JPH07156537A - Recording paper - Google Patents

Abstract

PURPOSE:To provide recording paper divertible to ink jet printing paper and electrophotographic transfer paper. CONSTITUTION:Recording paper has a liquid absorbing characteristic wherein the liquid absorption coefficient Ka of aqueous ink measured by a J. TAPPI paper pulp test method No. 51 (liquid absoptivity test method of paper and cardboard-Bristol method) is 2900Xl/m<2>.s<1/2> or less and a value of the product of Stockigt 3 sizing degree X oil absorptivity of 3.0X10<3> or less and contains no calcium carbonate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording sheet which has excellent recording suitability as an ink jet recording sheet and also has excellent transportability and transferability required as an electrophotographic transfer sheet.

[0002]

2. Description of the Related Art Ink jet paper is required to have a high print density without the ink penetrating too deeply into the paper layer, the adhered ink does not bleed, and the adhered ink follows the fibers on the paper surface. That is, feathering that occurs when the ink is bleeding does not occur, ink that adheres to the surface of the paper dries quickly, and does not become dirty even when it touches the printing device.

In order to satisfy these characteristics, conventionally, a coated paper type in which a porous ink absorbing layer is provided on the surface has been used in order to improve the ink absorbing performance of an ink jet paper, using a normal high quality paper as a base paper. Came.

However, these coated papers lack the toner fixing property in an electrostatic transfer type (PPC) copying machine / printer and the transportability in the copying machine / copying machine.
It has been difficult to use as so-called electrophotographic transfer paper.

On the other hand, the characteristics required for the electrophotographic transfer paper are, as described above, good transferability of the toner, good transportability in the copying machine, and passing through the heat roll for fixing the toner. The heat curl received is small, or it does not contain a substance that causes abrasion of the photoconductor, avoids mixing of foreign matter such as paper powder into the toner, etc. However, when these electrophotographic transfer papers are used for the above ink jet recording, they cause problems such as bleeding, feathering, strike-through, poor fixability, and decrease in print density. The paper was not adaptable.

[0006] Recycled paper containing waste paper pulp has a drawback that bleeding and feathering cannot be overcome due to the influence of mechanical pulp.

[0007] As described above, when it is attempted to satisfy the ink jet printing suitability, the suitability as the electrophotographic transfer paper cannot be obtained, and conversely, when the suitability as the electrophotographic transfer paper is satisfied, the ink jet print suitability is impaired. Because of this, they could not be diverted from each other.

[0008]

DISCLOSURE OF THE INVENTION The present invention has no ink bleeding and feathering as an ink jet recording paper, has good colorability, has excellent ink jet printing suitability, and is easy to carry as an electrophotographic transfer paper. The present invention provides a recording sheet having excellent transferability, which is suitable as both an inkjet recording sheet and an electrophotographic transfer sheet.

[0009]

The present invention relates to a sheet for solving the above-mentioned problems, and as a result of various studies and trials, J. TAPPI paper pulp test method No. 51 (liquid absorption test method for paper and paperboard-Bristow's method), the liquid absorption coefficient Ka by the aqueous ink is 2900 μl / m ²
・^Has a liquid absorption property of s ^1/2 or less, and has a product value of stekihide size x oil absorption of 3.0
The result is that the paper which is not more than × 10 ³ and which does not contain calcium carbonate is a recording paper which has ink jet printing suitability and has characteristics required as an electrophotographic transfer paper. is there.

[0010]

EXAMPLES The paper used in the present invention is formed mainly of known wood pulp. They are chemical pulp and bleached hardwood kraft pulp, and 100% virgin pulp such as bleached softwood kraft pulp.

The present invention also makes it possible to use waste paper pulp including mechanical pulp as a raw material.

Conventionally, mechanical pulp (waste paper pulp) was not good in ink jet printability (particularly feathering), but in the present invention, good ink jet printability was obtained even in base paper containing waste paper pulp.

It is desirable that the blending ratio of used paper does not exceed 50% by weight, but this blending amount does not limit the present invention.

The above-mentioned base paper is made from pulp that has been beaten to 300 to 500 ml CSF (Canadian Standard Freeness) within the range for making general high-quality paper.

It is usual to add a filler to the above-mentioned base paper. The present invention focused on this filler.

In ink jet recording, the ink attached to the paper is held on the paper surface for an extremely short time, then penetrates into the paper layer and is fixed as the solvent evaporates. It was found that the dye in the ink when held may not develop color as designed.

