JP4908547B2 - Acid and water resistant paper sheet and method for producing the same - Google Patents

Description

  The present invention relates to an acid- and water-resistant paper sheet and a method for producing the same.

To date, many attempts have been made to add functionality to paper containing natural fibers.
For example, as a paper sheet with improved water and oil resistance, a water and oil resistant paper in which a synthetic resin or an emulsion thereof is applied to one or both sides of paper made of natural fibers is known (for example, see Patent Documents 1 to 3). .

In recent years, a method using a biodegradable natural resin in place of the synthetic resin has been studied in consideration of environmental problems.
For example, at least one surface of a pulp molded body or base material in which a biodegradable coating film made of polyester-based biodegradable plastic or shellac is formed on the inner surface or outer surface of a paper container main body, polyvinyl alcohol and shellac are used. A pulp molded body having a coating layer to be included is known (see, for example, Patent Document 4 or 5). Such a pulp molded article is excellent in water resistance.

Japanese Patent Laid-Open No. 9-3395 Japanese Patent Laid-Open No. 11-124792 JP 2006-28650 A JP 2002-105887 A JP 2004-256926 A

However, a paper sheet excellent in acid resistance and water resistance has not been developed yet.
Even if the conventional paper sheet including the water-resistant and oil-resistant paper described in Patent Documents 1 to 3 and the pulp molded body described in Patent Documents 4 and 5 is used, the water resistance is excellent, but the acid resistance is It is insufficient.

Moreover, in the artificial hatching of a rabbit, the spawned rabbit egg is disinfected by 2% formalin immersion, washed with running water and light brushing, and immersed in hydrochloric acid solution (3.5 to 12.0 N) for 1 hour.
For this reason, an acid- and water-resistant paper sheet having acid resistance and water resistance is required as an egg-laying mount.
In addition, when the conventional paper sheet mentioned above is used as an egg-laying mount, since acid resistance is not enough, paper will be damaged.

  This invention is made | formed in view of the said situation, and it aims at providing the acid-resistant water-resistant paper sheet which is excellent in acid resistance and water resistance, and its manufacturing method.

  The present inventors diligently studied to solve the above problems, and as a result, a cured wax-containing shellac obtained by curing a wax-containing shellac using a paper containing natural fibers having hydrogen bonds and a wax-containing shellac among shellacs. Surprisingly, when a predetermined amount was given to the inside of the paper, it was found that the above problems could be solved, and the present invention was completed.

That is, the present invention provides (1) an acid- and water-resistant paper sheet obtained by impregnating a wax containing shellac into a paper containing natural fibers and then curing the wax-containing shellac to form a cured wax- containing shellac. Is a mixture of dewaxed shellac and wax, the dewaxed shellac is obtained from a dissolved component when natural shellac and ethanol are mixed and centrifuged, and the wax is natural shellac. And ethanol are mixed, and the insoluble component when centrifuged is mixed with xylene and centrifuged again, and the amount of hardened wax-containing shellac applied is 4 to 59 μg / mm ³ for acid and water resistant It exists in a sex paper sheet.

The present invention resides in (2) the acid- and water-resistant paper sheet according to the above (1), wherein the applied amount of wax in the cured wax-containing shellac is 1 to 12 μg / mm ³ .

  The present invention resides in (3) the acid- and water-resistant paper sheet according to the above (1) or (2), wherein the wax-containing shellac is bleached with a bleaching solution containing hypochlorous acid.

In the present invention, (4) any one of the above (1) to (3), wherein the natural fibers are seed hair fibers, bast fibers, leaf fibers, cellulosic plant fibers, wool or protein animal fibers. In the acid- and water-resistant paper sheet.

The present invention resides in (5) the acid- and water-resistant paper sheet according to any one of the above (1) to (3), wherein the natural fiber is a wood fiber .

The present invention resides in the acid- and water-resistant paper sheet according to any one of (1) to (5) , wherein (6) the paper is Japanese paper.

This invention exists in the acid-resistant water-resistant paper sheet as described in any one of said (1)-(6) whose thickness is 0.2-0.6 mm .

The present invention resides in (8) the acid- and water-resistant paper sheet according to any one of the above (1) to (7), wherein the wax is granular.

