JPS59219751A - Method for matting recording material - Google Patents

Abstract

PURPOSE:To enhance matting effect by electrostatically attaching a coating soln. dissolving or dispersing a resin and contg. a solvent having a b.p. of a specified temp. or higher in a state of fine droplets onto the surface or the reverse face of a recording material, such as a photosensitive lithographic plate, and drying it to form a matted material. CONSTITUTION:A matting coating soln. is obtained by adding a water-soluble solvent having a b.p. of <=130 deg.C, such as ethylene glycol, ethylene glycol monomethyl ether acetate, or triethylene glycol to a latex of vinylidene-acrylate or styrene-butadiene copolymer or the like, or said latex contg. inorg. microparticles, such as carbon black or colloidal silica. The obtained coating soln. is attached in fine droplets onto the surface or the reverse face of a photosensitive printing plate or a magnetic tape by the rotary atomizing type electrostatic coating method or the like, and dried and heat hardened. The resin is strongly bonded and superior matting effect is obtained by containing a high boiling solvent and preventing blocking of a nozzle and the loss of adhesion due to too rapid drying before attachment of the coating soln.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for matting the front and/or back side of a recording material.

Conventionally, there have been a wide variety of techniques for manufacturing recording materials, one of which is to matte the front and back surfaces of photographic materials to prevent static electricity, prevent adhesion between photographic materials, and improve vacuum adhesion. is being carried out. For example, when conventionally, when forming an image on a photographic light-sensitive material, a film base plate is placed on the light-sensitive material in the exposure process, and when the light is exposed through the film base plate, the surface of the light-sensitive layer of the light-sensitive material is It is necessary to expose the rolled film original plates in complete contact with each other to avoid blurring of the exposed image due to the gap between them. For this reason, generally a vacuum printing frame is used, and the photosensitive material and film base plate are stacked and placed between the glass plate and rubber sheet of the printing frame, and a vacuum is created between the glass plate and the rubber sheet to bring them into close contact. (Hereinafter, this method is referred to as the vacuum adhesion method).
, No. 102, it is thought that by providing a minute G-turn consisting of a coated part and a non-coated part on the photosensitive layer, the photosensitive layer can be matted and the vacuum adhesion time can be significantly shortened. It was implemented. For example, the formation of minute patterns (matting) on this photographic photosensitive layer is carried out by JP-A-Sho! /-9'A40 Publication and Unexamined Patent Application Publication No. gjOj
No., Tokukai Akira! There is a method described in publications such as Fj-/2ri7φ. In recent years, so-called double-sided photographic materials, in which photosensitive layers are provided on both sides of the support, have become extremely popular among photographic materials. As described in the publication, a fine ξ turn is applied to the surfaces of both photosensitive layers using a gravure coating method (if a turn is to be provided, a fine ξ turn is first applied to one surface), dried, and then applied to the other surface. The minute pattern has to be applied and dried, and this series of equipment is quite large.Moreover, the area where the minute pattern is applied on the back side provided by the above method is not the same size as the desired size. During the process up to cutting, the material is often rubbed by the conveyance rollers, resulting in peeling and cracking, and when exposing the photosensitive layer on the back side, the vacuum adhesion time is longer than that on the front side. There was a drawback.

