JPH0563783B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a silver halide photographic material. More specifically, the present invention relates to a silver halide photographic material having a support produced by electron beam irradiation and particularly suitable as photographic paper. Prior Art and its Problems Baryta-coated paper (high-quality paper without a coating layer) is used as a support for conventional photographic paper. For this reason, the back side of conventional photographic paper includes your name,
Records such as dates were written in with a pencil and could be easily erased with an eraser. On the other hand, in recent years, in order to speed up photographic processing, paper base materials coated on both sides with polyolefin resins such as polyethylene have been used as supports. Since there is a resin coating layer on the back side of such a support, writing with a pencil is impossible. Although it is possible to write with water-soluble ink from a fountain pen, the letters become unclear and are easily erased by friction with fingertips. Furthermore, although it is possible to write with oil-based ink such as a ballpoint pen or marker, it cannot be erased or corrected. Therefore, in the case of a support having a polyolefin resin coating layer, in the same way as baryta coated paper,
There is a great demand for being able to write with a pencil. For this reason, several proposals have been made to impart pencil writability to the polyolefin resin coating layer. One of them is a composition coating containing powders such as silicon oxide and aluminum hydroxide in a binder such as gelatin, casein, and polyvinyl acetate.
This is a method of forming on the surface of a polyolefin resin coating layer. However, in this case, it is difficult to write well unless the writing pressure is increased, and when writing with a hard pencil, there is an inconvenience that if the writing pressure is high, a dent will be created in the writing area. In addition, in production, the process of coating and drying is increased, making the process complicated. On the other hand, JP-A-55-43528 discloses a technique in which fine powder of an inorganic substance having a Mohs hardness of 3 to 7 is contained in a polyolefin resin coating layer. However, in such cases, it is necessary to add a large amount of inorganic fine powder to improve the writability. At this time, stains occur at the die exit end of the polyolefin resin melt extruder, and streaks appear on the surface of the coating layer. occurs, resulting in extremely poor surface quality. Further, when the thickness of the coating layer is increased, the effect will not be produced unless the particle size of the powder is increased and the amount added is increased, so it is preferable to make the coating layer as thin as possible from the viewpoint of production efficiency. However, in order to form a thin coating layer, it is necessary to raise the melting temperature of the polyolefin resin to around 320 to 360℃, and at this time, part of the resin decomposes, causing pinholes and yellowing in the coating layer. This may cause distortion, deterioration of flatness, or have an adverse effect on the photographic emulsion. Furthermore, if the amount of fine powder added to improve writing properties is increased, the abrasion resistance and printing durability of the coating layer will deteriorate. The disadvantage is that a large amount of powder falls off. As described above, a support having a polyolefin resin coating layer that has practically sufficient writability has not been realized. On the other hand, as a support instead of a support having a polyolefin resin coating layer, a composition curable by electron beam is used as a support (paper) base, especially for the purpose of improving the sharpness of photographic images, water resistance, etc. JP-A No. 57-27257 and JP-A No. 57-57 have a coating layer coated on a material and cured by irradiating it with electron beams.
It has been proposed in No. 49946, etc. Since such a support is coated at room temperature, a large amount of white pigment can be contained in the coating layer on the emulsion layer side in order to improve sharpness.
