JP3504809B2 - How to make pearlescent paper - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing pearlescent paper. More specifically, the pearl pigment coating layer is formed only on the convex portion of the convex portion of the textured paper, and the pearl pigment coating layer is not formed on the concave portion. Excellent designability and excellent printability. It relates to a method for producing pearlescent paper.

[0002]

2. Description of the Related Art Hitherto, various types of pearlescent paper have been proposed. For example, in Japanese Examined Patent Publication No. 39-29267, there is a method in which a basic lead carbonate-based pearl pigment is mixed with casein, latex, or another binder and coated on a base paper.
Further, Japanese Patent Publication No. 51-45682 discloses a method of providing a pearl pigment layer on the entire surface of a base paper having a large number of projections and depressions that are patterned and distributed, and Japanese Patent Publication No. 1-47597 discloses a base paper. Describes a method of sequentially providing an aqueous pigment coating layer, an aqueous pearl pigment coating layer and a water-soluble polymer substance surface treatment layer.

At present, pearlescent paper which emits pearly luster is manufactured by using a printing means. Such pearlescent paper is printed on paper with high surface smoothness, such as art paper or coated paper, by using an ink called "pearl ink", which contains pearl pigment and vehicle as main components, and forms a pattern. It is a thing.

The applicant of the present invention has proposed, in JP-A-5-222700, to provide a coating solution in which a pearl pigment is dispersed by using a spray device so as to form a dot pattern over the entire surface of the base paper. In the method according to this publication, it is possible to partially provide the pearl pigment coating layer as a dot pattern, but since the pearl pigment dispersion is sprayed,
It has been difficult to continuously obtain an arbitrary pearl pigment coating pattern.

At present, none of these pearlescent papers has a pearl pigment coated on the entire surface of the base paper or has a certain pattern formed on the base paper for spraying.

[0006]

Known pearl pigments are natural pearl pigments obtained from fish scales, basic lead carbonate, mica powder, titanium oxide-coated mica powder and the like.
The shape of each of these is flat, and a pearlescent appearance is exhibited by arranging them flat on the base paper.

As described above, the present pearlescent paper is
Pearl pigment is applied to the entire surface of the base paper, a base paper with high surface smoothness is printed with a pattern of pearl ink, or an irregular dot pattern is applied. It is not yet known that a regular pattern of layers is obtained.

The present invention has been made to solve these problems, and a pearl pigment coating layer can be easily formed on a convex pattern portion of a base paper having a concave and convex pattern by using a known coating device. It is intended to provide a method for producing a pearl pigment-coated paper that can be produced.

[0009]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention has a center line surface roughness of a base paper, a transfer pressure of a backing roll of a roll coater, a clearance between a gravure roll and a backing roll, and a pearl pigment coating liquid. As a result of diligent study on the concentration and viscosity of the above, the following was found.

That is, the base paper according to the present invention is JIS
From uneven pattern paper formed by parallel line groups or curve groups or their composite line groups having a center line average roughness of 5 to 100 μm measured by a stylus type surface roughness tester specified by B 0610 And the transfer pressure of the backing roll is 0.5 to 5 Kg / c using a coating device on the convex portion of the uneven pattern.
m ² and the clearance between the gravure roll and the backing roll is set to 1.0 to 1.1 times the paper thickness, the pearl pigment coating solution concentration is 10 to 50%, and the viscosity is 30 to 500 cp.
s and the pearl pigment coating layer is formed only on the convex portions of the textured paper.

Furthermore, the present inventors have found that in the binder used in the pearl pigment coating liquid, the glass transition point is 1 per 100 parts by weight of the water-dispersible resin having a glass transition point of 50 ° C. or higher.
It was found that by mixing 50 to 100 parts by weight of a water-dispersible resin at 0 to 30 ° C., a pearl pigment-coated paper which has practically sufficient adhesive strength and does not cause blocking can be obtained, and as JP-A-3-279494. Proposed. Also in the present invention, it is preferable to use this water-dispersible resin as a binder.