In addition, in the exposure process, there is a problem that the coated part of the micro pattern on the back side that will be exposed later is compressed and crushed by the printer during vacuum exposure on the front side, and it takes a long time to vacuum when exposing the back side. Ta. In addition, in the Japanese Patent Application Laid-open No. 2003-01-1996, in order to solve the problem that the coating layer that improves vacuum adhesion stains the original film,
A method has been proposed in which a waxy or finely powdered resin with mold releasability is dispersed in a low-boiling point M solvent and applied by air spray, but this coating layer has poor adhesion to the surface of the photosensitive printing plate. Because it is weak, it easily falls off, and there is still the same problem as mentioned above. Moreover, the use of organic solvents is not preferable from the viewpoint of safety during production. Furthermore, Japanese Patent Application Laid-Open No. 2003-120007-2 discloses a method of applying solid powder to a thin cloth and fixing it onto a photosensitive printing plate using heat. In this case, there is a problem that the matte layer on one side is crushed when it is conveyed by rollers after heat fusion and before it is cooled.On the other hand, conveying without using rollers
Difficult to handle. Furthermore, in order to make powder, the resin must be crushed and dispersed, resulting in high costs. Furthermore, Tokukai Akira! 1t-10/RIRI discloses a method for uniformly dispersing and depositing solid powder onto the surface of a continuously running photosensitive printing plate.
Powder feeding device, ejector, distributor,
A cyclone or the like is required, and the equipment is quite complex and large-scale. Moreover, in the case of a double-sided type photosensitive printing plate, the solid powder often falls off when the photosensitive printing plate is transported after being simultaneously deposited with the solid powder.

Tokukaisho! to solve these problems! 7-3171
Publication No. 1g discloses a method in which an aqueous solution in which a resin is dissolved or dispersed is sprayed onto the surface of a photosensitive printing plate having a photosensitive layer on a support, and then dried. Although the performance of the mat is very good in this method, there are some drawbacks in terms of suitability for production. When using Tsuma Shear Spray, the adhesion rate of fine droplets is very low (approximately 10%).
), the unattached droplets contaminate the inside of the coating chamber as overspray, and in extreme cases, they end up adhering to the plate being coated as unnecessary resin lumps. In order to reduce this overspray, an electrostatic coating method can be considered (adhesion rate of about 0% or more).

However, when applying an aqueous liquid by electrostatic coating, there are the following problems. First, in the case of the electrostatic coating method, fine droplets are electrostatically attached to the surface of the object to be coated. Very small particles have a small contact area and weak adhesion, and in the extreme, they end up merely being electrostatically attached to the surface. As a result, if the photosensitive material is transported while being in contact with a roll, etc., the adhered particles will fall off, making it impossible to achieve the desired shortening of the vacuum adhesion time, which is the same as the problem with the above-mentioned method. This results in contamination. Furthermore, in the case of a bell type or a disc type, the aqueous liquid dries in areas where the liquid flow of the thin film on the bell or disc is poor, resulting in resin precipitate, which inhibits atomization and prevents the precipitated resin from being covered. It may adhere to painted objects.

These are examples of improving the vacuum adhesion of photographic materials, but matting of photographic materials can also be used to prevent static electricity build-up,
Matting is applied to prevent adhesion and adhesion between photographic light-sensitive materials, and the portion to be matted is not limited to the surface of the photosensitive layer, but may also be applied to the back surface. Matting performed for these purposes also has the same problems as the above-mentioned case for improving vacuum adhesion.

Magnetic recording materials may also need to be matted. In recent years, magnetic recording tapes have tended to become smoother. Therefore, when a magnetic tape is run by a pressure roller in a magnetic recording/reproducing device, a problem arises in that the running performance is deteriorated. Therefore, a mat is provided on the back side of the magnetic tape in order to suppress the deterioration of the tape's running properties. Furthermore, in the case of magnetic sheets, etc., it is thought that in the future there will be a device that handles a large number of stacked sheets, and in that case, in order to prevent the stacked magnetic sheets from sticking together due to adhesiveness or generation of static electricity, It is effective to provide a mat layer on the back side.

The present inventors improved the technique of static painting as a means of matting, applied this to solve the problems of the conventional method as described above, and studied to develop a new method. and discovered the present invention.

An object of the present invention is to provide a method in which fine droplets of a coating liquid in which a resin is dissolved or dispersed are electrostatically flown and adhered to the front or back surface of a recording material to form a mat. The object of the present invention is to provide a method for firmly adhering materials so that they do not fall off during handling.

An object of the present invention is to provide a method for making fine droplets of a coating liquid in which a resin is dissolved or dispersed statically fly in a V-section and adhere to the front or back surface of a recording material to form a mat. The object of the present invention is to provide a method that prevents resin precipitation and allows stable production over a long period of time.