Its dispersion is also easy and is advantageous in practice. However, no consideration has yet been given to the writability of the back surface of this support, and improvements are desired. OBJECTS OF THE INVENTION The first object of the present invention is to provide a support that allows writing on the back side even with a hard pencil, does not cause dents, and allows written characters and symbols to be clearly identified even with low writing pressure. An object of the present invention is to provide a silver halide photographic light-sensitive material using the present invention. The second purpose is to be able to easily erase characters written with a pencil on the back side with an eraser, which has excellent erasability, and also has excellent abrasion resistance so that powder, etc. does not fall off from the surface even when erased strongly with an eraser. An object of the present invention is to provide a silver halide photographic light-sensitive material using a support having a back layer. The third objective is to achieve these objectives with a support that has a back layer hardened by electron beams, thereby creating a support that can be cured at room temperature, has no yellowing, pinholes, decomposition, etc., and has excellent flatness. An object of the present invention is to provide a silver halide photographic light-sensitive material having a silver halide structure. A fourth object is to provide a silver halide photographic light-sensitive material using a support that has excellent adhesion between the back layer and the support base material and also has good flexibility. These objects are achieved by the invention described below. That is, in the present invention, on one side of a support base material, a compound that can be cured by electron beam, 30 to 300 parts by weight of hard fine powder with a Mohs hardness of 4 or more per 100 parts by weight of this compound, and 2 molecules in the molecule. A support having a back layer formed by setting a composition containing a coupling agent having different reactive groups as described above and curing with an electron beam, and a silver halide emulsion layer on the opposite side of the back layer of the support. This is a silver halide photographic light-sensitive material, which is characterized in that it supports a silver halide photographic material. Specific Configuration of the Invention The specific configuration of the present invention will be described in detail below. The electron beam curable compound used in the present invention has two or more unsaturated double bonds in its molecular chain, which can be cured by polymerization or crosslinking by generating radicals etc. by electron beam irradiation. Preferably, it is a compound containing Therefore, photographic supports having acrylic double bonds such as acrylic acid, methacrylic acid or their esters, allylic double bonds such as diallyl phthalate, unsaturated bonds such as maleic acid and maleic acid derivatives, etc. Any of the monomers, oligomers, and polymers that can be cured by electron beams and that are known for personal use or in various technical fields may be used. The molecular weight of the compound curable by electron beam is preferably 20,000 or less, particularly 500 to 20,000, particularly preferably about 1,000 to 20,000. Typical specific examples of compounds that can be cured by electron beams are listed below.

【table】

[Table] Two or more of these electron beam curable compounds can be used in combination. Furthermore, for the purpose of improving flexibility and adhesion of the support base material, thermoplastic resins represented by the following may be mixed and used. (1) Cellulose derivatives Nitrocellulose, cellulose acetate butyrate, ethyl cellulose, butyl cellulose, etc. (2) Polyvinyl alcohol resins Polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, etc. (3) Polybutadiene and butadiene copolymers Polybutadiene, acrylonitrile butadiene copolymer Polymers, styrene-butadiene copolymers, etc. (4) Vinyl chloride copolymers Vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinyl acetate-maleic acid copolymers, etc. (5) Polyurethane resins (6) Unsaturated, Saturated Polyester Resin (7) Polyamide Resin, etc. These thermoplastic resins may or may not have an acrylic modified double bond introduced therein. These thermoplastic resins are 80/20 to 40/60% by weight based on the total amount of the electron beam curable compound.
It is preferable to set the mixing ratio to . The hard fine powder in the present invention has a Mohs hardness of 4
That's all. It is also transparent or white. Among these hard fine powders, inorganic ones include fine quartz powder, fine glass powder, calcined alumina,
Examples include fused alumina (corundum) and garnet. Among these, quartz fine powder and glass fine powder are preferable because they protrude into the hardened back layer and improve writing properties. Note that if the Mohs hardness is less than 4, the writing ability of the pencil is insufficient. In addition, the average particle size of the hard fine powder is 0.5 to 30 μm,
Particularly preferred is 2 to 20 μm. If the average particle size is larger than 30 μm, the surface will feel rough when writing, and even if the writing appears dark, the pencil lead will have a large loss rate and the paper will easily get dirty. On the other hand, if the average particle diameter is less than 0.5 μm, writing with a pencil is poor. Note that hard organic fine powder can also be applied. Typical examples include methyl methacrylate resin, phenol resin, benzoguanamine formaldehyde resin, and polystyrene resin. In 100 parts by weight of a compound curable by electron beam,
The amount of hard fine powder is preferably 30 to 300 parts by weight, particularly preferably 40 to 250 parts by weight. If it is less than 30 parts by weight, the pencil retouchability is insufficient,
If it is more than 300 parts by weight, the coating layer becomes brittle and its adhesion to the support base material also decreases. Moreover, a good coated surface cannot be obtained. It is preferable that the composition made of such constituent materials further contains a coupling agent. The coupling agent used is a compound that has two or more different reactive groups in its molecule, and one of these reactive groups is one that chemically reacts with the hard fine powder (methoxy group, ethoxy group, silanol group, etc.).