  This invention exists in the acid-resistant water-resistant paper sheet as described in any one of said (1)-(8) used for the egg-laying mount of (9) rabbits.

The present invention is (10) the method for producing an acid- and water-resistant paper sheet according to any one of (1) to (7) above, wherein natural shellac and ethanol are mixed and dissolved when centrifuged. Mix the dewaxed shellac obtained from the ingredients with natural shellac and ethanol, mix the insoluble component when centrifuged, mix with xylene, and mix with the wax that is the insoluble component when centrifuged again. A wax-containing shellac is impregnated with a mixture of wax-containing shellac and ethanol to the inside of the paper containing natural fibers, and the wax-containing shellac attached to the paper is heated at a temperature of 150 to 190 ° C. for 30 to 60 minutes. The present invention resides in a method for producing an acid and water resistant paper sheet which is cured by heat treatment .

  This invention exists in the manufacturing method of the acid-resistant water-resistant paper sheet of said (10) description whose density | concentration of the wax-containing shellac in (11) liquid mixture is 3-77 mass%.

This invention exists in the manufacturing method of the acid-resistant water-resistant paper sheet as described in said (10) or (11) whose (12) hardening means is microwave irradiation.

This invention is (13) The manufacturing method of the acid-resistant water-resistant paper sheet as described in said (10) or (11) whose hardening means is microwave irradiation and the irradiated energy is 15-21 cal / cm < ² >. Exist.

The acid- and water-resistant paper sheet of the present invention uses paper containing dense natural fibers having hydrogen bonds, and the hardened wax-containing shellac obtained by curing the wax-containing shellac is applied to the inside of the paper. Invasion of water is suppressed, and damage due to acid hydrolysis is also suppressed.
Therefore, the acid-resistant and water-resistant paper sheet is excellent in acid resistance and water resistance.
In addition, the acid-resistant and water-resistant paper sheet can be prevented from being broken even when the paper is bent by setting the applied amount of the cured wax-containing shellac in the above range.
Furthermore, the acid- and water-resistant paper sheet is made of paper containing natural fibers and uses a cured wax-containing shellac obtained by curing wax-containing shellac, which is a natural thermosetting resin, and is therefore harmless to the human body. Excellent biodegradability.

In the acid-resistant water-resistant paper sheet, when the amount of wax applied in the cured wax-containing shellac is 1 to 12 μg / mm ³ , the water resistance is further improved.

  In the above acid-resistant and water-resistant paper sheet, if the wax-containing shellac is bleached with a bleaching solution containing hypochlorous acid, it is possible to separate the dyeing at the time of dyeing the paper by applying letters or patterns on the surface with wax. It becomes possible. In addition, when performing dyeing printing or the like, the compatibility with various colors is improved.

In the acid- and water-resistant paper sheet, if the wax-containing shellac is a mixture of dewaxed shellac and wax, the acid resistance and water resistance can be further improved by adjusting the blending of these. it can.
In particular, it is preferable that the dewaxed shellac is obtained from a dissolved component when natural shellac and ethanol are mixed and centrifuged.
The wax is preferably an insoluble component when natural shellac and ethanol are mixed and centrifuged, and natural shellac and ethanol are mixed, and the insoluble component when centrifuged is mixed with xylene, More preferably, it is an insoluble component when centrifuged again.

  In the acid-resistant water-resistant paper sheet, when the wax is granular, the acid resistance is further improved.

  The acid-resistant and water-resistant paper sheet is suitably used for a rabbit egg-laying mount. The acid-resistant and water-resistant paper sheet can be immersed in 2% formalin, which is generally used in the artificial hatching process of straw, washed with running water and light brushing, or immersed in a hydrochloric acid solution (3.5 to 12.0 N). Even if it is carried out, breakage of the paper is suppressed.

In the method for producing the acid- and water-resistant paper sheet, the mixed liquid composed of wax-containing shellac and ethanol is impregnated into the paper containing the natural fiber, so that the wax-containing shellac sufficiently penetrates into the paper. Then, the wax-containing shellac adhered to the paper is cured by the curing means, so that the gaps between the dense natural fibers (paper) are filled with the cured wax-containing shellac.
For this reason, the acid-resistant and water-resistant paper sheet obtained is excellent in acid resistance and water resistance because it prevents intrusion of moisture and acid, and damage due to acid hydrolysis is suppressed.
In addition, the method for producing the above acid- and water-resistant paper sheet uses paper containing natural fibers, wax-containing shellac that is a natural thermosetting resin, and ethanol that is harmless to the human body. Excellent in properties.

