JPH1165157A - Electrophotographic transfer paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer paper having good electrophotographic adaptability such as toner fixing property and paper feeding property and having excellent ink Jet adaptability without causing 'feathering' or 'strike through' by incorporating a neutral rosin sizing agent by wt.% and an acid-soluble aluminum salt by specified wt.%s into a transfer paper. SOLUTION: This electrophotographic transfer paper is produced in a paper making process using a paper making pulp slurry containing at least a filler, a neutral rosin sizing agent and aluminum sulfate with >=pH 7.0 of the paper making pH condition. The amts. of the neutral rosin sizing agent and the acid- soluble aluminum salt are controlled to 0.15 to 0.45 wt.% and 0.40 to 1.50 wt.% of the transfer paper, respectively. By controlling the amts. of the neutral rosin sizing agent and the acid-soluble aluminum salt to 0.15 to 0.45 wt.% and 0.40 to 1.50 wt.%, respectively, in the transfer paper, qualities in a level without any problems for practical use can be obtd. concerning to the ink jet adaptability such as 'feathering' and 'strike through'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic transfer paper having improved sizing properties, electrophotographic suitability, and ink jet suitability. More specifically, the present invention relates to an electrophotographic transfer paper excellent in toner fixing properties and paper feeding properties in an electrophotographic system and ink jet characteristics such as feathering and strike-through in an inkjet system.

[0002]

2. Description of the Related Art Conventionally, in the manufacture of paper, papermaking has been mainly performed in an acidic region using a sulfuric acid band and a rosin-based sizing agent. Calcium has been used as a filler, and papermaking has been gradually started from an acidic region to a neutral region. Further, as described in Paper Technical Association Vol. 44, No. 4, calcium carbonate has been used as a filler in electrophotographic transfer paper from the viewpoints of image quality maintenance and paper preservability, The pH of the papermaking system for producing electrophotographic transfer paper has also been in the neutral to alkaline range.

Examples of applying such a neutral papermaking technique to transfer paper for electrophotography are disclosed in JP-A-59-162560, JP-A-61-63854, and JP-A-61-67038.
In these publications, alkyl ketene dimer (hereinafter abbreviated as AKD) and alkenyl succinic anhydride (hereinafter abbreviated as ASA) are disclosed as sizing agents. I have. AKD
Makes use of the characteristics that can be easily handled, or obtains excellent sizing properties with a small amount of addition, and ASA has been used taking advantage of the characteristics of good rise in sizing properties.

However, these sizing agents are not without problems. AKD has a problem that the rise of size is slow and delicate control of size is difficult, and furthermore, a phenomenon in which a plurality of papers are fed at a time in a paper feeding unit of a copying machine, that is, a “double feed” occurs. Cheap. Further, ASA has a disadvantage that the stability of the sizing agent is poor, and dirt is easily generated from the press section to the dryer section during papermaking.

As countermeasures against the above-mentioned problems, reduction of the amount of AKD or ASA added, combined use with a cationic polymer type neutral sizing agent represented by styrene-dimethylaminoether (meth) acrylate-epihalohydrin modified product (Japanese Unexamined Patent Application Publication No. 55-132789 and 5
No. 7-112497) and an increase in the amount of surface-sized starch applied.

[0006] In recent years, these electrophotographic transfer papers have not always been used in the general market for only their intended uses, but have been increasingly used as printing paper for ink jet printers. However, if the size is not enough, ink bleeding occurs along the wood fiber such as "feathering",
In a solid printing portion such as "through print", the print quality is reduced such that ink is removed on the opposite side to the printing surface.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a transfer paper for electrophotography which is excellent in toner fixing property and paper feeding property in electrophotography and ink jet characteristics such as feathering and strike-through in ink jet method. That is.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned drawbacks, and as a result, have come to invent the electrophotographic transfer paper of the present invention.