The other is a reactive group (vinyl group, epoxy group, methacrylic group, amino group, etc.) that chemically bonds with a compound that can be cured by electron beams. Such a coupling agent has the function of acting as a bridge between the electron beam curable compound and the hard fine powder through chemical bonds. In this case, it is particularly preferable that the coupling agent suitably used in the present invention has an unsaturated double bond that is hardened by electron beam irradiation, as well as an alkoxy group that exhibits a coupling effect. A radical polymerization reaction occurs between this double bond and a radical generated from an unsaturated double bond of a compound that can be cured by an electron beam, thereby forming a crosslinked structure and curing the compound. Such coupling agents strongly bond, on the one hand, with hard fine powders and, on the other hand, with compounds curable by electron beams. For this reason, coupling agents with such unsaturated double bonds can effectively reinforce the interface of hard fine powders, improve wear resistance, and even when written characters are rubbed many times with an eraser, The effect is that the hard fine powder does not fall off. In addition, the hard fine powder can be effectively reinforced at the interface, the filling properties are improved, and the surface smoothness is further improved. As mentioned above, the coupling agent does not necessarily have to have a C═C unsaturated double bond, but in the case of a coupling agent that does not have a double bond in the molecule, it may chemically bond with the hard fine powder. Although it has reactive groups (methoxy group, ethoxy group, silanol group, etc.), it cannot be said that the bond between the hard fine powder and the binder made of the hardened compound is sufficient. That is, it does not form a strong chemical bond with the hardened binder, but only has good compatibility with the binder, and does not form a strong bond with the binder. Therefore, a strong bond between the hard fine powder and the binder does not occur, and although the above-mentioned effects are observed, they are not sufficient compared to those having double bonds. In this case, the coupling agent is preferably a silane coupling agent or a titanium coupling agent, which is added so as to coat the surface of the hard fine powder. That is, the coupling agent chemically bonds with the hydroxyl groups of the hard fine powder and the hydroxyl groups in the metal oxide layer partially covering the surface thereof. In other words, the silane coupling agent has a group that forms a silanol group and/or a silanol group, so in the form of a silanol group, it can absorb the hydroxyl groups of the hard fine powder and the metal oxide that partially coats the surface. It reacts with hydroxyl groups etc. on the surface of the object and forms a chemical bond with the hard fine powder. In addition, titanium coupling agents strongly react with the hydroxyl groups in the hard fine powder and the hydroxyl groups on the metal oxide surface that partially covers the surface, and form titanium atoms.