Here, the wax-containing shellac can be reliably cured when the curing means is a heat treatment and the conditions for the heat treatment are within the above range.
Further, when the curing means is microwave irradiation, the wax-containing shellac can be cured in a short time. In addition, it is preferable that the energy irradiated is 15-21 cal / cm < ² >.

  In the above method for producing an acid and water resistant paper sheet, when the concentration of the wax-containing shellac in the mixed solution is 3 to 77% by mass, the acid resistance and water resistance of the resulting acid and water resistant paper sheet are surely improved. This prevents the paper from being broken even if it is bent.

FIG. 1 is a cross-sectional view showing an embodiment of an acid / water resistant paper sheet according to the present invention. FIG. 2 is a diagram showing a testing machine used when measuring acid resistance and water resistance in Examples. FIG. 3 is a graph showing the results of acid resistance test 2 of the example. FIG. 4 is a graph showing the results of acid resistance test 3 of the example. FIG. 5 is a graph showing the results of the acid resistance test 4 of the example. FIG. 6 is a graph showing the results of acid resistance test 5 of the example. FIG. 7 is a graph showing the results of acid resistance test 6 of the example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

FIG. 1 is a cross-sectional view showing an embodiment of an acid / water resistant paper sheet according to the present invention.
As shown in FIG. 1, the acid- and water-resistant paper sheet 10 according to this embodiment is provided with a cured wax-containing shellac 2 obtained by curing a wax-containing shellac on the entire paper 1.

In the acid / water resistant paper sheet 10, the applied amount of the cured wax-containing shellac 2 is 4 to 59 μg / mm ³ . The applied amount is a value obtained by dividing the total mass of the wax-containing shellac 2 attached to the paper 1 having a predetermined size by the total volume of the paper 1.
When the applied amount of the cured wax-containing shellac 2 is less than 4 μg / mm ³ , the acid and water resistance becomes insufficient, and when the applied amount of the cured wax-containing shellac 2 exceeds 59 μg / mm ³ , A situation to avoid breaking occurs.

The acid-resistant and water-resistant paper sheet 10 preferably has a thickness of 0.2 to 0.6 mm.
When the thickness is less than 0.2 mm, the thickness tends to be easily damaged as compared with the case where the thickness is within the above range. When the thickness exceeds 0.6 mm, the thickness is within the above range. When the paper 1 is bent, the surface tends to be broken.

The paper 1 contains natural fibers having hydrogen bonds and is made from paper. The obtained paper 1 may be handmade Japanese paper, or may be Western paper made by mechanical and chemical treatment.
Among these, the paper 1 is preferably made of natural fibers from the viewpoint of easy penetration of the wax-containing shellac 2, and is preferably Japanese paper from the viewpoint of water resistance.

Examples of the natural fibers include seed hair fibers such as cotton, bast fibers such as Mitsumata and Kozo, leaf fibers such as Manila hemp, cellulosic plant fibers such as wood fibers, and protein-based animal fibers such as wool and silk. It is done.
Among these, the natural fiber is preferably a cellulosic plant fiber from the viewpoint of adhesiveness with the wax-containing shellac, and particularly preferably a wood fiber.

The wax-containing shellac before curing is preferably 3 to 77% by mass, more preferably 3.9 to 59.1% by mass, and more preferably 9 to 9% by mass, including the ethanol-insoluble fine granules. More preferably, it is 40 mass%.
When the wax content is less than 3% by mass, compared to the case where the wax content is within the above range, the acid and water resistance tends to be insufficient, and the wax content is 77% by mass. When it exceeds, when the content rate of a wax exists in the said range, when the paper 1 is bent, it exists in the tendency for the surface to crack.

The applied amount of wax in the cured wax-containing shellac 2 is preferably 1 to 12 μg / mm ³ .
When the applied amount of the wax is less than 1 μg / mm ³ , compared to the case where the applied amount of the wax is within the above range, the acid water resistance tends to be insufficient, and the applied amount of the wax is 12 μg / mm. ^If it exceeds ³ , the surface of the paper 1 tends to be broken when the paper 1 is bent, as compared with the case where the applied amount of wax is within the above range. In addition, this provision amount is synonymous with the provision amount mentioned above.