That is, the electrophotographic transfer paper of the present invention is an electrophotographic transfer paper made by using a papermaking pulp slurry having a papermaking pH of at least 7.0 containing a filler, a neutral rosin sizing agent and a sulfate band. Wherein the content of the neutral rosin sizing agent in the transfer paper is 0.15 to 0.45% by weight,
When the content of the acid-soluble aluminum salt is 0.40 to 1.50
The transfer paper for neutral electrophotography is characterized in that the transfer paper is a weight percent.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The transfer paper for electrophotography of the present invention will be described in detail below.

As described above, the present inventors have studied especially neutral electrophotographic transfer paper from the viewpoints of the environment, the image quality maintenance and the storage stability of the electrophotographic transfer paper. The “neutral” electrophotographic transfer paper in the present invention refers to an electrophotographic transfer paper having a cold water extraction pH of 7.0 or more. Regarding the pH of paper extracted with cold water and the preservability of the paper, as described in the Japan Society of Paper and Technology, Vol. 38, No. 1, p. 48 to p. It is already known that the pH is improved when the pH is in the neutral to alkaline range. However, in the prior art,
It was very difficult to achieve both electrophotographic suitability and ink jet suitability.

Therefore, the present inventors firstly set the neutral to
A comparison was made between the sizing agent usable in the alkaline region and the paper feeding characteristics of the copying machine. As a result, the transfer paper for electrophotography of the present invention using a neutral rosin sizing agent as an internal sizing agent has a sizing property that does not cause any practical problems, but also has a "double feed" in a paper feeding portion of a copying machine. I found that no problems occurred.

The neutral rosin sizing agent in the present invention is:
For example, Paper-Paper Technical Association Vol. 47 No. 5, pp31-34 (1
993). Neutral rosin sizing agent is a raw material rosin, fortified rosin,
An emulsion type rosin sizing agent comprising an esterified rosin and an emulsifier.

Next, the present inventors conducted a comparative study on the relationship between the amount of neutral rosin sizing agent and the amount of acid-soluble aluminum salt contained in the electrophotographic transfer paper of the present invention and the suitability for inkjet. As a result, the content of the neutral rosin sizing agent contained in the transfer paper was 0.15 to 0.45% by weight, and the content of the acid-soluble aluminum salt was 0.40 to 0.40%.
It has been found that when the content is 1.50% by weight, it is possible to exhibit a practically acceptable level of quality such as "feathering" and "through-through" in ink jet suitability.

In the electrophotographic transfer paper of the present invention, if the content of the neutral rosin sizing agent is less than 0.15% by weight, the sizing property is not sufficient, and when printed with an ink jet printer, feathering occurs. And strikethrough occurs.

Even when the content of the neutral rosin sizing agent of the transfer paper is 0.15% by weight or more, it is necessary that the content of the acid-soluble aluminum salt is 0.40 to 1.50% by weight. is there. It is considered that the acid-soluble aluminum salt in the present invention is derived from a sulfate band added when the electrophotographic transfer paper of the present invention is made.

The sulfuric acid band has been cationic in the acidic region, and has been widely used as a retention agent in acidic papermaking. It is also considered that when used in combination with a rosin-based sizing agent used in acidic papermaking, rosin and aluminum ions derived from a sulfate band form a complex salt and exhibit good sizing properties.

In a neutral region where the electrophotographic transfer paper of the present invention is made, it is unlikely that the sulfate band has the same cationic property as the acidic region. However, the present inventors have conducted intensive studies on a method for expressing the size of a neutral rosin sizing agent, and have found that even a neutral rosin sizing agent requires aluminum ions derived from a sulfate band.

Although the detailed reason for the need for the sulfate band is unknown, the present inventors consider the following reasons. (1) The yield of the neutral rosin sizing agent itself is improved by using the sulfate band. (2) Although the sulfate band is deactivated in the neutral region, it does not deactivate immediately after the addition but reacts with the neutral rosin sizing agent during that period. (3) Free carboxylic acid is present in a part of the resin of the neutral rosin sizing agent, and the part expresses the sizing property by also becoming an aluminum salt.

The content of the neutral rosin sizing agent in the transfer paper is 0.15% by weight or more, and the content of the acid-soluble aluminum salt in the paper is 0.40 to 1.50% by weight. In the case of the above, it was found that the ink exhibited ink sizing properties for the ink jet printer.