[Formula] or the bond with -OR is broken to form an ether bond or an ester bond. Specific examples of coupling agents of the present invention that are particularly suitably used are listed below. Silane coupling agent with unsaturated double bond in the molecule (1) CH ₂ = CHSi (OC ₂ H ₅ ) ₃ (2) CH ₂ = CHSi (OC ₂ H ₄ OCH ₃ ) ₃ (3) CH ₂ = CCH ₃ CO ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ (4) CH ₂ = CHCO ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ (5) CH ₂ = CCH ₃ CO ₂ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃ (6) CH ₂ = CHCO ₂ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃ (7) CH ₂ = CCH ₃ CO ₂ CH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ (8) CH ₂ = CHCO ₂ CH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ (9) CH ₂ = CCH ₃ CO ₂ CH ₂ CH ₂ CH ₂ Si
(OCH ₂ CH ₃ ) ₃ (10) CH ₂ = CCH ₃ CO ₂ CH ₂ CH ₂ CH ₂ CH ₂ Si
(OCH ₃ ) ₃ (11) CH ₂ = CHCO ₂ CH ₂ CH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ (12) CH ₂ = CHCO ₂ CH ₂ CH ₂ CH ₂ CH ₂ Si
(OCH ₂ CH ₃ ) ₃ (13) CH ₂ = CHCH ₂ NHCH ₂ CH ₂ CH ₃ Si(OCH ₃ ) ₃ (14) CH ₂ =
CHCH ₂ NHCH ₂ CH ₂ NHCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) Titanium coupling agent with double bonds in ₃ molecules The following methods can be used to incorporate such a coupling agent into the coating layer. That is, in the first method, a hard fine powder and the coupling agent dissolved in a solvent are simultaneously added to the above-mentioned one type or a mixture of two or more of the above-mentioned compounds curable by an electron beam, and then dispersed and mixed. rear,
This is a method in which it is applied onto a support base material and then cured. In the second method, the coupling agent is dissolved in a suitable solvent, the hard fine powder is immersed in this solution, the surface is treated in advance, and then one or a mixture of two or more types of electron beams are applied. In this method, the composition is dispersed and mixed in a compound that can be cured by a method of preparing a composition liquid, and then coated on a support base material and cured. The third method involves dissolving the above-mentioned compound or a mixture of two or more of the compounds that can be cured by electron beams in an appropriate organic solvent, surface-treating the surface with a coupling agent in advance, and dispersing and mixing the dried hard fine powder. After that, it is applied onto a support base material and cured. Furthermore, a fourth method involves dispersing and mixing a coupling agent with a hard fine powder in an organic solvent before adding a compound that can be cured by electron beams, and then adding a compound that can be cured by electron beams. In this method, after preparing a composition liquid, it is applied onto a support base material and cured. Among these, a method using hard fine powder that has been previously treated with a coupling agent and dried is preferred. In addition, in these, when an organic solvent is used, the viscosity of a composition liquid becomes low, the filling property of hard fine powder improves, and the surface smoothness of a back layer improves further. The amount of these coupling agents used is preferably in the range of 0.1 to 20% by weight based on the hard fine powder. If it is less than 0.1% by weight, the desired effect will not be obtained;
If it exceeds 20% by weight, it may bleed out over time. In this case, the coupling agent is more preferably
It is preferable to use it in a range of 0.5 to 10% by weight. The composition for coating the back layer in the present invention comprises these electron beam curable compounds and hard fine powder, and a solvent may be added to this composition. In this case, especially when using organic solvents,
Since the viscosity of the coating composition becomes lower, the filling properties of the hard fine powder are further improved, and the surface smoothness is further improved. The solvent to be used is not particularly limited and is appropriately selected in consideration of the solubility, compatibility, etc. of the compound curable by the electron beam used, the coupling agent, etc. Solvents that can be suitably used in preparing the composition include methanol, ethanol, isopropanol,
Alcohols such as butanol Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone Esters of methyl acetate, ethyl acetate, butyl acetate, and ethyl butyrate Glycol ethers such as ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, dioxane, etc. Benzene, toluene, xylene, etc. Examples include aromatic hydrocarbons, aliphatic hydrocarbons such as hexane and heptane, and mixtures thereof. As the support base material used in the present invention, in addition to commercially available medium-quality paper and high-quality paper, paper base materials made of natural pulp, synthetic pulp, or a mixture thereof can be used. Alternatively, a film may be used in which an inorganic white pigment is dispersed in a polyester or polyolefin base, if necessary. In addition, it is preferable that the basis weight of the paper base material is 60 to 250 g/m ² , more preferably 80 to 190 g/m ² ,
Its surface may be smooth or rough. The composition for coating in the present invention is prepared as follows. That is, the above-mentioned components are charged into a kneading machine either all at the same time or one after the other. Various kneaders are used for kneading and dispersing the coating composition. Usable kneading machines include two-roll mill,