The water-dispersible resin generally has high tackiness when the glass transition point of the resin is low, and becomes low when the glass transition point is high. Therefore, in order to prevent blocking, it is sufficient to use a water-dispersible resin having a high glass transition point, but the use of this alone lowers the adhesive strength. On the other hand, when a water-dispersible resin having a low glass transition point is used alone, the adhesive force is obtained but the blocking problem occurs.

The main reason for using a binder having a glass transition point of 10 to 30 ° C. is to exhibit the fixation of the pigment. If the glass transition point is lower than 10 ° C., blocking is likely to occur, and if it exceeds 30 ° C., the film-forming property is deteriorated, and the sticking property is impaired, so that it is necessary to be within the above range.

Further, as a reason for using the binder at 50 ° C. or higher, the main purpose is to exert offset printing suitability. When the glass transition point is lower than 50 ° C., the emulsion particles form a uniform film after drying, which lowers the ink permeability. However, if the temperature is 50 ° C. or higher, the proportion of particles present in the film after drying is large, and the ink permeability is good.

As the method for producing pearlescent paper of the present invention, the transfer pressure of the backing roll is 0.5 to ⁵ Kg / cm ² and the clearance between the gravure roll and the backing roll is applied to the uneven pattern paper by using a coating device. Paper thickness 1.
A pearl pigment coating layer is formed with a setting of 0 to 1.1 times.

The pearlescent paper of the present invention may be further formed with a resin coating layer for the purpose of improving printability. Since the pearl pigment coating layer is partially coated on the base paper, when the pearl pigment coating layer is printed, the ink inking property differs between the pearl pigment coating portion and the non-coating portion. Therefore, the coloring properties and glossiness of the printing ink of the coated portion and the non-coated portion of the pearl pigment coating layer are expressed differently. In addition, the drying properties of the ink also differ.

Therefore, when it is desired to obtain uniform printing, the printing effect of printing can be made uniform by treating the resin coating layer. It is necessary to apply the resin coating layer on the entire surface, which makes the ink inking property uniform and improves the printability.

DETAILED DESCRIPTION OF THE INVENTION

The base paper is bleached softwood kraft pulp (NBK
P), hardwood bleached kraft pulp (LBKP), softwood bleached sulphite pulp (NBSP), thermomechanical pulp (TMP) and other wood pulps as the main components, and sizing agents, dyes and pigments, fillers, paper strengthening agents, and fixing agents. It is manufactured using a known paper machine with the addition of auxiliary materials for paper manufacturing such as a chemical agent.
At this time, other fibers for papermaking, such as straw pulp, seed hair fibers such as cotton, bast fibers such as San Tsubaki, Koto, leaf fibers such as hemp, synthetic fibers such as acrylic and vinylon, and semi-synthetic fibers such as rayon are used. It can also be used together.

On the other hand, the design paper, which is also called fancy paper, has a beautiful appearance, so that it is used as a cover for books, for publishing booklets, advertisement for pamphlets, posters, etc. It has been used for business purposes. One of the types of this design paper is "patterned paper" in which an uneven pattern is provided on the surface of the paper.

On the base paper, the center line average roughness measured by a stylus type surface roughness tester specified by JIS B 0610 is 5 to 5.
As a method of forming a group of parallel lines or a group of curves having a size of 100 μm or a complex line group thereof, a paper is once made into a paper, and a dry embossing method and a paper machine in which a pattern is engraved between rolls. The above can be roughly divided into the methods of applying a pattern until the paper is dried. As for the latter, as is known, a method in which a flocculant or the like is excessively added to a paper material to forcibly form a floc and the texture of the paper is largely destroyed, and then the paper is made A method of making paper after the fabric is significantly broken, a method of applying a pattern to the wet paper on the paper machine with an embossing roll, a method of transferring the blanket or canvas weave pattern to the wet paper on the paper machine, embossing on dry paper A method of imparting a pattern with a roll is adopted. As an example, it is possible to use a product that is modeled using a design steel roll and a steel flat roll, or a product that is modeled using two rubber design rolls.