In addition, the wax content in the wax-containing shellac before curing described above is 3 to 77% by mass, and the applied amount of the wax in the cured wax-containing shellac 2 is 1 to 12 μg / mm ^3. More preferred.

The wax-containing shellac before curing is preferably a mixture of dewaxed shellac and wax.
In this case, acid resistance and water resistance can be further improved by adjusting the blending ratio of dewaxed shellac and wax.

Here, it is preferable that the dewaxed shellac is obtained from a dissolved component when natural shellac and ethanol are mixed and centrifuged.
The wax is preferably a wax of an insoluble component when natural shellac and ethanol are mixed and centrifuged (hereinafter referred to as “first wax” for convenience), and natural shellac and ethanol are mixed. The insoluble component when centrifuged is more preferably a wax of an insoluble component when mixed with xylene and centrifuged again (hereinafter referred to as “second wax” for convenience).
When the wax is the first wax, since it is derived from natural shellac, compatibility with dewaxed shellac is excellent. Moreover, when it is a 2nd wax, although a reason is not certain, acid resistance improves remarkably.

The shape of the wax is not particularly limited, but is preferably granular.
In this case, since the granular wax functions as a filler and a sizing agent, the acid resistance is further improved.
Therefore, in the acid / water resistant paper sheet 10 of the present invention, the wax-containing shellac is particularly preferably a mixture of the dewaxed shellac and the granular second wax.

The wax-containing shellac before curing may be bleached with a bleaching solution containing hypochlorous acid.
In this case, letters and patterns can be applied to the surface of the acid and water resistant paper sheet 10. In addition, compatibility with dyeing and printing is good.

In the acid- and water-resistant paper sheet 10, the cured wax-containing shellac 2 may contain an additive.
Such additives include sizing agents, binders, coating agents, fillers, dispersants, wetting agents, lubricants, preservatives, chelating agents, pH adjusting agents, flame retardants and the like.

The acid- and water-resistant paper sheet 10 according to the present embodiment is suitably used for applications such as a spawning mount for rabbits and wallpaper.
Among these, the acid-resistant and water-resistant paper sheet 10 is suitably used for salmon spawning mount.
In this case, the acid- and water-resistant paper sheet 10 is immersed in 2% formalin, washed with running water and light brushing, or immersed in hydrochloric acid solution (3.5 to 12.0 N). Damage is suppressed.

As described above, the acid- and water-resistant paper sheet 10 according to the present embodiment uses the paper 1 containing dense natural fibers having hydrogen bonds, and the cured wax-containing shellac 2 obtained by curing the wax-containing shellac is contained therein. Since it is given, the penetration of moisture and acid is suppressed, and damage due to acid hydrolysis is also suppressed.
Therefore, the acid and water resistant paper sheet 10 is excellent in acid resistance and water resistance. If the wax-containing shellac remains uncured, sufficient acid resistance and water resistance cannot be obtained.
Moreover, the acid-resistant water-resistant paper sheet 10 is prevented from being broken even when the paper 1 is bent, by setting the application amount of the wax-containing shellac 2 in the above range.
Furthermore, the acid- and water-resistant paper sheet 10 uses paper 1 containing natural fibers and uses a wax-containing shellac 2 that is a natural thermosetting resin, so it is harmless to the human body and biodegradable. Also excellent.

Next, the manufacturing method of the acid-resistant water-resistant paper sheet 10 is demonstrated.
In the method for producing the acid- and water-resistant paper sheet 10 according to the present embodiment, dewaxed shellac and wax are mixed to produce a wax-containing shellac, and the resulting mixture of wax-containing shellac and ethanol is mixed with natural fibers. The inside of the containing paper 1 is impregnated, and the wax-containing shellac attached to the paper 1 is cured by a curing means.

First, natural shellac and ethanol are mixed and centrifuged. Then, a dissolved component in which the dewaxed shellac component is dissolved and an insoluble component in which the first wax is precipitated are obtained.
Then, the dissolved component is taken out and ethanol is removed to obtain a dewaxed shellac, and the insoluble component is taken out to obtain the first wax.

