants can be used, and preferred surfactants include fluorine-based surfactants.

For example, saponins (steroids), alkylene oxide derivatives (e.g. polyethylene glycol, polyethylene glycol/polypropylene glycol condensates, polyethylene glycol alkyl ethers or polyethylene glycol alkyl aryl ethers, polyethylene glycol esters, polyethylene glycol sorbitan esters, polyalkylene glycols alkylamines or amides, polyethylene oxide adducts of silicone), glycidol derivatives (e.g. alkenylsuccinic acid polyglycerides, alkylphenol polyglycerides), fatty acid esters of polyhydric alcohols,
Nonionic surfactants such as alkyl esters such as;
Alkyl carboxylate, alkyl sulfonate, alkylbenzene sulfonate, alkylnaphthalene sulfonate, alkyl sulfate, alkyl phosphate, N-acyl-N-alkyl tauric acid, sulfosuccinate, sulfoalkyl poly Anionic surfactants containing acidic groups such as carboxy groups, sulfo groups, phospho groups, sulfate ester groups, phosphate ester groups such as oxyethylene alkylphenyl ethers and polyoxyethylene alkyleic acid esters; amino acids , amphoteric surfactants such as aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphoric esters, alkyl betaines, and amine oxides; alkyl amine salts,
Cationic surfactants such as aliphatic or aromatic quaternary ammonium salts, heterocyclic quaternary ammonium salts such as pyridinium and imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocycles can be used.

The fluorine-based surfactant may be any type of anionic, cationic, nonionic, or betaine type.
Moreover, it may be of low molecular weight or of high molecular weight.

Examples of such compounds include those of low molecular weight, such as U.S. Patent No. 3,775,126, U.S. Pat.
, No. 407,937, West German Patent No. 1,293,189, British Patent No. 1,259.398, Japanese Unexamined Patent Publication No. 1987-87
No. 826, No. 49-10722, No. 49-46733
No. 50-16525, No. 50-113221,
No. 50-161236, No. 50-99525, No. 5
No. 1-7917, No. 51-32322, No. 51-15
No. 1125, No. 51-151126, No. 51-151
No. 127, No. 51-129229, No. 52-1279
No. 74, No. 53-84712, No. 53-146622
Examples include fluorine-based surfactants described in Japanese Patent Application No. 54-14224, Japanese Patent No. 54-48520, and Japanese Patent No. 55-7762.

Also, as a polymer, US Pat. No. 4,175.
No. 969, No. 4,087,394, No. 4.016,1
No. 25, No. 3,676.123, No. 3,679,41
No. 1, No. 4,304,852, JP-A-52-1295
No. 20, No. 54-158222, No. 55-57842
No. 57-11342, No. 57-19735, No. 57-179837, "Chemistry Review Nα27, New Fluorine Chemistry" (Nippon Kagaku Venue, 1980), "Functional Fluorinated Polymers" (Nikkan Kogyo) (edited by Shimbunsha, 1982)
Examples include fluorine-based surfactants described in .

These fluorosurfactants can be produced by the methods described in the above-mentioned related documents, and further, for boat fishing, can be synthesized by fluorination of the corresponding hydrocarbon group. Regarding the fluorination of hydrocarbon groups, see "New Experimental Chemistry Course J, Vol. 1 4 [I] (No. 9, 1977)
(2013), pages 308-331.

Furthermore, fluorine-based surfactants described in JP-A-62-135826 can also be used.

In the present invention, the dry film thickness of the aqueous ink absorbing layer is 1 um.
It is preferably ~20μm, more preferably 2μm.
m to 10 μm.

In the present invention, the aqueous ink absorption layer may have a single layer structure or a multilayer structure.

Examples of multilayer structures include those described in JP-A-57-89954, JP-A-60-224578, and JP-A-61-12388. For example, JP-A-61-1238
The ink permeable layer described in No. 8 may be further provided on the aqueous ink absorbing layer of the present invention. ``However, in the case of a multilayer structure, the hydrophobic fine particles of the present invention are preferably present at least in the uppermost layer.

Furthermore, although the aqueous ink absorption layer is provided on at least one side of the transparent support, it is more preferable to provide it on both sides of the transparent support because this prevents the resulting recording sheet from curling.

As the transparent support used in the present invention, any conventionally known support can be used, such as polyester resin, diacetate resin, triacetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride resin,
Examples include films or plates of polyimide resin, cellophane, celluloid, and glass plates.

Such a transparent support has a thickness of about 10-200μ
It is preferable that the diameter is about m.