The inventors have found that the color development differs depending on the filler added to the paper. That is, among the commonly used fillers for papermaking, such as clay, calcium carbonate, talc, titanium dioxide, and synthetic silica, calcium carbonate particularly affects the color developability of black ink, and redness appears in certain black ink. It is to exhibit a tinged color.

It is presumed that this is because the calcium ion of calcium carbonate is dissolved in water which is the solvent of the ink and reacts with the dye component in the ink to develop a red color. Therefore, it is desirable that the filler added to this paper does not have calcium ions.

Further, the above base paper includes a sizing agent, a paper strengthening agent,
A yield improver, a fixing agent, a dye, and other papermaking aids are added.

A coating solution containing a water-soluble polymer is applied to the base paper of the present invention. Water-soluble polymers are starch, kaizen, methyl cellulose, carboxymethyl cellulose,
Examples are polyvinyl alcohol, polyacrylic amide, hydroxyethyl cellulose, polyvinylpyrrolidone and the like.

In addition to such water-soluble polymers, the coating liquid includes surface sizing agents such as styrene / acrylic copolymers and styrene / maleic anhydride copolymers, so-called conductive agents such as polymer electrolyte inorganic salts, lubricants and defoaming agents. Etc. are added if necessary.

[0022] The coating liquid size less, bill blade coater, a gate roll coater, a rod coater, is coated with an air knife coater, the coating weight is desirably less than many 5 g / m ² from 0.5 g / m ² .

Various characteristics of the recording paper thus obtained are measured.

J. TAPPI paper pulp test method No. 5
1 (Liquid absorption test method for paper and paperboard-Bristow method)
The relationship between the amount of liquid transferred to the paper and the absorption time was obtained using the dynamic permeability measuring device (manufactured by Toyo Seiki Co., Ltd.) specified in 1.

The slit width of the head is 1 mm, the load applied to the contact surface with the paper is 0.5 kg, the ink amount is 40 μl, and the composition of the aqueous ink used is as follows.

Naphthol green B 1 part Diethylene glycol 5 parts Ethanol 20 parts Distilled water 74 parts The absorption coefficient Ka can be determined from the liquid transfer amount and the absorption time.

The present inventors have found that the paper manufactured as described above has an absorption coefficient Ka of 2900 μl / m ² ·
It has been found that when it is smaller than s ^1/2 , the ink jet printing suitability, especially the ink color developability and feathering are good.

Furthermore, the Steckigt size degree of the paper (JIS
P8122) and oil absorption (JIS P3001) were measured. The Steckigt sizing degree (size degree) represents the penetration time of water into the paper layer, and the oil absorption degree represents the penetration time of light oil into the paper layer.

When the product of the size degree (second) and the oil absorption degree (second) of the paper manufactured as described above, that is, the value of the size degree × the oil absorption degree is less than 3.0 × 10 ³ , the ink jet printing suitability, particularly It has been found that the feathering and ink fixability are good.

It is considered that the three factors described above do not individually have a causal relationship with the ink jet printing suitability, but complement each other to obtain a synergistic effect.

Example 1 LBKP 100%, 450 m
To 100 parts of the raw material beaten into lCSF, 0.05 parts of sizing agent alkenyl succinic anhydride (ASA), 0.5 parts of cationic starch and 7 parts of kaolin were added internally, and the basis weight was 64 g / m ^2.
I got the base paper. This base paper was coated with a coating solution containing 5% of oxidized starch, 0.05% of surface sizing agent and 0.1% of conductive agent by a size press to give an absorption coefficient Ka of 1600 μl / m ² · s ^1/2 and A recording sheet was obtained such that the size degree × the oil supply degree was 2800.

(Example 2) 0.02 parts of a sizing agent alkyl ketene dimer (AKD), 0.5 part of cationic starch, and 7 parts of kaolin were added to the raw material of Example 1 to obtain a basis weight of 64 g.
/ M ² base paper, 5% oxidized starch, surface sizing agent 0.02
%, Conductive agent 0.1%, lubricant 0.02% by a size press, the absorption coefficient Ka is 1500 μl / m ² ·
A recording paper having s ^1/2 and a size degree × oil supply degree of 2400 was obtained.

Example 3 Kaolin and talc were mixed as a filler of Example 1 in a ratio of 70:30 and 7 parts were added,
The same size press treatment as in Example 1 was performed to obtain an absorption coefficient Ka.
Of 2900 μl / m ² · s ^1/2 and the degree of size × the degree of oil supply was 1800.

(Example 4) Using 50% LBKP and 50% waste paper pulp as raw materials, the same chemicals and added amounts as in Example 1 were used, the absorption coefficient Ka was 2500 μl / m ² · s ^1/2 , and the degree of size × the degree of oil supply was A recording paper having a size of 2500 was obtained.