When the content of the acid-soluble aluminum salt in the transfer paper is less than 0.4%, even if the content of the neutral rosin sizing agent is 0.15% or more, the sizing property for the ink of the ink jet printer can be improved. Is not sufficient, and feathering and strikethrough occur.

On the other hand, when the content of the acid-soluble aluminum salt in the transfer paper is 1.50% or more, the size of the ink for an ink jet printer is saturated.

As for the content of the neutral rosin sizing agent, in a state where a sufficient aluminum salt is present, as the content of the neutral rosin sizing agent increases, ink jet suitability such as feathering and strike-through increases. When the content of the neutral rosin sizing agent is 0.45% or more, the improvement effect is saturated. Further, in order to increase the content of the neutral rosin sizing agent, the amount of the sizing agent added to the papermaking slurry increases, which unnecessarily deteriorates the operability.

As described above, the neutral rosin sizing agent is used as the internal sizing agent, and the content of the neutral rosin sizing agent contained in the transfer paper is 0.15 to 0.45% by weight. And the content of the acid-soluble aluminum salt is 0.40
By setting the content to １．５1.50% by weight, it is possible to provide an electrophotographic transfer paper in which “double feed” does not occur in a paper feed portion of a copying machine and no strikethrough occurs even when printing with an inkjet printer. I knew I could do it.

The content of the neutral rosin sizing agent contained in the transfer paper for electrophotography of the present invention is determined by increasing or decreasing the amount of the neutral rosin sizing agent added to the pulp slurry when the transfer paper is made, and increasing the yield. It is possible to control a method such as improving the yield of a neutral rosin sizing agent by using an auxiliary agent alone or in combination.

The content of the acid-soluble aluminum salt contained in the transfer paper for electrophotography of the present invention is determined by increasing or decreasing the amount of the sulfuric acid band added to the pulp slurry when the transfer paper is made.
It is possible to control a method such as a method of adding a sulfuric acid band to the pulp slurry in a divided manner or a method of adjusting pH in a papermaking system alone or in combination.

The content of the neutral rosin sizing agent contained in the electrophotographic transfer paper of the present invention was determined according to the following procedure.

(1) 10 g of the electrophotographic transfer paper of the present invention was prepared in an absolutely dry state. The transfer paper was cut into a test piece of about 6 × 40 mm. (2) The transfer paper was immersed in concentrated hydrochloric acid or 1N hydrochloric acid for 5 minutes. Thereafter, the acid was washed and air dried. (3) The air-dried test pieces were extracted for 2.5 hours using a soxhlet extractor using acid ethanol containing 0.4% hydrochloric acid as an extract. (4) The extract obtained after the Soxhlet extraction was evaporated on a steam bath, and a certain amount of ether was added to dissolve the solid. (5) The ether solution in which the solid was dissolved was filtered through a 5C filter paper, and then the ether was distilled off, and the amount of the solid was weighed.
When weighing, a weigher capable of measuring to 0.1 mg precision was used. (6) The obtained solid content was regarded as a neutral rosin sizing agent component, and the ratio in the transfer paper was reported as a percentage with two decimal places.

The content of the acid-soluble aluminum salt contained in the electrophotographic transfer paper of the present invention was determined according to the following procedure.

(1) 3 g of the electrophotographic transfer paper of the present invention is prepared in a dry state. The transfer paper is cut into test pieces of about 10 × 10 mm. (2) Immerse the transfer paper in 50 ml of concentrated hydrochloric acid for 24 hours. (3) Add deionized water to the concentrated hydrochloric acid solution to make 1000 ml, stir well, and then stand still. (4) After standing, the supernatant was collected, and the amount of Al ions was quantified using an atomic absorption spectrometer. (5) From the amount of Al ions obtained according to the above procedure,
In consideration of the collection amount and the dilution ratio, Al ions were obtained from 3 g of the electrophotographic transfer paper of the present invention. This Al ion is considered to be derived from the sulfuric acid band added when the transfer paper was formed, and the sulfuric acid band (Al ₂ (SO ₄ ) ₃ .18H ₂
O) and converted to the “acid-soluble aluminum salt amount”. (6) The resulting "acid-soluble aluminum salt amount" was reported as a percentage of the transfer paper as a percentage with two decimal places.

