JPS5920696A - Ink jet recording paper - Google Patents

Abstract

PURPOSE:To provide the titled paper which makes an image resistant to water at a high level, by coating or impregnating a support with dimethyldiallylammonium chloride polymer. CONSTITUTION:A support (e.g. recording paper coated with talc, non-gluey siloca powder, CaCO3, TiO2, PVA, hydroxyethylcellulose or the like) is coated or impregnated with a dimethyldiallylammonium chloride polymer composed of a monomer of the formula to form an ink jet recording paper. This also provides a significant effect for the water resistance of a colored image as well as black one.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inkjet recording paper in which images formed on the recording paper are highly waterproof.

The inkjet recording method is being applied to facsimiles, various printers, etc. because of its low noise, ease of colorization, and high-speed recording. -Generally, plain paper can be used in the inkjet recording method, but in order to obtain good recording, the white paper must meet the following conditions.

Firstly, the ink absorbency is good, and ink droplets adhering to the paper surface are quickly absorbed into the inside of the paper layer, resulting in an apparent rolling state.Secondly, the ink dots spread out on the paper surface. It is to suppress the

In general, paper with high ink absorption properties increases the speed at which ink dots spread.
The conditions can be said to be contradictory.

For this reason, efforts have been made to harmonize the above two conditions, and a wide variety of paper products have been developed, such as low-density paper without the addition of sizing agents and Cocute paper coated with various pigments using water-soluble polymer binders. A jet recording paper has been developed.

On the other hand, inkjet recording usually uses water-based ink, and this water-based ink is generally composed of water-soluble dyes classified as direct dyes, acid dyes, and basic dyes, water, dye solubilizers, wetting agents, etc. Ru.

As the field of use of the above-mentioned inkjet recording method expands, customers' quality requirements for ink jet recordings have also become stricter, and in particular, water resistance has become a requirement for recorded materials. For example, if printed matter recorded by Quinn Jet is posted outdoors,
Recorded materials may bleed due to rainwater, causing them to fade or disappear. Recorded materials may bleed and fade even if they are stored for a long period of time in a very high temperature environment, and this tendency is particularly common in color inkjet recorded materials.

As a method for making inkjet recorded matter water resistant, an inkjet recording method is proposed in JP-A-56-84992, in which water-based ink is printed on a recording medium containing a polycationic polymer electrolyte on its surface. and,
Polyethyleneimine is shown as a typical example of an easily available polycationic polymer electrolyte. However, as will be discussed later, adding polyethyleneimine does indeed improve the water resistance of black images.
The effect is small for color recorded images. For this reason, it is especially desired to improve the water resistance of color recorded images, and this is an important issue in promoting the spread of color ink jet recording systems.

The present invention is intended to solve the above-mentioned problems, and is based on the knowledge that dimethyldiallylammonium chloride polymer exhibits a special effect not only on point color recorded images but also on making color recorded images water resistant. The present invention provides an in-form jet recording paper characterized in that a support is pressure coated or impregnated with a dimethyldiallylammonium chloride polymer.

The dimethyldiallylammonium chloride polymer used in the present invention is a polymer having a monomer represented by the following structural formula as a constitutional unit.

This dimethyl diallylammonium chloride polymer is a hygroscopic white powder and is used as a conductive processing agent.Although it does not dissolve in organic solvents other than methanol, it dissolves well in water, and its aqueous solution can be acidic or alkaline. However, its characteristic feature is that it is extremely stable.

In the present invention, the dimethyldiallylammonium chloride polymer can be used as an aqueous solution by spraying on the surface of a known inkjet recording paper, by applying (impregnating) the surface of the paper using a size press, or by using a known coating type inkjet recording paper. Mix and blade into the paint on the recording paper.

The coating may be applied using a coating machine such as an air knife or a roll coater.

Therefore, the present invention is applicable to all types of inkjet recording paper, including recording paper filled with various fillers such as talc, kaolin, calcium carbonate, finely powdered urea-formalin resin filler, and non-adhesive silica powder. , acid clay, clay, talc.

Recording paper coated with white pigments such as calcium carbonate, diatomaceous earth, titanium oxide, barium sulfate, etc., with 8 types of cellulose 1II such as oxidized starch, gelatin, casein, polyvinyl alcohol, hydroxyethyl cellulose, and a water-soluble polymer binder such as polyvinylpyrrolidone. By using it for example, it is possible to obtain an inkjet recording paper having extremely high degree of water resistance (7J color image water resistance.
The amount of coating or impregnation of the dimethyldiallylammonium chloride polymer is α1 to Z 5 ? A sufficient water resistance effect of the image can be achieved at about /m2.

The present invention will be explained below with reference to examples.

[Example 1] According to the treatment of known coated type inkjet recording paper, 85 parts by weight (solid content) of a slurry of white carbon (Jilton R-2, manufactured by Mizusawa Chemical Co., Ltd.) as a pigment was added to completely quenched as a binder. 13 parts by weight (solid content) of a 14% aqueous solution of polyvinyl alcohol (manufactured by Kuraray, PVA1.17) and 2 parts by weight (solid content) of dimethyldiallylammonium chloride polymer (manufactured by Nittobo, Pass 1 (-10))
A paint with a solid content concentration of 15% was prepared by mixing the following. For comparison, in place of the above polymer, dimethyldiallylammonium chloride-sulfur dioxide copolymer (manufactured by Nittobo Co., Ltd., Danfix 202), which is a typical example of a polycation, and polyethyleneimine (manufactured by Perdisier Dye Chemicals, Polyξ N8
M) and polyamide epichlorohydrin (Dick)
・-Made by Cures.