(Comparative Example 1) LBKP 100%, 450 m
lCSF 0.5 parts rosin sizing agent on 100 parts of beaten raw material
Parts, 2.5 parts of sulfuric acid band, and 7 parts of kaolin were added internally to obtain a base paper having a basis weight of 64 g / m ² . 6% oxidized starch on this base paper,
A coating solution of surface sizing agent 0.06% and conductive agent 0.1% was applied by a size press, and the absorption coefficient Ka was 10400 μl /
A recording paper having m ² · s ^1/2 and a size degree × lubrication degree of 3500 was obtained.

(Comparative Example 2) AKD0.
Oxidized starch 6 was added to the base paper of 64 g / m ² obtained by internally adding 03 parts, 0.5 parts of cationic starch and 7 parts of precipitated calcium carbonate.
%, Surface sizing agent 0.06%, and conductive agent 0.1% are applied by a size press, and the absorption coefficient Ka is 6100 μl.
/ M ² · s ^1/2 and a recording paper having a size degree x a lubrication degree of 3900 was obtained.

(Comparative Example 3) A was added to 100 parts of the raw material of Comparative Example 1.
Filler 7 in which SA 0.05 parts, cationic starch 0.5 parts, light calcium carbonate and carion are mixed in a ratio of 70:30
6 g of oxidized starch was added to the obtained 64 g / m ² base paper,
A coating solution of 0.06% surface sizing agent and 0.1% conductive agent was applied by a size press, and the absorption coefficient Ka was 7800 μl / m.
A recording paper having a size of ² · s ^1/2 and a size degree × lubrication degree of 3300 was obtained.

COMPARATIVE EXAMPLE 4 The filler of Comparative Example 3 was made of 100% heavy calcium carbonate, and the absorption coefficient Ka was 4700 μ.
A recording paper having a size of 1 / m ² · s ^1/2 and a degree of size × degree of lubrication of 3000 was obtained.

(Comparative example 5) 0.06 parts of ASA, 0.6 parts of cationic starch and 7 parts of light calcium carbonate were internally added to 100 parts of a raw material containing 50% LBKP and 50% waste paper pulp to obtain 64 g / m ² . Oxidized starch 5%, surface sizing agent 0.
A recording liquid having an absorption coefficient Ka of 5000 μl / m ² · s ^1/2 and a size degree × lubrication degree of 3000 is obtained by applying a coating liquid of 06% and a conductive agent of 0.1% by a size press. Obtained.

(Characteristics and Evaluation of Recording Paper) Characteristics and inkjet evaluation of recording papers of Examples 1 to 4 and Comparative Examples 1 to 5, P
Table 1 shows the results of the PC copier copy evaluation.

[0041]

[Table 1] For inkjet printing, an inkjet printer (BJ-10V) manufactured by Canon Inc. was used. The black color development of the inkjet printing evaluation item was measured with a spectroscopic color difference meter (SZ-Σ80 manufactured by Nippon Denshoku Industries Co., Ltd.) after printing with black ink and the hue (L *, a * b *) of the solid black portion. , ⊚ to × are evaluated.

Feathering was visually evaluated on the printed portion of the alphabet, and was evaluated on a scale of 5 from ⊚ to ×.

The fixing property is determined by wiping the solid printed portion with a non-woven fabric and measuring the time until rubbing does not occur.
It was evaluated in three stages.

PPC copier manufactured by Fuji Xerox Co., Ltd.
XEROX-9300 was used.

The transportability was evaluated by cutting the recording paper to A4 size, performing 3000 double-sided copies, and evaluating paper jam, double feeding, folding, wrinkling, and sorter property in three grades from ⊚ to Δ.

[0046]

The composition of the base paper is bleached virgin pulp 100.
%, Or a paper containing 50% or less of waste paper pulp, the liquid absorption coefficient Ka of the Bristow method with water-based ink
Has a liquid absorption property of 2900 μl / m ² · s ^1/2 or less, and a product value of Steckigt sizing degree × oil absorption is 3.
Paper was produced which was characterized in that it was 0 × 10 ³ or less and did not contain calcium carbonate.

When printing was carried out on this paper with an ink jet printer, it was a paper having excellent coloring properties of black ink, no ink bleeding, no feathering, and good ink jet printing suitability.

When this paper was subjected to a print test using an electrostatic copying machine (PPC), excellent transportability and transferability were obtained.

According to the present invention, one kind of recording paper can be used as an ink jet printing paper and an electrophotographic transfer paper and can be used for the convenience of users, which is extremely economical.