Examples of the internal filler used in the electrophotographic transfer paper of the present invention include kaolin, clay, talc, diatomaceous earth, zeolite and the like in addition to light calcium carbonate and heavy calcium carbonate.

As a means for adjusting the papermaking pH of the transfer paper for electrophotography of the present invention to 7.0 or more, there is a method using calcium carbonate as a filler. At this time, the amount of calcium carbonate in the papermaking slurry was as follows:
0% or more is desirable.

When kaolin or the like is used as a filler, for example, as described in “Paper Size” (Kitao Book Trading Co., Ltd.), pages 156 to 159, an alkaline substance such as sodium aluminate is used for papermaking. It is also possible to adjust the pH by adding to the system.

It is considered that the ash content of the electrophotographic transfer paper of the present invention is 15% or less, preferably 5% to 10%. When the ash content is 15% or more, the sizing property is reduced, so that strikethrough and feathering are deteriorated.

On the surface of the electrophotographic transfer paper of the present invention, a binder such as starch or polyvinyl alcohol, a styrene / acrylic acid copolymer, a styrene / methacrylic acid copolymer, an acrylonitrile / vinyl formal / acrylic acid Surface sizing agents such as ester copolymers, styrene / maleic acid copolymers, dimensional stabilizers such as ethylene-urea resins, inorganic conductive agents such as sodium chloride and potassium chloride, organic conductive agents, surfactants, pigments, It is of course possible to apply a dye.

As a device for applying the above-mentioned binder and surface sizing agent, a conventional size press,
A gate roll size press, a film transfer type size press, a rod coater, a bill blade, a short dwell coater, or the like can be used. Among these coating apparatuses, it is desirable to use a method that impregnates the inside of the paper layer with the above-mentioned size press liquid.

As the support for the electrophotographic transfer paper of the present invention, a paper-like material such as a paper mainly composed of wood fibers or a non-woven fabric mainly composed of wood fibers or synthetic fibers is used. Wood pulp is NBKP, LBKP, N
In addition to BSP, LBSP, GP, TMP and the like, used paper pulp is used, and used alone or in combination as needed.

The raw materials for waste paper pulp referred to in the present invention include: top white, ruled white, cream white, card, and the like shown in the waste paper standard quality standard table of the Waste Paper Recycling Promotion Center.
Special white, medium white, imitation, fair white, Kent, white art, special top cut,
Another example is newspaper, magazine, etc. Further specific examples include uncoated computer paper, which is information-related paper,
Printer paper such as thermal paper, pressure-sensitive paper, and OA waste paper such as PPC paper, coated paper such as art paper, coated paper, lightly coated paper, matte paper, or fine paper, color fine, notebook,
Used paper such as stationery, wrapping paper, fancy paper, medium paper, newsprint, paper change, super-hanging paper, imitation paper, pure white roll paper, uncoated paper such as milk carton, and paperboard,
Chemical pulp paper, high-yield pulp-containing paper and the like are used, but are not particularly limited regardless of printing, copying, printing, and non-printing.

In the papermaking method of the present invention, a paper machine known in the papermaking industry, such as a fourdrinier paper machine, a twin wire paper machine, a combination paper machine, a round mesh paper machine, or a Yankee paper machine, can be used as appropriate.

The ink for ink jet recording according to the present invention is a recording liquid comprising the following colorant, liquid medium and other additives. Examples of the coloring agent include water-soluble dyes such as direct dyes, acid dyes, basic dyes, reactive dyes, and food dyes.

Examples of the solvent for the aqueous ink include water and various water-soluble organic solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, Alkyl alcohols having 1 to 4 carbon atoms such as isobutyl alcohol; amides such as dimethylformamide and dimethylacetamide; ketones or ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyethylene glycol and polypropylene glycol Polyalkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodig Call, hexylene glycol, an alkylene group such as diethylene glycol 2
And 6 alkylene glycols; lower alkyl ethers of polyhydric alcohols such as glycerin, ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol and monomethyl ether.