Evinox EP-P30), and as pressure thione activators, coconut alkyldimethylbenzylammonium chloride (NOF Co., Ltd., F2-50E) and tetradecyldimethylpenzylammonium chloride (NOF Co., Ltd., M2-100), and non-ionic Each paint was prepared by mixing 2 parts by weight (solid content) of melamine formaldehyde resin (Sumitomo Chemical, Sumiraze 8IL613) as a water-resistant agent. No need to use any waterproofing agent - 85 parts by weight (solid content) of slurry of white carbon (Jilton l(-2)) mixed with 15 parts by weight (solid content) of a 14% aqueous solution of PVA1t7 Paints with a solid content concentration of 15% (Table 10A8) were also prepared.These paints were coated on commercially available high-quality paper with a 6o17m square meter and a Steckigt size of 20 seconds so that the coating amount was 8 to 121 f/m2. Inkjet recording papers A1 to A81!!

Quality tests for each of the above recording papers were conducted in the following manner.

First, using a Panafax 6000 manufactured by Matsushita Densen, black ink (rhTMAuKERK-111゜Dainippon Toyo Co., Ltd.) and red ink (JE1'MARKERIt-28) were injected.
0, manufactured by Dainippon Toyo Co., Ltd.) Each of black and red solid printing was performed using IC. The above red ink is made from a mixture of yellow and magenta components. The reflection density of the above recorded printed matter was measured using a yellow filter (Latten ÷ 4) for the red printed part.
7) and a magenta filter (RatuTenna 58), and for the dot printing area, there is a filter for printing (
The Macbeth concentration Hf was determined using Eri Rakuten + 106).

Next, the recorded printed material was immersed in distilled water at 25°C for 1 minute.
After drying in an air bath at 00°C, the reflection density of each color was measured in the same manner as above.

Furthermore, in order to evaluate the water resistance of the recorded printed matter, the color reduction rate of each of black and red was calculated according to the following formula.

Similarly, the color reduction rate of red was calculated using the total IT value of yellow and magenta. The results are shown in Table 1.

Table 1 shows that no matter which water-resistant agent is used, the color reduction rate is smaller than when no additive is used, and in particular, the reflection density of the black printed area hardly decreases even when immersed in water. is recognized.

However, regarding the red printed area, in the case of the water resistant agent of the reference example, a clear decrease in reflection density is seen in the yellow component or magenta component, whereas in the present invention, both are stable and the rate of color reduction is extremely small.

[Example 2] Recording paper was prepared in the following manner according to a known method for preparing plain (non-coated) type inkjet recording paper. That is, raw material pulp consisting of 20 parts by weight of NBKP with a freeness of 400 and 80 parts by weight of LBKP with a freeness of 300m/1, 1 clay (manufactured by Gohan Kogyo Co., Ltd., grade 1 clay)
30 parts by weight, and 5 parts by weight of poly7mide epichlorohydrin (Kymen 557, manufactured by Deitz Hercules) as a wet strength enhancer were added, and a sheet with a weight of 60 b was made using a Fourdrinier machine in a conventional manner. Furthermore, a plain type inkjet recording paper 11 was prepared by applying oxidized starch (manufactured by Tamago Cornstarch, Oji Ace B) at a solid content of 4 f/m' using a size press. Furthermore, on this recording paper, 3% aqueous solutions each of dimethyldiallylammonium chloride polymer (Nittobo [, Has 1 (-10)] and dimethyldiallylammonium chloride-sulfur dioxide copolymer (manufactured by Nittobo, Pass A-1208) were added. Recording papers 49 to 10 were prepared by coating each of these three with a size press to a t 5 tim" (in terms of solid content).
Table 2 shows the results of the water resistance test of the recorded matter of type 81 plain type recording paper.

From Table 2, when dimethino 1 and diallylammonium chloride polymers are used, even on plain type inkjet recording paper, not only the reflection density of the thermally printed area but also the reflection density of the yellow component and magenta component of the red printing area can be improved. It can be seen that the deterioration can be suppressed and it is effective in imparting water resistance to color inkjet recording paper.

Patent applicant: Jujo Paper Industries Co., Ltd. Written amendment to corporate procedures (voluntary) 10474/1974 Kazuo Wakasugi, Commissioner of the Japan Patent Office 1 Indication of the case 1980 Patent Application No. 7. j 0270 No. 2゛8″”
'4＞2cin,, Toki 4 At3, Relationship with the case of the person making the amendment Patent applicant 4, Agent 〒／／'l Including 9／／ -! ;/θ Otsu 6 Number of inventions increased by amendment (1) Amend "Borimin SMj to 1 Borimin P" on page 7/line 2 of the specification.

that's all

Claims (1)

[Claims] (1) An inkjet recording paper obtained by coating or impregnating a support with a dimethyldiallylammonium chloride polymer having a monomer represented by the following structural formula as a constituent unit.