The base paper has a center line average roughness of 5 measured by a stylus type surface roughness tester specified in JIS B 0610.
It is necessary that the thickness is 100 μm, and if it is 5 μm or less, a coating layer is formed not only on the convex portion but also on the concave portion, or the coating layer is obtained in a range close to the entire surface, and The purpose of coating cannot be achieved. on the other hand,
When the thickness is 100 μm or more, the feeling of fluffiness is conspicuous, and such a paper is not preferable because it is difficult to manufacture.

The pearl pigment coating liquid can be obtained by mixing a pearl pigment and a binder as main components. As the pearl pigment, natural pearl pigments obtained from fish scales, basic lead carbonate, mica powder, mica powder coated with titanium oxide and the like can be used, but since the selection range is widest,
It is preferable to use titanium oxide-coated mica powder.
The particle size of these is 5 to 150 μm, and more preferably 10
-100 μm is effective. The reason for this is that if the particle size is smaller than 5 μm, the luster is insufficient, and if the particle size exceeds 150 μm, the pearl pigment may fall off.

Examples of the binder include emulsion polymerization or emulsion copolymerization of acrylic acid or its ester, methacrylic acid or its ester, vinyl chloride, vinylidene chloride, vinyl acetate, acrylonitrile, butadiene, styrene or the like, or a carboxyl group or a hydroxyl group thereof. A water-dispersible resin (emulsion or latex) having a functional group introduced therein, and starch derivatives such as casein, starch, oxidized starch, dialdehyde starch, cationized starch, acetylated starch, phosphoric esterified starch, and hydroxyethylated starch, A natural or synthetic water-soluble resin such as polyvinyl alcohol is used alone or in combination of two or more kinds. At this time, a water-proofing agent, a coloring agent, a viscosity adjusting agent and the like can be used in combination as necessary.

The mixing ratio of the binder to the pearl pigment is usually 100 to 500 parts by weight with respect to 100 parts by weight of the pearl pigment. The amount of binder is 10
If the amount is less than 0 parts by weight, the strength of the coating layer will be insufficient, and if it exceeds 500 parts by weight, the pearl pigment will be unnecessarily covered with the binder and the pearlescent feeling will be insufficient, such being undesirable.

The water-dispersible resin means acrylic acid or its ester, methacrylic acid or its ester, vinyl chloride, vinylidene chloride, vinyl acetate, acrylonitrile,
It is an emulsion-dispersed or emulsion-polymerized water-dispersible emulsion (latex) of butadiene, styrene and the like, and also includes a polymer into which a functional group such as a carboxyl group or a hydroxyl group is introduced.

The pearl pigment coating layer is a pearl pigment coating liquid using a known coating device such as a roll coater, a gravure roll coater or a screen coater, which can measure the paint in advance and transfers the measured paint. It is obtained by coating the base paper. According to the studies by the present inventors, it is most preferable to use a gravure coater because a fine dot-shaped pattern can be easily obtained, the machine can be easily controlled, and the device can be easily designed. I got the result. This is because the clearance between the pick-up roll and the base paper, which is necessary to attach the pearl pigment coating liquid only to the convex portions of the uneven pattern, can be easily adjusted by adjusting the press pressure.

FIG. 3 is a sectional view showing an example of the gravure coater. The pearl pigment coating liquid 7 is adjusted to have a preferable concentration and viscosity, then weighed with a gravure roll 6 and the base paper 1 guided by the backing roll 4 comes into contact with the gravure roll 6 so that the unevenness of the base paper 1 is obtained. The pearl pigment coating liquid is transferred to the convex portions of the pattern.

At this time, the concentration of the pearl pigment coating solution is preferably in the range of 10 to 50%, more preferably 20 to 40%. The viscosity is preferably 30 to 500 cps. This is because by controlling in this range, an efficient drying condition can be set, which helps more suitable transferability of the coating liquid and prevention of dripping and flow after transfer. The concentration and viscosity of the pearl pigment coating liquid are not limited to the above-mentioned range, and are appropriately adjusted by each coating machine.