Next, the insoluble component in which the first wax is precipitated and xylene are mixed and centrifuged. As a result, a dissolved component and an insoluble component in which the second wax is precipitated are obtained.
And an insoluble component is taken out and a 2nd wax is obtained.

Next, a mixed solution is prepared.
Such a mixed solution can be obtained by mixing wax-containing shellac obtained by mixing dewaxed shellac and wax (first wax or second wax) with ethanol. At this time, the concentration of the wax-containing shellac in the mixed solution is preferably 56 to 103 g / liter when the wax contains 5% by mass.
When the concentration of the wax-containing shellac is less than 56 g / liter, the acid resistance and the water resistance tend to be insufficient as compared with the case where the amount of the applied wax is within the above range. When it exceeds 103 g / liter, the surface tends to be broken when the paper is bent, compared to the case where the concentration of the wax-containing shellac is within the above range.

Next, paper 1 containing natural fibers is impregnated with the mixed solution. That is, the mixed liquid penetrates into the paper 1. Then, it is dried.
Then, the wax-containing shellac adhered to the paper 1 is cured by a curing means.
Examples of such curing means include heat treatment and microwave irradiation. Note that microwave irradiation may be performed while heat treatment is performed.

When the curing means is a heat treatment, the heat treatment conditions are preferably a temperature of 150 to 190 ° C. and a time of 30 to 60 minutes.
When the temperature is less than 150 ° C., the wax-containing shellac tends to not be sufficiently cured as compared with the case where the temperature is within the above range, and when the temperature exceeds 190 ° C., the temperature is within the above range. In comparison with the above, the obtained acid- and water-resistant paper sheet is yellowed, and if the paper is bent, the surface may be broken.
Further, when the time is less than 30 minutes, the wax-containing shellac tends to be not sufficiently cured as compared with the case where the time is within the above range, and even when the time exceeds 60 minutes, the degree of hardening of the wax-containing shellac. Tend not to improve.

When the curing means is a microwave, the amount of energy applied to the paper 1 impregnated with the mixed solution may be 4 to 23 cal / cm ² .
In this case, the wax-containing shellac can be cured in a short time, and the curing can be performed without providing a device for heating, so that the productivity of the acid / water resistant paper sheet is improved.

At this time, it is preferable that the energy irradiation amount is 15 to 21 cal / cm ² .
When the energy irradiation amount is less than 15 cal / cm ² , the strength tends to be lower than when the energy irradiation amount is within the above range, and when the energy irradiation amount exceeds 21 cal / cm ^2. As compared with the case where the irradiation amount of energy is within the above range, although the curing is strong and the acid water resistance is high, the paper tends to be brittle with respect to bending.

  For example, as a method of applying such energy, microwave irradiation conditions are as follows: frequency 2400-2500 MHz, radiation source output 500 W, distance from the radiation source to the paper 15-17 cm, distance 1 to separate the paper from the base ˜2 cm, time 30 to 120 seconds may be used.

As described above, the method for producing the acid- and water-resistant paper sheet 10 impregnates the mixed liquid composed of wax-containing shellac and ethanol up to the inside of the paper 1 containing natural fibers, so that the wax-containing shellac is inside the paper. Until fully penetrated.
Then, the wax-containing shellac adhered to the paper 1 is cured by the curing means, so that the gaps between the dense natural fibers (paper) are filled with the cured wax-containing shellac 2.
For this reason, the acid-resistant water-resistant paper sheet 10 obtained is excellent in acid resistance and water resistance because it suppresses intrusion of moisture and acid, and damage due to acid hydrolysis is suppressed.
In addition, the method for producing the above acid- and water-resistant paper sheet uses paper containing natural fibers, wax-containing shellac that is a natural thermosetting resin, and ethanol that is harmless to the human body. Excellent in properties.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

[Acid resistance test 1]
Example 1
A wax-containing shellac having a wax content of 5% by mass was mixed with ethanol to obtain a mixed solution having a wax-containing shellac concentration of 30 g / liter in ethanol.
This was impregnated with Kent paper (thickness: 0.35 mm) containing natural fibers, dried, and heat-treated at 170 ° C. for 30 minutes to cure the wax-containing shellac. Then, it stood to cool at room temperature and obtained the sample which consists of an acid-resistant water-resistant paper sheet.