Among these many water-soluble organic solvents,
Polyhydric alcohols such as diethylene glycol, and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether are preferred.

Other additives include, for example, a pH adjuster, a metal sequestering agent, a fungicide, a viscosity adjuster, a surface tension adjuster, a wetting agent, a surfactant, and a rust inhibitor.

[0044]

The present invention will be described below with reference to examples of the present invention, but the present invention is not limited to these examples. Further, “parts” and “%” shown in Examples are
Unless indicated otherwise, parts by weight and% by weight are indicated.

Example 1 First, a pulp slurry was prepared according to the following base paper composition. In addition, pH of pulp slurry prepared with the following composition
Was 7.65. <Base paper composition> LBKP (freeness; 450 ml) 100 parts Calcium carbonate (Okutama Kogyo; Tamapearl TP121) 7 parts Sulfuric acid band 1.3 parts Cationized starch (National Starch; Cato3210) 1 part Neutral rosin size Agent (Arakawa Chemical Co., Ltd .; NT80) 0.30 part Yield improver (Himo Co., Ltd .; NR11LS) 0.02 part

A base paper made from a 0.3% by weight pulp slurry having the above composition at a papermaking width of 1300 mm and a papermaking speed of 150 m / min using a fourdrinier paper machine was subjected to size press using a liquid having the following composition. At this time, the solid content of the size press liquid was 1.5 g / m ² . <Composition of size press liquid> Oxidized starch (manufactured by Japan Food Processing Co., Ltd .; MS3800) 4 parts Surface sizing agent (manufactured by Harima Chemicals, KN-500) 0.3 parts Water 95.7 parts

As described above, an electrophotographic transfer paper having a basis weight of 64 g / m ² , a density of 0.75 g / cm ³ , and a water content of 5.0% was obtained.

Example 2 An electrophotographic transfer paper of Example 2 was prepared in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.40 part. The pH of the pulp slurry used to form the electrophotographic transfer paper of Example 2 was 7.65.
Met.

Example 3 An electrophotographic transfer paper of Example 3 was prepared in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.60 part. The pH of the pulp slurry used to form the electrophotographic transfer paper of Example 3 was 7.63.
Met.

Example 4 An electrophotographic transfer paper of Example 4 was produced in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.65 part. The pH of the pulp slurry used to form the electrophotographic transfer paper of Example 4 was 7.63.
Met.

Example 5 An electrophotographic transfer paper of Example 5 was prepared in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.75 part. The pH of the pulp slurry used to form the electrophotographic transfer paper of Example 5 was 7.61.
Met.

Example 6 The electrophotography of Example 6 was carried out in the same manner as in Example 1, except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.35 part and the amount of the sulfate band was changed to 0.8 part. Transfer paper was prepared. In addition, the pH of the pulp slurry when the electrophotographic transfer paper of Example 6 was made was 7.85.

Example 7 The electrophotography of Example 7 was carried out in the same manner as in Example 1, except that the amount of the neutral rosin sizing agent in the base paper composition was changed to 0.40 part and the amount of the sulfate band was changed to 0.8 part. Transfer paper was prepared. In addition, the pH of the pulp slurry when the electrophotographic transfer paper of Example 7 was made was 7.84.

Example 8 The electrophotography of Example 8 was carried out in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper composition was changed to 0.60 part and the amount of the sulfate band was changed to 0.8 part. Transfer paper was prepared. In addition, the pH of the pulp slurry when the electrophotographic transfer paper of Example 8 was made was 7.83.

Example 9 In Example 1, the amount of the sulfuric acid band in the base paper composition was 1.7.
The transfer paper for electrophotography of Example 9 was produced in the same manner except that the above-mentioned parts were used. The pH of the pulp slurry used to form the electrophotographic transfer paper of Example 9 was 7.45.

Example 10 The electrophotography of Example 10 was carried out in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper composition was changed to 0.40 part and the amount of the sulfate band was changed to 1.7 parts. Transfer paper was prepared. In addition, the pH of the pulp slurry at the time of forming the electrophotographic transfer paper of Example 10 was 7.44.