Then, the size of the pattern transferred onto the base paper 1 is determined by adjusting the transfer pressure of the backing roll 4. It is important to set a small pressure in order to reduce the transfer area, and to set a large pressure in order to increase the transfer area.

The transfer pressure of this backing roll is 0.5.
It is set in the range of up to 5 Kg / cm ² , but depending on the shape of the base paper pattern, there is a base paper that can be transferred only by the weight of the backing roll.

Further, in the case of a base paper with a clear patterning, the setting of the clearance between the gravure roll and the backing roll is also an important factor for pattern formation according to the thickness and shape of the base paper. The shape of the pattern paper is determined by adjusting the distance from the gravure roll and changing it appropriately. The clearance is set to 1.0 to 1.1 of the paper thickness.
A double range is preferable. If it is 1.0 times or less, the pearl pigment coating layer is formed more than necessary, and the object of the present invention cannot be achieved. On the other hand, if it is 1.1 times or more, it is difficult to form the pearl pigment coating layer on the base paper, which is not preferable.

The pattern-like pattern is the size of the base paper 10c.
It is desirable that the coating area is 5 to 50%, preferably 10 to 30% per m × 10 cm. The shape is mainly circular to elliptical, and in the case of a circle, the diameter is in the range of 0.1 to 3.0 mm, preferably 0.
It is preferably within the range of 5 to 2.0 mm. This is a preferable size for visually recognizing the shape.
The coating amount of pearl pigment is 1.0 to 1 in terms of solid content after drying.
0.0 g / m ^2, preferably from 2.0 to 6.0 g / m ^2. This is because if the coating amount is too small, the pearlescent feeling is insufficient, and if the coating amount is too large, the pearlescent feeling becomes excessive, giving uncomfortable feeling. Therefore, 2-5 g / m for small patterns
² , and in the case of a large pattern, 3 to 6 g / m ² is a more preferable coating amount.

Resin coating layer 3 for improving printability
Among the binders used in the above-mentioned pearl pigment coating liquid, those which do not cause blocking can be used. The water-dispersible resin is an emulsion-polymerized or emulsion-polymerized water-dispersible emulsion (latex) of the above-mentioned acrylic acid or its ester, methacrylic acid or its ester, vinyl chloride, vinylidene chloride, vinyl acetate, acrylonitrile, butadiene, styrene and the like. ), And a polymer having a functional group such as a carboxyl group or a hydroxyl group introduced therein is also included.

The coating amount of the resin coating layer is usually 1.0 to 10.0 g / m ² , preferably 2.0 to 10 in terms of solid after drying.
The coating amount is 5.0 g / m ² , and coating is performed using a known coating machine such as a roll coater, a gravure coater, a screen coater, an air knife coater, a blade coater, and a bar coater.

The water-dispersible resin used in the resin coating liquid has a glass transition point of 5 like the binder in the pearl pigment coating layer.
50 to 100 parts by weight of a water-dispersible resin having a glass transition point of 10 to 30 ° C. is added to 100 parts by weight of a water-dispersible resin at 0 ° C. or higher.

The reason why the binder having a glass transition point of 10 to 30 ° C. is used is to have the effect of further improving the offset printing suitability. Glass transition point is 1
By mixing the resin of 0 to 30 ° C., the resin layer is provided with appropriate softness, and the effect of improving the pick-up rate of the ink during printing is obtained.

The reason why the binder having a temperature of 50 ° C. or higher is used is that if the resin coating layer is formed only of the resin having the glass transition point of 10 to 30 ° C., blocking is likely to occur. Therefore, it is necessary to mix a resin having a high glass transition point of 50 ° C. or higher to prevent blocking. That is, by mixing the above-mentioned two resins, it is possible to improve the pick-up rate of ink and to simultaneously provide the effect of preventing blocking.

[0038]

EXAMPLES The present invention will be described in detail based on the following examples. Unless otherwise specified, parts by weight means dry parts, and g / m ² also means dry parts.