A method for forming an aqueous ink absorbing layer on the above-mentioned transparent support is to prepare a coating solution by dissolving or dispersing a mixture of a water-soluble binder and the hydrophobic fine particles of the present invention in water or an appropriate organic solvent; This coating solution may be applied onto a transparent support by a known method such as a roll coating method, a rod bar coating method, an air knife coating method, or a spray coating method, and then dried. Also,
The above mixture may be used by forming a single aqueous ink absorbing layer sheet by a known method such as a heat stretching method or a T-die method so that the aqueous ink absorbing layer also has a function as a support; The aqueous ink absorbing layer may be formed on the transparent support by laminating the sheet on the transparent support, hot-melt coating the mixture, or the like.

In the present invention, in order to improve the adhesion between the transparent support and the aqueous ink absorbing layer, the surface of the transparent support may be subjected to an anchor coating treatment or a corona discharge treatment.

In the present invention, for example, silica, clay, talc, diatomaceous earth, calcium carbonate, calcium sulfate, barium sulfate, aluminum silicate, synthetic zeolite, zinc oxide, lithopone, Fillers such as Satin White can also be dispersed in the aqueous ink absorbing layer.

Furthermore, the aqueous ink absorbing layer contains a dispersant, fluorescent dye, pH
Various known additives such as regulators, antifoaming agents, lubricants, antifading agents, preservatives, and gelatin hardening agents may also be added.

(Examples) Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited by these Examples.

A coating solution having the following composition was applied by bar coating onto a polyethylene terephthalate film support having a film thickness of 100 μm to obtain a recording sheet.

1st 1st direction Jyo: (Multilayer type) 2nd layer (outermost layer) Gelatin 0.5 g/M carboxymethylcellulose 0.7 Hydrophobic and hydrophobic particles *
X〃Surfactant (1)*
y //Surfactant (2)*
0.10 no! Surfactant (3)*
0.10 Matting agent (1)*
0.02 1st layer gelatin 2 g/pocarboxymethyl cellulose 3 1111-2 (multilayer type) 2nd layer (outermost layer) Gelatin 0.3 g/pocarboxymethyl cellulose 0.3 Sumikagel L5H*
0.3 〃Hydrophobic fine particles*
x Surfactant (1) * y
#Matting agent (1)* 0.
02〃First layer gelatin 1.7g/pocarboxymethyl cellulose 1.7〃Sumikagel L51 (*
1.7 〃Tight 1 to 5-= (single layer type) Acid-treated gelatin 2.5g/nf carboxymethylcellulose 3.5〃Hydrophobic and hydrophobic particles*
X〃Surfactant (1)*
y tt surfactant (2) *0.10
〃 Surfactant (3) *0.10〃 Matting agent (1) * 0.02 〃
Masumoto formula: (Single layer type) Alkali-treated gelatin 3.0 g/% Sodium polyacrylate 3.0 Hydrophobic and hydrophobic particles*
x〃Surfactant (1)*
ytt matting agent (1)*
0.015 〃Hydrophobic fine particles*: When the hydrophobic fine particles are oil droplets, they are added to a gelatin aqueous solution (10%) using a surfactant (1) as a dispersant at 10,000 rpm with a homogenizer.
Fine particles of oil droplets were prepared by emulsification and dispersion.

Surfactant (1) Sodium dodecylbenzenesulfonate Surfactant (2)*: Surfactant (3)*: Sumikagel L5H* Niacrylic acid-vinyl alcohol copolymer (manufactured by Sumitomo Chemical) Matting agent (1) )l benzoguanamine resin (manufactured by Nippon Shokubai Kagaku ■), an average particle size of 10 μm or more, and an image was recorded using an inkjet printer (manufactured by Sharp Corporation, LO-725), and an image was recorded as follows. The uniform drawing area unevenness was measured according to the method described in . The results are shown in Table-1.

Uniform drawing area unevenness: The uniform drawing area was projected and observed using an OHP, and the presence or absence of unevenness was visually determined.

(Single color areas: yellow, magenta, yellow, black; heavy color areas: red, green, blue) The evaluation criteria are as follows.

A: No unevenness B: Some unevenness C: Some unevenness D: Unevenness Table-1 * Compound 1: Compound Example 1-15 Compound 2: Compound Example 1-13 Compound 3: Fluorine oil (Demnum 0: manufactured by Daikin Industries) Compound 4: Teflon-30J (manufactured by DuPont/Mitsui Fluorochemicals) Compound 5: Teflon-120J (manufactured by DuPont/Mitsui Fluorochemicals) As is clear from the results in Table 1, the ink ciend recording sheet of the present invention In all cases, good results were obtained with little unevenness in the uniformly drawn area.

On the other hand, all of the comparative examples had unevenness in the uniformly drawn area and were inferior.

(Effects of the Invention) According to the present invention, an inkjet recording sheet with improved uniform drawing area unevenness, excellent light transmittance, and suitable for use as an OHP original was obtained.

Before procedural amendment April 15, 1986

Claims (1)

[Claims] An inkjet recording sheet comprising an ink absorbing layer provided on a transparent support, the inkjet recording sheet having hydrophobic fine particles on the ink receiving surface.