Another object of the present invention is to increase the matte particles formed from the adhered droplets by electrostatically flying fine droplets and causing them to adhere, and by incorporating a solvent with a boiling point of 1300C or higher into the coating liquid. An object of the present invention is to provide a method for matting a recording material that can control the shape and shape of the recording material and can be carried out continuously.

The present invention achieves the above-mentioned objectives, and its structure is to electrostatically attach several fine drops of a coating Xa solution in which a resin is dissolved or dispersed to the front and/or back surface of a recording material and dry it. In the method of matting the surface by
This method is characterized in that the coating liquid contains a solvent having a boiling point of 1300C or higher.

The present invention will be explained in detail below.

First, the recording material in the present invention basically has a recording layer provided on a support, and the recording layer may include a photographic photosensitive layer, a magnetic recording layer, or various other recording layers. There are various types depending on the purpose and use. For example, recording materials with a photographic layer include general photographic materials, microphotographic materials, radiation-sensitive materials, photographic materials for printing, photographic materials for scientific use, photographic paper, heat-developable materials, and many others. Examples include laser recording materials sensitive to laser beams, magnetic recording tapes with magnetic recording layers, magnetic recording films, and numerous other examples. As will be described later, the fundamental technical idea of the present invention is to provide a fine mat on the surface of an object, so a recording material is specifically specified as a useful object. Of course, you don't have to ask all the questions. In other words, providing a fine mat can be applied to the surface of any material,
Since the most effective example of the object to which the present invention is applied is a recording material, the invention is clarified by limiting the object f of the present invention to recording materials.

The support in the recording material of the present invention has a surface that is stable in storage, and in the case of a photosensitive material, it is preferably in the form of a sheet or a plate for convenience in handling. In the case of a magnetic recording material, it is in the form of a tape or a sheet, and a preferred form is selected depending on the practical use of the recording material or the equipment used. The support material may be paper; for example, paper coated with heat-melting plastic such as polyethylene, polypropylene, or polystyrene, aluminum, various aluminum alloys, metal plates such as zinc, iron, copper, etc.; Films of plastics such as cellulose acetate, cellulose butyrate, cellulose butyrate, propionic cellulose, cellulose triacetate, cellulose nitrate, polyethylene terephthalate, polypropylene, polycarbonate, polyvinyl acetal, etc.; metals such as those mentioned above are laminated or vapor-deposited. Includes coated paper or plastic film. The material of the support is also appropriately selected depending on the purpose and use of the recording material.

In addition, as the recording layer of a recording material, for example, as a photosensitive layer of a photographic light-sensitive material, there are many known types such as a silver halide-gelatin emulsion photosensitive layer, a diazo resin photosensitive layer, a photosensitive resin photosensitive layer, and others. It is used as a photosensitive layer of the photographic material of the present invention.

The same applies to laser recording materials and magnetic recording materials.
Regarding the other configurations, materials, manufacturing processes, and recording processes and uses of these recording materials, known techniques may be used, and detailed explanations here are not considered necessary.

The present invention is a method for matting the front and/or back sides of the recording material described above, and for this purpose, a coating liquid containing a solvent with a boiling point of 7300C or higher in which a resin is dissolved or dispersed is applied to the desired surface. The parts are electrostatically attached and then dried. Such a coating liquid is preferably one that adheres to the front or back surface of the recording material in a uniformly electrostatically dispersed state. Therefore, in the case of photographic light-sensitive materials, laser recording materials, etc., the resin of the coating liquid is a copolymer of acrylic ester and acrylic acid or methacrylic acid, as described in JP-A-17-311KJT. Copolymers of styrene, acrylic esters, acrylic acid or methacrylic acid; Copolymers of acrylic esters, styrene, acrylonitrile, etc. and acrylic acid or methacrylic acid, maleic acid, itaconic acid, etc.; Polyvinyl alcohol, polyvinyl acetate,
Vinyl polymers such as polyvinyl gyrolidone are selected as appropriate, and by a conventionally well-known method,
It is dissolved or dispersed in a coating solution containing a solvent with a boiling point of 13,000 or higher. Solvents with a boiling point of less than 13θ0C do not provide sufficient effects of the present invention.