Example 1 JIS B with a basis weight of 157 g / m ² and a thickness of 0.190 mm
Base paper having a center line average roughness of 13 μm measured by a stylus-type surface roughness tester specified in 0610 (eg, “rock surface”,
Tokushu Tokushu Paper Co., Ltd. fancy paper), using the pearl pigment coating liquid of the following formulation, using the gravure coater of FIG.
Machine speed 50m / min, transfer pressure 2.0Kg /
The coating was applied on the peaks of the convex and concave patterns with a cm ² and a clearance of 0.2 mm, and then dried. The coating amount was 5 g / m ² , and the coated area was 20%.

[0040] Pearl pigment coating liquid particle size 40 [mu] m, titanium oxide-coated 28% of mica powder 100 parts by weight ( "Iriodin 101", Merck Japan Ltd.) acrylic emulsion 60 parts by weight of the glass transition point 50 ° C. ( “AE116”, manufactured by Japan Synthetic Rubber Co., Ltd. 30 parts by weight of acrylic emulsion having a glass transition point of 20 ° C. (“AE932”, manufactured by Japan Synthetic Rubber Co., Ltd.) 10 parts by weight of phosphorylated starch (“MS-4600”, Japan) Food Processing Co., Ltd.)

[0041]Example 2 Basis weight 105g / m²JIS B with a thickness of 0.125 mm
 Measured with a stylus-type surface roughness tester specified by 0610
Base paper with center line average roughness of 22 μm (eg
Tsu ", special paper manufacturing Co., Ltd. fancy paper)
The same pearl pigment coating liquid as in Example 1 was applied to the gravure coater of Fig. 2.
, Machine speed 50m / min, transfer pressure
0.5 kg / cm², Uneven with no clearance
It was dried after being applied to the convex-shaped peak portions. Coating amount is 2g
/ M²The coated area was 10%.

Example 3 JIS B with a basis weight of 105 g / m ² and a thickness of 0.125 mm
A base paper having a center line average roughness of 5 μm measured by a stylus type surface roughness tester specified in 0610 (eg, “Tant”,
The same pearl pigment coating liquid as in Example 1 was used for Fancy paper manufactured by Tokushu Paper Co., Ltd. using the gravure coater shown in FIG. 2, machine speed was 50 m / min, transfer pressure was 0.5K.
The coating was applied to the convex peaks of the concave and convex pattern under conditions of g / cm ² and no clearance, and then dried. The coating amount is 5 g / m ² ,
The coated area was 30%.

Example 4 The same pearl pigment coating liquid as in Example 1 was applied to the patterning paper of Example 1 using the gravure coater shown in FIG.
It was applied at 0 m / min, a transfer pressure of 2.0 Kg / cm ² , and a clearance of 0.2 mm on the peak portion of the uneven pattern and then dried. Coating amount is 5g / m ² , coating area is 20%
Met. Next, a resin coating solution having the following formulation was applied to the surface with an air knife coater at a coating amount of 5 g / m ² , and then dried.

Resin coating liquid Acrylic emulsion having a glass transition point of 50 ° C. 60 parts by weight (“AE116”, manufactured by Nippon Synthetic Rubber Co., Ltd.) 30 parts by weight of acrylic emulsion having a glass transition point of 20 ° C. (“AE932”, Japan Synthetic Rubber) 10 parts by weight of phosphorylated starch ("MS-4600", manufactured by Nippon Food Processing Co., Ltd.)

Comparative Example 1 The same pearl pigment coating liquid as in Example 1 was applied to a commercially available high-quality paper having a basis weight of 157 g / m ² and a thickness of 0.190 mm and a maximum depth of 1.8 μm. Using a gravure coater, machine speed 50m / min, transfer pressure 2.0Kg / cm
^2. Partial coating was attempted with a clearance of 0.2 mm, but the entire surface was coated and wavy coating unevenness was generated.
The coated paper was coated and then dried. The coating amount was 8 g / m ² , and the coated area was 100%.