Example 11 The electrophotography of Example 11 was carried out in the same manner as in Example 1, except that the amount of the neutral rosin sizing agent in the base paper composition was changed to 0.60 part and the amount of the sulfate band was changed to 1.7 parts. Transfer paper was prepared. In addition, the pH of the pulp slurry at the time of forming the electrophotographic transfer paper of Example 11 was 7.43.

Example 12 An electrophotographic transfer paper of Example 12 was prepared in the same manner as in Example 1 except that the base paper was changed to the following base paper. In addition, pH of pulp slurry prepared with the following composition
7.00. <Base paper composition> LBKP (freeness: 450 ml) 100 parts Kaolin (PTRUTER ABDAI; BRU-30) 7 parts Sulfuric acid band 1.1 parts Cationized starch (National Starch; Cato 3210) 1 part Neutral rosin sizing agent (Arakawa Chemical; NT80) 0.30 part pH adjuster (sodium carbonate) 0.40 part Yield improver (Himo; NR11LS) 0.02 part

Comparative Example 1 An electrophotographic transfer paper of Comparative Example 1 was prepared in the same manner as in Example 1, except that the base paper composition was changed to the following base paper composition. In addition, pH of pulp slurry prepared with the following composition
Was 7.96. <Base paper composition> LBKP (freeness: 450 ml) 100 parts Calcium carbonate (Okutama Kogyo; Tamapearl TP121) 7 parts Sulfuric acid band 0.5 part Cationized starch (National Starch; Cato3210) 1 part Alkyl ketene dimer ( Arakawa Chemical Co .; Size Pine 903) 0.12 parts Yield improver (HIMO; NR11LS) 0.02 parts

Comparative Example 2 The electrophotograph of Comparative Example 2 was made in the same manner as in Example 1, except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.25 part and the amount of the sulfate band was changed to 0.8 part. Transfer paper was prepared. In addition, the pH of the pulp slurry when the electrophotographic transfer paper of Comparative Example 2 was made was 7.86.

Comparative Example 3 An electrophotographic transfer paper of Comparative Example 3 was prepared in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.20 part. The pH of the pulp slurry used in the paper making of the electrophotographic transfer paper of Comparative Example 3 was 7.66.
Met.

Comparative Example 4 The electrophotograph of Comparative Example 4 was made in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was changed to 0.60 part and the amount of the sulfate band was changed to 0.5 part. Transfer paper was prepared. In addition, the pH of the pulp slurry when the electrophotographic transfer paper of Comparative Example 4 was made was 7.96.

Comparative Example 5 The electrophotograph of Comparative Example 4 was made in the same manner as in Example 1 except that the amount of the neutral rosin sizing agent in the base paper was 0.90 part and the amount of the sulfate band was 0.5 part. Transfer paper was prepared. In addition, the pH of the pulp slurry when the electrophotographic transfer paper of Comparative Example 5 was made was 7.96.

The pH of the pulp slurry at the time of forming the electrophotographic transfer papers of Examples 1 to 12 and Comparative Examples 1 to 5 was adjusted to 25 ° C. and then adjusted to JIS Z88.
02-7. According to the pH meter manufactured by Yokogawa Electric Corporation (model: PH
8111-J).

The electrophotographic transfer papers of Examples 1 to 12 and Comparative Examples 1 to 5 were evaluated for electrophotographic suitability and ink jet suitability according to the following methods.

<Toner Fixing Property> The toner fixing property of the electrophotographic transfer paper described above was measured with a copying machine “SF” manufactured by Sharp Corporation.
9400 ”to print a solid printing portion on the transfer paper, and the printing portion has a cellophane tape No. After attaching 405, the cellophane tape is peeled off from the transfer paper. At this time, the degree of peeling of the toner from the printing portion was visually evaluated on a five-point scale. The evaluation criteria are as follows. 5: No toner is peeled off. 4: The toner is slightly peeled off, but is not conspicuous. 3: A portion where the toner is peeled off can be confirmed. 2: The toner is peeled, and the portion of the peeled toner is larger than the remaining portion. 1: all toner is peeled off.