In this case, if only a solvent with a boiling point of 13,000 or more is used, the subsequent drying will require a long time at high temperature, and sometimes it will have an adverse effect on the recording material.It is therefore preferable to use a low/medium boiling point solvent with a boiling point of 3θ0C or less, which is especially safe. It is more preferable to add water from the viewpoint of properties, influence on recording materials, solubility or dispersibility, etc.

When the coating solution is an aqueous solution containing water, the solvent with a boiling point of 130'C or higher is preferably a water-soluble solvent, and the amount of the solvent to be added is determined according to the amount in the coating solution! ~vO wt % is preferred. High boiling point solvent: 5% by weight
If the amount is less, the effect of the combined use of water will not be sufficiently exhibited, and on the other hand, if the amount is more than 0% by weight, the drying load will be large and post-drying will likely be insufficient.

Examples of bath agents that are soluble in water with a boiling point of 30°C or higher include ethylene glycol (boiling point: lψ7.Ij 0C), ethylene glycol monomethyl nitrate (boiling point: lψj, 70C), ethylene glycol (boiling point: lψj, 70C), Recol monoethyl ether (same as /J!, f'c) Ethylene glycol monoethyl ether acetate
(Same: Ijt, I 0C) Ethylene glycol monodityl ether (boiling point: /7/, 2°C) Ethylene glycol isoamyl ether (Same: 1I10
C') Methoxymethoxyethanol (same: /l, q, 50c) Ethylene glycol monoacetate (same: it2°C) Ethylene glycol diacetate (same: near 90.2 °C) Diethylene glycol (same: 21φ, 33°C ) Diethylene glycol monomethyl ether (1 Tsukasa:/
'i'! , Co'C) diethylene glycol monoethyl ether (diethylene glycol monoethyl ether (same = 20)
1. R'C) Diethylene glycol heptanoethyl ether acetate
(Same:, 2/7.≠0c) Diethylene glycol monobutyl ether (Same = 230.ψ0q) Diethylene glycol dimethyl ether (Boiling point: /A2
°C) diethylene glycol methyl ethyl ether
(Same: /4cJ-'C) Diethylene glycol diethyl ether (Same, igg, ≠'C) Diethylene glycol acetate (Same, 2j00C) Triethylene glycol d: 27g, J/'C) Triethylene glycol monomethyl ether
(Same: 2≠ri0c) Triethylene glycol monoethyl ether
(Same: 233, Ri'c) Tetraethylene glycol (Same: J27.joC) Propylene glycol (Same: lj1.2°C) Propylene glycol monoethyl ether (Same: 132
．． 2°C) l-butoxyethoxyzolonominol (boiling point: 2.2P, l'c) dipropylene glycol (boiling point: x3t, l0C) cifurohin glycol 7-methyl ether
(Same 2/De00C) Schiff's Rengelicol Monoethyl Ether
(Same: /ri7.za0c)), Ri fo pyrene glycol monomethyl ether (Same: 2≠3°
C) Trimethylene glycol (same = 27O~2//℃) Butanediol (same: 207.lI'c)/,! −
Ben/cundiol (same as 2≠λ, roc) Hexylene glycol (same as 2≠λ, roc) Glycerin (same as that: 2 ri o, o'c') Glycerin acetate (same as that: ljza'c) Examples include glycerin diacetate (boiling point: 2j - 4/'C).

As an example of a method for preparing an aqueous liquid, the above-mentioned copolymer can be prepared by emulsifying the raw material monomers in water using a surfactant and using a polymerization initiator such as potassium persulfate in the same manner as the usual latex synthesis method. Alternatively, a part of acrylic acid, methacrylic acid, →leic acid, itaconic acid, etc. may be converted into a sodium salt, potassium salt, or ammonium salt to form an aqueous copolymer solution. A coating solution can be prepared by adding a water-soluble solvent having a boiling point of 130 DEG C. or higher to these aqueous solutions.