Further, it is possible to use the paper containing the waste paper pulp which is not suitable as the ink jet printing paper, and it is possible to reduce the cost.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 7, 1994

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

However, these coated paper types lack the toner fixing property in an electrostatic transfer type (PPC) copying machine / printer and the transportability in the copying machine / printer , and are used as so-called electrophotographic transfer papers. It was hard to do.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

On the other hand, the characteristics required for the electrophotographic transfer paper are, as described above, good transferability of toner, good transportability in the copying machine, and heat roll for fixing toner. The current electrophotographic transfer paper is the one that passes through the paper but has a small thermal curl received there, or does not contain a substance that causes abrasion of the photoconductor, and that foreign matter such as paper powder is not mixed into the toner. Various proposals have been made to improve these suitability, but on the other hand, when these electrophotographic transfer papers are used for the above-mentioned ink jet recording, they cause problems such as bleeding, feathering, strikethrough, poor fixability, and decrease in print density. However, the inkjet recording paper lacks adaptability.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

[0009]

The present invention relates to a sheet for solving the above-mentioned problems, and as a result of various studies and trials, J. TAPPI paper pulp test method No. 51 (liquid absorption test method for paper and paperboard-Bristow's method), the liquid absorption coefficient Ka by water-based ink is 2900 μl / m ²
・^Has a liquid absorption characteristic of s ^1/2 or less, and has a product value of Steckigt sizing degree × oil absorption degree of 3.0
The result is that the paper which is not more than × 10 ³ and does not contain calcium carbonate is a recording paper which has ink jet printability and has the properties required as an electrophotographic transfer paper. is there.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

A coating solution containing a water-soluble polymer is applied to the base paper of the present invention. Water-soluble polymer is starch, casei
Emissions, methylcellulose, carboxymethylcellulose,
Examples are polyvinyl alcohol, polyacrylic amide, hydroxyethyl cellulose, polyvinylpyrrolidone and the like.

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

[0022] The coating liquid size press, bill blade coater, a gate roll coater, a rod coater, is coated with an air knife coater, the coating weight is desirably less than many 5 g / ^{m 2} from 0.5 g / ^{m 2} .

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

The slit width of the head is 1 mm, the load on the contact surface with the paper is 0.1 MPa , the ink amount is 40 μl,
The composition of the aqueous ink used is as follows.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0035

[Correction method] Change

[Correction content]

(Comparative Example 1) LBKP 100%, 450 m
100 parts of the raw material beaten to lCSF was added with rosin sizing agent.
5 parts, 2.5 parts of sulfuric acid band, and 7 parts of kaolin were added internally to obtain a base paper having a basis weight of 64 g / m ² . Oxidized starch 6 on this base paper
%, Surface sizing agent 0.06%, conductive agent 0.1% by coating with a size press, absorption coefficient Ka is 10400μ
1 / m ² · s ^1/2 and size degree x oil supply degree is 3500
I got a recording paper that would be.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction content]

(Comparative Example 2) AKD0.
03 parts, cationic starch 0.5 parts, light calcium carbonate 7
6 g of oxidized starch was added to the obtained base paper of 64 g / m ² ,
A coating solution of surface sizing agent 0.06% and conductive agent 0.1% is applied by a size press, and the absorption coefficient Ka is 6100 μl / m.
A recording paper having a size of ² · s ^1/2 and a size degree × lubrication degree of 3900 was obtained.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction content]

(Characteristics and Evaluation of Recording Paper) Characteristics of recording papers of Examples 1 to 4 and Comparative Examples 1 to 5 and evaluation of ink jet printing
And shows a PPC copier copy evaluation results are shown in Table 1 in Annex.

[Procedure Amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction content]

[0041]

[Table 1] For inkjet printing, an inkjet printer (BJ-10V) manufactured by Canon Inc. was used. The black color development of the inkjet printing evaluation item is measured with a spectroscopic color difference meter (SZ-Σ80 manufactured by Nippon Denshoku Industries Co., Ltd.) after printing with black ink and the hue (L *, a * , b *) of the solid black portion. ◎ ～ × 5
Evaluate in stages.

Claims (1)

[Claims] 1. A method according to J. TAPPI paper pulp test method No. 5
1 (Liquid absorption test method for paper and paperboard-Bristow method)
The liquid absorption coefficient Ka of the water-based ink is 2900 μl /
A recording paper having a liquid absorption characteristic of m ² · s ^1/2 or less, a product value of Steckigt sizing degree × oil absorption degree of 3.0 × 10 ³ or less, and containing no calcium carbonate.