(Comparative Example 1)
A sample was obtained in the same manner as in Example 1 except that no wax-containing shellac was used.

(Comparative Example 2)
A sample was obtained in the same manner as in Example 1 except that the heat treatment was not performed (the wax-containing shellac was not cured).

(Comparative Example 3)
A sample was obtained in the same manner as in Example 1 except that gohsenol (polyvinyl alcohol) was used instead of wax-containing shellac.

(Evaluation methods)
The samples obtained in Example 1 and Comparative Examples 1 to 3 were immersed in 2% formalin for 1 hour, washed with running water for 15 minutes, and then air-dried. After drying, it was immersed in dilute hydrochloric acid having a specific gravity of 1.1 (25 ° C.) for 1 hour, and the subsequent state was evaluated visually. Evaluation was also made on the use of cardboard (including natural fibers), cardboard (including natural fibers), and copy paper (not including natural fibers) instead of Kent paper. Also, the amount applied to Kent paper is 16 μg / mm ³ , the amount applied to thick paper (thickness: 0.32 mm) is 16 μg / mm ^3, and the amount applied to cardboard (thickness: 0.62 mm) is 16 μg. / Mm ^3, and the amount applied to the copy paper (thickness: 0.1 mm) was 16 μg / mm ³ respectively.
The obtained results are shown in Table 1. In the table, “no change” means that there is no change before and after the acid resistance test, and “breakage” means that the sample is broken after the acid resistance test. Although the copy paper of Example 1 and the cardboard of Comparative Example 3 were strong, they could not prevent the penetration of hydrochloric acid, and it took a considerable time to remove the hydrochloric acid by washing with water.

  From the results in Table 1, it was confirmed that the acid resistance and water resistance were improved by the combination of paper containing natural fibers and wax-containing shellac.

[Acid resistance test 2]
(Example 2)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 110 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

Example 3
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 120 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

Example 4
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 130 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 5)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 140 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 6)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 150 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 7)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 160 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 8)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 180 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

Example 9
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 1 except that the heat treatment temperature was 190 ° C. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Evaluation methods)
The samples obtained in Examples 1 to 9 and Comparative Example 2 were immersed in 2% formalin for 1 hour, washed with running water for 15 minutes, and then air-dried. After drying, it was immersed in dilute hydrochloric acid having a specific gravity of 1.1 (25 ° C.) for 1 hour, and then washed in running water for 15 minutes.
And the acid resistance and water resistance were tested with the test apparatus shown in FIG.
Specifically, as shown in FIG. 2, the sample 14 pulled up from the water is placed on the movable table 11 while being wet, and the friction body 13 connected to the arm 12 is brought into contact with the sample 14. Then, the movable table 11 was slid. As the friction body 13, a natural rubber sponge having a size of 2.5 cm square was used, and a weight of 603 g was applied in the vertical direction from above. The movable table 11 was slid back and forth at a speed of 170 times per minute, and the operation length was 3.5 cm. Furthermore, the number of reciprocations was 100.

Thereafter, each sample was dried, placed in a light box provided with a fluorescent lamp, and black and white photography was performed with a digital camera. Then, the density of each pixel of the digital image was measured in the range of density values from 0 (white) to 255 (black), and the average value was calculated.
The value of the non-weared portion of the sample was set to 1, the case where the hole was opened due to wear was set to 0, the average value obtained was standardized, and the standardized value was defined as acid resistance.
A graph of the obtained results (acid resistance and water resistance) is shown in FIG.

From the result of FIG. 3, the improvement of the abrasion resistance (acid resistance and water resistance) after acid treatment was recognized notably in the range of the heat treatment temperatures of 110 to 190 ° C. in Examples 1 to 9. In particular, when the temperature is 150 to 190 ° C., it can be said that the acid resistance and water resistance are sufficiently excellent.
On the other hand, when the temperature of the heat treatment in Examples 1, 8 and 9 was 170 ° C. or higher, the sample was more cured as the temperature was higher, and when it exceeded 190 ° C., the paper tended to be cured. In a test conducted in advance, when the heat treatment temperature was 200 ° C., the obtained sample was more cured, and when the paper was bent, there were cases where more cracks or tears occurred.