These coating solutions may contain fillers such as other water-soluble substances, fine particle powders of inorganic substances, and powders of polymers, which do not affect the photosensitive layer or the attached droplets.

In addition, in the case of a mat provided on the back side of a magnetic recording tape, the aqueous resin may be a latex of a copolymer of vinylidene chloride and acrylic ester or acrylic acid, vinyl chloride and vinyl acetate, styrene, etc. There are copolymer latexes, styrene-citadiene copolymer latexes, water-soluble polymers of maleic anhydride and acrylic esters, and inorganic powder fillers such as carbon black and colloidal silica, as well as fatty acids and fatty acid esters. A coating liquid can be prepared by adding a water-soluble solvent with a boiling point of 1300 or more to an aqueous liquid containing emulsions such as oils and fats or salts as a lubricant.

The concentration of resin in the aqueous liquid is preferably j-3.
It is about 0% by weight.

The above-mentioned aqueous liquid is usually made into fine droplets in a process or device for statically depositing the droplets. Such processes or devices include conventionally practiced or known electrostatic air spray methods, electrostatic airless spray methods, rotary atomization electrostatic coating methods, and Tokkosho! There are methods such as the electrostatic coating method as described in J-217φθ, and devices using each method. Basically, all of them are made by turning the coating liquid into fine particles and electrostatically charging them to connect them to the electrode. Fine droplets of aqueous liquid are electrostatically attached to the surface by utilizing the electric field between the surface and the surface.

One suitable method for carrying out the present invention is rotary atomization electrostatic coating. This method has been explained in detail in many documents, and many improvements have been made since then. According to this type of device, io per minute
, ooo-to, 000 rotations Aqueous liquid is applied to the rear inner peripheral surface of the cup-shaped spray head, for example! ~/,000cc is continuously supplied at a rate of 1 minute, and the aqueous liquid in the spray head is formed into a thin film on the inner peripheral surface by the centrifugal force caused by rotation, and this thin film is flowed onto the cup-shaped surface along with the supply. From the tip of the spray head, the electrostatic action of the nuclear tip to which a voltage of -jθ to -hazo KV is applied together with the centrifugal force causes the atomization to be released, and atomization occurs between the rotating spray head and the surface of the recording material. The action of the formed high electric field causes atomized and charged fine droplets to fly and adhere to the surface of the recording material.

The most distinctive feature of the present invention is that, as described above, the coating solution contains a solvent with a boiling point of 1300 C or more, and the droplets are electrostatically attached. When a solvent with a boiling point of 1300C or higher is not included, the charged and atomized fine droplets dry while flying to the surface of the recording material, becoming thicker droplets than the initial concentration and forming very fine droplets. In some cases, it becomes a fine powder of dried resin. Therefore, when a droplet adheres to the surface of a recording material, it wets and spreads, making it easier to fall off because the contact area becomes smaller, and when it becomes a dry fine powder, the spherical fine powder is electrostatically attached. It becomes nothing more than a To prevent this phenomenon, a solvent with a boiling point of 300C or higher is added. By adding a high boiling point solvent, the solvent does not dry completely even when it is blown onto the recording material, making it easier to wet and spread over the surface of the recording material, thereby forming a strongly fixed mat. This high boiling point solvent can be reduced to a level that does not affect product performance through a drying process after matte formation.

Another effect of the present invention is that in the above-mentioned rotary atomization electrostatic coating method, the flow of the thin film coating liquid within the rotating cup-shaped spray head tends to deteriorate in some areas, and when continuous operation is performed for a long time, the resin However, by adding a high boiling point solvent, drying and precipitation can be suppressed and stable production can be carried out for a long time.