There are three roll mills, pepple mills, ball mills, sand grinders, high speed stone mills, high speed impact mills, kneaders, homogenizers, etc. Moreover, as a coating method, methods such as air doctor coating, blade coating, squeeze coating, air knife coating, reverse roll coating, and cast coating are used. The coating thickness is preferably 1 to 100 μm, more preferably 5 to 50 μm. If it is less than 1 μm, the intended purpose cannot be achieved, and
If the thickness exceeds 100 μm, the cost will increase. Such a coating composition is applied to the back side of the support base material, and then subjected to electron beam irradiation to be cured to form a back layer. In this case, the emulsion layer-carrying surface of the support base opposite to the back layer contains a compound curable by electron beams as described above, an inorganic white pigment, a thermoplastic resin as necessary, and various coupling agents. It is preferable to provide an undercoat layer by applying a composition containing agents, solvents, etc., and curing the composition with an electron beam. As the inorganic white pigment used in this case, any of titanium oxide (anatase type, rutile type), barium sulfate, calcium carbonate, aluminum oxide, magnesium oxide, etc. can be used. Further, the surface of titanium oxide may be partially coated with a hydrous metal oxide, such as a hydrous alumina oxide or a hydrous ferrite oxide. The amount of the inorganic white pigment is preferably in the range of 30 to 300 parts by weight based on 100 parts by weight of the electron beam curable compound. If it is less than 30 parts by weight, the sharpness will not be sufficient, and if the amount is less than 30 parts by weight,
If the amount exceeds 1 part by weight, the adhesion and surface smoothness will not be sufficient. In this case, 30 to 200 parts by weight is more preferable. In addition, the average particle diameter of the pigment is preferably 0.1 to 10 μm. Further, the quantitative ratio of the compound curable by electron beam and the thermoplastic resin added as necessary is the same as described above. Furthermore, when using coupling agents and solvents,
The quantitative ratio may be the same as above, and the type of solvent may also be the same as above, but the coupling agent may not necessarily have a double bond. Further, the coating method and coating thickness may be the same as those for the back layer. To apply the composition for coating the back layer and undercoat layer onto the support base material, use a two-stage coater head to simultaneously coat the emulsion-coated side and the opposite side, and immediately heat and dry. After removing part or all of the solvent, the coating layer may be cured by electron beam irradiation, and then wound onto a roll. Alternatively, the coating layer may be cured by electron beam irradiation immediately after coating, followed by heat drying to remove the solvent in the cured layer, and then wound onto a roll. If you do not have a two-stage coater head,
First, it is applied to the emulsion-coated side, dried and cured in the same manner as above, then wound up on a roll, and then coated on the opposite side, dried and cured in the same manner as above.
A method of curing and winding up into a roll may also be used. When applying and winding according to each of the above methods, after the composition liquid is prepared, it is stable without being affected by changes in temperature and humidity or the concentration of the material used, and it does not cause aggregation or gel even when applied. There is no problem, and stable coating operation can be performed for a long time. In addition, when the support base material and the layer first applied and cured on the support base material are overlapped, or when the layer applied and cured on the opposite side is overlapped,
Since blocking due to bleed-out of the coupling agent etc. does not occur, there is no reduction in coating operability or deterioration of the surface condition of the coating layer. Even when the composition liquid according to the present invention contains a large amount of hard fine powder, even when applied after long-term storage,
There is no aggregation or gel formation, the coating operation is good, and there is no blocking during winding. The back layer and undercoat layer of the present invention can be smoothed to give a mirror finish, and can also be molded if necessary. To achieve a mirror finish, the surface to be treated can be brought into contact with a mirror roll, and an electron beam is irradiated from the back side of the roll to harden it, thereby giving the surface a mirror finish. Also,
A method may be used in which the surface is partially cured by performing preliminary irradiation in advance, and then brought into contact with a mirror-finished roll, peeled off, and then subjected to secondary irradiation to be completely cured. Examples of mirror-finished rolls include chlormetsuki rolls and stainless steel rolls. Also, when applying molding, surface polishing can be applied to rolls such as stainless steel rolls and chrome plated rolls, which can be used instead of mirror-finished rolls.