[Acid resistance test 3]
(Example 10)
A sample was obtained in the same manner as in Example 1 except that a wax-containing decolorized shellac obtained by decolorizing the wax-containing shellac with hypochlorous acid was used instead of the wax-containing shellac. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Comparative Example 4)
A sample was obtained in the same manner as in Example 1 except that dewaxed shellac having a wax content of 0% by mass was used instead of the wax-containing shellac having a wax content of 5% by mass. The amount of dewaxed shellac applied was 16 μg / mm ³ .

(Evaluation methods)
The samples obtained in Examples 6 and 10 and Comparative Examples 1 and 4 were measured for acid resistance and water resistance in the same manner as in acid resistance test 2.
However, the value of the paper thickness of Example 6 was set to 1, the case where it was worn and a hole was opened was set to 0, the average value obtained was standardized, and the standardized value was defined as acid resistance.
A graph of the obtained results (acid resistance and water resistance) is shown in FIG.

From the results of FIG. 4, the samples in Examples 6 and 10 were not so permeated with hydrochloric acid solution, and were excellent in acid resistance and water resistance.
On the other hand, the sample in Comparative Example 1 was torn and had a hole. The sample in Comparative Example 4 was inferior in acid resistance and water resistance than the samples in Example 6 and Example 10.
Moreover, since the sample in Comparative Example 4 does not contain a wax that functions as a filler and sizing agent having water repellency, hydrochloric acid permeates and sinks into the paper, and the removal of hydrochloric acid during washing is caused by the permeation. Because it was bad, it was unsuitable as a spawning mount.

[Acid resistance test 4]
(Examples 11 to 15)
Kent paper (thickness) containing natural fibers, in which dewaxed shellac having a wax content of 0% by mass and wax extracted from natural shellac were separately dissolved in ethanol to give the coating amount shown in Table 2 below. : 0.35 mm).
Then, it dried and heat-processed for 30 minutes at 170 degreeC, and the wax-containing shellac was hardened. And it stood to cool at room temperature, and obtained the sample which consists of an acid-resistant water-resistant paper sheet.

(Evaluation methods)
The samples obtained in Examples 11 to 15 and Comparative Example 4 were the same as the evaluation method in the acid resistance test 2 except that a 2.5 cm square natural rubber plate was used as the friction body 13 shown in FIG. Thus, acid resistance and water resistance were measured.
A graph of the obtained results (acid resistance and water resistance) is shown in FIG.

From the results of FIG. 5, when the application amount of wax and dewaxed shellac (total density) is 16 μg / mm ³ , the acid resistance and the resistance of wax are 1.4 μg / mm ³ (wax ratio 9 % by mass). It was found that the water resistance was sufficiently exhibited, and the acid resistance and water resistance were reliably exhibited at 2.9 μg / mm ³ or more. In addition, it was in the tendency for paper to harden as it was 12.3 microgram / mm < ³ > (wax | wax ratio 77 mass%) or more.

[Acid resistance test 5]
(Examples 16 to 19)
Kent paper (thickness) containing natural fibers, in which dewaxed shellac having a wax content of 0% by mass and wax extracted from natural shellac were separately dissolved in ethanol to give the coating amount shown in Table 3 below. : 0.35 mm), followed by drying and heat treatment at 170 ° C. for 30 minutes to cure the wax-containing shellac. Then, it stood to cool at room temperature and obtained the sample which consists of an acid-resistant water-resistant paper sheet.

(Evaluation methods)
The samples obtained in Examples 16 to 19 were measured for acid resistance and water resistance in the same manner as in the evaluation method in acid resistance test 4.
FIG. 6 shows a graph (scatter diagram) of the obtained results (acid resistance and water resistance).

From the results shown in FIG. 6, the acid resistance and water resistance increase almost linearly up to 25.1 μg / mm ³ of the wax-containing shellac, but the strength exceeds the increase of the wax-containing shellac. The increase in is less.
When the applied amount of wax-containing shellac is 59.1 μg / mm ³ , the paper may be cured.
Moreover, when the amount of wax-containing shellac imparting the strength of existing paper was calculated using the approximate curve, it was about 3.9 μg / mm ³ .