Comparative Example 2 The same pearl pigment coating solution as in Example 1 was applied to commercially available coated paper having a basis weight of 105 g / m ² and a thickness of 0.125 mm and a maximum depth of 0.6 μm. Gravure coater, machine speed 50m / min, transfer pressure 0.5K
It was dried after coating under the conditions of g / cm ² and no clearance. The coating amount was 10 g / m ² and the coating area was 100%. Next, the resin coating liquid used in Example 3 was coated on the entire surface at a coating amount of 5 g / m ² using an air knife coater and then dried.

Table 1 shows the formulation and evaluation results of each example and comparative example. The evaluation is displayed in four grades of excellent, good, good and bad. The design is judged visually and the printability is IG
Solid print with Tack 30 ink with a T tester, the surface strength of the paper surface (peeling state), and an ink ink of offset process ink with an RI tester.
It was judged by observing the ink drying property and the printing ink gloss.

[0048]

[Table 1]

As described above, the pearly luster pattern paper of the present invention is constructed and has the following remarkable effects.

(1) The pattern on the surface can be clearly seen depending on the viewing angle, has an excellent design effect, and has good printability.

(2) It is possible to continuously obtain an arbitrary pearl pigment coating pattern.

(3) With the structure in which the pearl pigment coating layer is formed on the convex mountain portion of the concave-convex pattern paper, a design effect which has not been hitherto obtained can be exhibited. For example, a poster, a calendar, a cut-off cover of a book, a facing, a catalog. It can be suitably used for applications such as restaurants, menus, and greeting cards.

[Brief description of drawings]

FIG. 1 is an example in which a pearl pigment coating layer is formed on a convex mountain portion of an irregular pattern paper according to the present invention.

[Fig. 2] Example of providing a resin coating layer on pearlescent paper to improve printability

FIG. 3 is a cross-sectional view of a gravure coater when coating a convex mountain portion of a concave-convex pattern paper.

[Explanation of symbols]

1: Base paper (uneven pattern paper) 2: Pearl pigment coating layer 3: Resin coating layer 4: Backing roll 5: Doctor blade 6: Gravure roll 7: Pearl pigment coating liquid

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-279494 (JP, A) JP-A-4-97900 (JP, A) JP-A-5-222700 (JP, A) JP-A-8- 127111 (JP, A) JP-A-6-328027 (JP, A) JP-A-50-27838 (JP, A) JP-A-59-169576 (JP, A) JP-B-51-45682 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) D21H 11/00-27/42

Claims (3)

(57) [Claims] 1. When a pearl pigment coating layer is provided on a base paper having an uneven pattern by using a roll coater equipped with a gravure roll, (a) the base paper has a stylus-type surface roughness specified in JIS B 0610. The center line average roughness measured by the tester is 5
It is formed of parallel line groups or curved line groups of 100 μm or a composite line group thereof, and (b) the transfer pressure of the backing roll of the roll coater is 0.5 to 5 Kg / c.
m ² and the clearance between the gravure roll and the backing roll is set to 1.0 to 1.1 times the thickness of the base paper, (c)
A method for producing a pearlescent paper, characterized in that a pearl pigment coating layer is formed on a convex portion of an uneven pattern of a base paper, and an area of the pearl pigment coating layer occupying the base paper is 5 to 50%. 2. The pearl pigment coating layer comprises 100 to 500 parts by weight of a binder with respect to 100 parts by weight of a pearl pigment,
Further, as a component of the binder, the glass transition point is 10 with respect to 100 parts by weight of the water-dispersible resin having a glass transition point of 50 ° C. or higher.
The method for producing pearlescent paper according to claim 1, which comprises 50 to 100 parts by weight of a water-dispersible resin at -30 ° C. 3. A water-dispersible resin having a glass transition point of 10 to 30 ° C. with respect to 100 parts by weight of the water-dispersible resin having a glass transition point of 50 ° C. or more after providing the pearl pigment coating layer.
The method for producing pearlescent paper according to claim 1, wherein a resin coating layer composed of parts by weight is provided.