<Feeding Characteristics> Regarding the feeding characteristics of the above-described electrophotographic transfer paper, the copying machine “SF940” manufactured by Sharp Corporation was used.
Using “0”, the number of “double feeds” generated when 1,000 sheets of A4 size paper were passed horizontally was measured. The number of double feeds that can withstand normal use is 3/1000 or less.

Regarding the suitability of the above electrophotographic transfer paper for ink-jet printing with a monochrome ink-jet printer, an ink-jet printer “BJ-” manufactured by Canon Inc. was used.
The printing quality of characters printed using "220JS" was evaluated by the following method.

<Feathering> The outer edges of the characters printed by the above-mentioned ink jet printer were evaluated by visual evaluation in six steps. The sample having no feathering was designated as 6, and the one in which the ink was blurred and characters could not be determined was designated as 1. As print quality that can withstand normal use,
4 or more.

<Print-through> Solid printing was carried out by the above-mentioned ink jet printer, and the degree of ink removal to the surface opposite to the surface on which the solid printing was printed was visually evaluated in six steps. The strike-through degree that can withstand normal use is 4 or more.

The evaluation results of the neutral rosin content, the content of the acid-soluble aluminum salt, the suitability for electrophotography, and the suitability for ink-jet printing of the electrophotographic transfer papers of the examples and comparative examples are summarized below.

[0072]

[Table 1]

Evaluation results: In Table 1 above, Examples 1 to 12
The electrophotographic transfer papers of Comparative Examples 1 to 5 were compared for electrophotographic suitability and inkjet suitability.

When comparing Examples 1 to 12 with Comparative Example 1 for electrophotographic suitability, it was found that using a neutral rosin sizing agent as an internal sizing agent was more effective than using AKD as an internal sizing agent. It can be seen that the toner fixability is good and the occurrence of double feeding is small.

In addition, when comparing Examples 1 to 8 and Comparative Examples 2 and 3 with respect to ink jet aptitude, if the content of neutral rosin is 0.15% or more, feathering occurs when printing with an ink jet printer. It can be seen that the strikethrough is good. In addition, the content of neutral rosin is 0.4
It is understood that when the content is 5% or more, the effect of improving feathering and strikethrough is saturated.

When Examples 2 to 5, 8, and 11 were compared with Comparative Examples 4 and 5, the content of the acid-soluble aluminum salt derived from the sulfate band even when the transfer paper contained neutral rosin. However, when it is not 0.40% or more, feathering and strike-through are poor. When Examples 2, 4, and 7 were compared with Examples 9, 10, and 11, when the content of the acid-soluble aluminum salt derived from the sulfate band was 1.50% or more, feathering and strike-through occurred. It can be seen that the improvement effect of saturates.

When Examples 2 and 12 were compared, when calcium carbonate was used as a filler or when kaolin was used, sufficient neutral rosin and acid-soluble aluminum salts derived from sulfate bands were found in the paper. , It is understood that feathering and strike-through are good.

[0078]

According to the above results, the transfer paper for electrophotography of the present invention was prepared by using a papermaking pulp slurry having a papermaking pH of 7.0 or more containing at least a filler, a neutral rosin sizing agent and a sulfate band. A photographic transfer paper, wherein the content of the neutral rosin sizing agent in the transfer paper is 0.15 to 0.4.
5% by weight, content of acid-soluble aluminum salt is 0.40
When the content is set to about 1.50% by weight, electrophotographic aptitude such as toner fixing property and paper feeding property is good, and feathering,
It is characterized by having excellent inkjet suitability such as no strikethrough.

Claims (1)

[Claims] 1. An electrophotographic transfer paper made by using a papermaking pulp slurry having a papermaking pH of at least 7.0 containing at least a filler, a neutral rosin sizing agent and a sulfuric acid band, wherein the transfer paper contains Content of the conductive rosin sizing agent is 0.1
Neutral electrophotographic transfer paper, characterized in that the content is 5 to 0.45% by weight and the content of an acid-soluble aluminum salt is 0.40 to 1.50% by weight.