[Acid resistance test 6]
(Example 20)
Instead of heat treatment, a microwave with a frequency of 2450 MHz and a radiation source output of 500 W was used, and it was made of an acid- and water-resistant paper sheet in the same manner as in Example 1 except that it was cured with an energy of 4 cal / cm ^2. A sample was obtained. The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 21)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 6 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 22)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 8 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 23)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 10 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 24)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 12 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 25)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 13 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 26)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 15 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 27)
A sample composed of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 17 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 28)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 19 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 29)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 21 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Example 30)
A sample made of an acid- and water-resistant paper sheet was obtained in the same manner as in Example 20 except that the energy irradiation amount was 23 cal / cm ² . The amount of wax-containing shellac applied was 16 μg / mm ³ .

(Evaluation methods)
The samples obtained in Examples 20 to 30 were measured for acid resistance and water resistance in the same manner as in the acid resistance test 4 except that the number of reciprocations of the friction body 13 shown in FIG. did.
A graph of the obtained results (acid resistance and water resistance) is shown in FIG.

From the result of FIG. 7, the intensity increased when the irradiation amount of energy given by electromagnetic waves was 15 cal / cm ² or more. And when energy amount exceeded 21 cal / cm < ² >, hardening became strong and there existed acid-water resistance, but paper became extremely brittle with respect to bending.

DESCRIPTION OF SYMBOLS 1 ... Paper 2 ... Hardened wax-containing shellac 10 ... Acid-resistant water-resistant paper sheet 11 ... Movable table 12 ... Arm 13 ... Friction body 14 ... Sample

Claims (13)

The paper containing natural fiber, after impregnation with含蝋shellac, curing the含蝋shellac, a acid water-resistant paper sheet was cured含蝋shellac,
The wax-containing shellac is a mixture of dewaxed shellac and wax,
The dewaxed shellac is obtained from a dissolved component when natural shellac and ethanol are mixed and centrifuged.
The wax is an insoluble component when natural shellac and ethanol are mixed and centrifuged and mixed with xylene and centrifuged again,
An acid- and water-resistant paper sheet having an applied amount of the cured wax-containing shellac of 4 to 59 μg / mm ³ . The acid-resistant and water-resistant paper sheet according to claim 1, wherein the applied amount of wax in the cured wax-containing shellac is 1 to 12 μg / mm ³ .   The acid- and water-resistant paper sheet according to claim 1 or 2, wherein the wax-containing shellac is bleached with a bleaching solution containing hypochlorous acid. The acid-resistant and water-resistant paper sheet according to any one of claims 1 to 3, wherein the natural fiber is seed hair fiber, bast fiber, leaf fiber, cellulosic plant fiber, wool, or protein animal fiber . The acid- and water-resistant paper sheet according to any one of claims 1 to 3 , wherein the natural fiber is a wood fiber . The acid- and water-resistant paper sheet according to any one of claims 1 to 5 , wherein the paper is Japanese paper. The acid- and water-resistant paper sheet according to any one of claims 1 to 6, which has a thickness of 0.2 to 0.6 mm . The acid- and water-resistant paper sheet according to any one of claims 1 to 7, wherein the wax is granular.   The acid- and water-resistant paper sheet according to any one of claims 1 to 8, which is used for a rabbit egg-laying mount. A method for producing an acid and water resistant paper sheet according to any one of claims 1 to 9,
Dewaxed shellac obtained from dissolved components when natural shellac and ethanol are mixed and centrifuged;
Natural shellac and ethanol are mixed and insoluble components when centrifuged, xylene and wax that is insoluble components when centrifuged again, and
To make waxy shellac,
Impregnating a mixture of wax-containing shellac and ethanol into the paper containing natural fibers,
A method for producing an acid- and water-resistant paper sheet, wherein the wax-containing shellac adhered to the paper is cured by a heat treatment at a temperature of 150 to 190 ° C. for 30 to 60 minutes .   The method for producing an acid- and water-resistant paper sheet according to claim 10, wherein the concentration of the wax-containing shellac in the mixed solution is 3 to 77 mass%.   The method for producing an acid- and water-resistant paper sheet according to claim 10 or 11, wherein the curing means is microwave irradiation. Wherein the curing means is a microwave radiation, acid water-resistant paper sheet manufacturing method according to claim 10 or 11 energy irradiated is 15~21cal / cm ^2.

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