In the process of the present invention, the concentration of the resin and high boiling point solvent in the coating solution, the size of the atomized droplets, the surface temperature of the recording material,
The running speed of the recording material, the time from when droplets are attached to the surface until drying, etc. affect the form of the mat formed. By changing these various conditions, the height of the mat after being dried can be arbitrarily controlled.

As described above, the recording material to which fine droplets of the coating liquid containing a solvent with a boiling point of 300C or higher are attached is dried, and the solid portion of the droplets is firmly adhered to the surface and becomes matte. .

The added high-boiling solvent is then reduced to a level that does not adversely affect the performance of the product. Drying and its conditions are as follows:
Any technique conventionally known in the art may be used, such as blowing warm air onto the recording material, passing it through a high temperature, low humidity chamber, using an infrared heater, etc. to dry the recording material.

The dried mat is dotted on the surface of the recording material, and in the case of photographic light-sensitive materials, the coating amount is 0.3 (77 m or less, preferably θ, ljf/m2 or less, the F1 distribution is 1 to /θθθ
pieces/nt Hl 2, preferably t-t o 4
(It is in the range of about 57mm2, and the height of each matte particle is Q, ~20μ, size [diameter] ~7~θO)
It is preferably in a range of approximately μ.

When the coating amount is 0.3 f/nt2 or more, it becomes difficult to remove the high boiling point solvent by post-drying.

In addition, in cases other than photographic light-sensitive materials, the distribution amount is lθ~jθθ
particles/mm2, and the height of the matte particles is O0θ3~1. jμ,
The diameter of the matte particles is about 10 to 10θθμ.

Hereinafter, the present invention will be specifically explained based on Examples.

Example 1 ノ琲さ o-, 2≠nl 1) Both sides of the aluminum plate of t were grained using a water suspension and thoroughly washed with water.

This board was heated to 70°C in aqueous solution of sodium terpenophosphate (3%).
After soaking in water for 3 minutes, it was washed with water and dried.

This support is coated with polyhydroxyphenyl naphthoquinone-7, cocyazido, which is obtained by the condensation polymerization of acetone and pyrogallol as described in Japanese Patent Publication No. Sho φJ-21403. - Prepare a photosensitive solution by dissolving 2 parts by weight of sulfonic acid ester and 2 parts by weight of novolak type phenol formaldehyde resin in 20 parts by weight of 2-methoxyethyl acetate and 20 parts by weight of methyl ethyl ketone, and apply the photosensitive solution to each side of the support. The coating was sequentially coated and dried, and a matte layer was applied by spraying as described below to prepare a double-sided photosensitive lithographic printing plate. The printing plate created in this way is loo3mmxrθ
Samples A, B, and C were cut into pieces with a size of θmm.
, D.

The composition of the coating liquid for each of these samples is shown in Table 1.

These coating solutions were coated using an electrostatic coating device having a cup-shaped rotating atomizing head under the following conditions.

Amount of water-based paint delivered in grams per minute! The applied voltage to the electrostatic coating head was θ milliliter, the voltage was applied to the electrostatic coating head, and the atomization head rotation speed was 30,000 revolutions per minute.The fine droplets of the coating solution were dried. The time from application to the drying room was approximately 3 seconds for both samples.
B is tθ 0 (15 for 5 seconds in an atmosphere with humidity IO%, sample CXD is /, 2 (also 0 in the case of a sample of dry hot air at 170c)
．． oA9/m2, jθ~10O1 hard/mm20 distribution, height was about 2-6μ, and diameter was about 10-10μ.

When the sample prepared in the above manner was brought into contact with the transport roll, the transport roll was contaminated and the film original plate (!
! θtnmxtsomm) and vacuum-adhered using a vacuum adhesion printer, the vacuum adhesion time, the dirt on the film base plate after vacuum adhesion, and the state of resin precipitation on the bell were investigated.

The results are shown in Table 2.

In A, which uses a conventional coating liquid, the conveying roller and the original film are dirty, and the matte easily comes off, resulting in poor vacuum adhesion on the back side.

In addition, precipitation within the coating bell was suppressed, and defective mats were generated within one hour, requiring production to be stopped and the bell to be cleaned. On the other hand, when a solvent is added, isozorobyl alcohol has no effect at all, and ethylene glycol monomethyl ether (boiling point 12≠, ≠0C) has an effect, but it is found to be insufficient.

The sample plate according to the present invention could be operated continuously for a long time without causing resin precipitation on the bell or staining of the conveying roller or film original plate. Furthermore, it was confirmed that the vacuum adhesion time was also stable.

Example 2 The double-sided type photosensitive lithographic printing plate in the sample of Example 1 was changed to a single-sided type, and a similar test was conducted. It exhibited vacuum adhesion similar to the surface of the sample of Example 1, and no stains were observed on the conveyor roll or on the original film plate.

Example 3 One side of the double-sided photosensitive lithographic printing plate in the sample sample of Example 1 was heated at ≠, 000 revolutions per minute using a disk in place of the cup-shaped rotating atomizing head in the sample sample of Example 1. As a result of coating, good results similar to those of the sample of Example 1 were obtained.

Example 4 Styrene-butadiene copolymer latex "NIPOL"
-LX-2゜≠" (manufactured by Nippon Zeon ■), colloidal silica "Snowtex OL" (manufactured by Nichikagaku ■), and sodium stearate (first class reagent) as solid contents, respectively,
/ and λ heavy duty part, methoxymethoxyethanol (boiling point / z7゜z (l c > tt parts, remainder #) Ir7 parts by weight are prepared as water to make an aqueous dispersion of a synthetic resin,
In the same manner as in the above example, the material was coated on the back side of a VH8 type magnetic tape for long-term recording to form a mat. The shape of the mat was 10.1.0 μm in diameter, □ in height, 0.3 to 0.3 μm, and the distribution amount of the mat was 1 o-to pieces/mm 2 .

When this sample and a magnetic tape of the same type with a mat attached were run on a videotape recorder to examine the tape's ejection and running conditions, the sample of this example showed good results, but the tape of the comparative sample showed a slightly better result. The result was inferior. The adhesion of the mat was also good, and it did not fall off even after several running tests.

The present invention described in detail above is applicable to forming a mat by electrostatically depositing aqueous g in the form of fine droplets on the front or back surfaces of various recording materials and drying them. In other words, it improves the vacuum adhesion of various recording materials, prevents mutual adhesion and adhesion, prevents static electricity, imparts sticky properties, improves the running properties of tape-shaped recording materials in cassettes, and improves the running properties of magnetic films. Various purposes can be achieved, such as preventing pecking. And according to the present invention,
It is possible to uniformly distribute and provide fine mats on the recording material, and the mats attached to the recording material are extremely firmly attached and do not fall off easily.

Therefore, even in the case of photographic light-sensitive materials, the reproducibility of halftone dots is good without impairing the original photographic properties.

In addition, it is a method that allows the thickness of the mat to be adjusted appropriately according to the various intended uses as mentioned above, and it is also possible to perform matting more stably with simpler equipment than the conventional method. Manufacture is possible.

Claims (1)

[Claims] l) Fine droplets of a coating liquid in which resin is dissolved, dispersed, or dispersed are electrostatically attached to the front and/or back surface of the recording material.
The method of matting the front and/or back surfaces by drying, wherein the coating solution contains a solvent having a boiling point of 300C or higher. 2) The solvent! 2. The method for matting according to claim 1, wherein the amount of matt is equal to or more than 10% by weight. 3) The matting method according to claim 1, wherein the coating liquid is an aqueous liquid containing a water-soluble solvent having a boiling point of 300C or higher in an amount of 3-4AO by weight. 4L) The matting method according to claim 1, wherein the recording material is a photosensitive lithographic printing plate. j) The amount of mat applied is o, 3y/m2 or less, and the height is 0.
1-. 20μ, the diameter) is /-200μ, and the distribution amount is /-1000 pieces/mm2.