By vapor deposition method, etching method, plating method, etc.
A roll with a desired pattern such as a silk texture or a fine grain surface can be used. Mirror finishing and molding treatment may be performed after applying the composition and removing part or all of the organic solvent, or may be performed after molding and removing the organic solvent. The drying temperature for the back layer and undercoat layer is approximately 50-120℃.
℃, preferably 70 to 100℃, particularly preferably
The temperature is 80 to 90°C, and the drying time is about 10 seconds to 10 minutes, preferably about 20 seconds to 5 minutes. The electron beam accelerator used may be any one of an electrocurtain system, a Huang graph type scanning system, a double scanning system, and the like. In addition, in terms of electron beam characteristics, in terms of penetrating power,
It is preferable to use an electron beam accelerator of 100 to 750 KV, preferably 150 to 300 KV, and the absorbed dose to be 0.5 to 20 Mrad. In addition, when irradiating with an electron beam, N ₂ , He, CO ₂
It is desirable to irradiate in an inert gas atmosphere such as A lubricant, an abrasive, an antistatic agent, etc. may be added to the coating composition liquid of the present invention, if necessary. In addition, in order to improve the adhesion with the photosensitive silver halide emulsion layer, the undercoat layer may be subjected to surface treatment such as corona treatment, or another undercoat layer may be applied to the surface of the undercoat layer. Good too. Preferably, the layer structure of the silver halide emulsion layer and silver halide photographic material disposed on such an undercoat layer may be any known one. Specific Effects of the Invention According to the present invention, even a hard pencil can be used to write on the back side without creating any dents, and furthermore, written characters and symbols can be clearly identified even with low writing pressure. In addition, characters written in pencil on the back side can be easily erased with an eraser, and the back layer has excellent erasability and has excellent abrasion resistance so that powder, etc. does not fall off from the surface even when erased strongly with an eraser. It will be done. These effects are realized in a support having a back layer cured by electron beams, so
It can be cured at room temperature, does not cause yellowing, pinholes, decomposition, etc., and provides a support with excellent flatness. Furthermore, a support can be obtained that has excellent adhesion between the back layer and the support base material, has good flexibility, and has very little stress cracking or stress cracking. Furthermore, the stability of the coating composition is also good. The present inventors conducted various experiments to confirm the effects of the present invention. An example is shown below. Experimental example (1) Preparation of sample No. 1 Fine quartz powder with Mohs hardness of 7 and average particle size of 5 μm
50 parts by weight Urethane acrylate oligomer [Exemplary compound (5), n=10] 50 parts by weight (CH ₂ =CHCOOCH ₂ ) ₃ C-C ₂ H ₅ 20 parts by weight Polyurethane resin (manufactured by BFGoodrich)
Estane 5702) 30 parts by weight methyl ethyl ketone/toluene (1:1 mixture)
A composition consisting of 50 parts by weight was prepared and mixed and dispersed in a ball mill for 32 hours. After that, this composition was coated on one side of a high-quality paper weighing 150 g/m ² to a thickness of 30 μm using a curtain coater, and then the solvent of this coating was removed by drying (100° C. for 1 minute). Using an electron beam accelerator, this coating was irradiated with an electron beam at a dose of 150 KV and 5 Mrad in a nitrogen gas atmosphere, and then the cured coating layer was once rolled up. Let this sample be No. 1. (2) Preparation of Samples No. 2 to 4 Perform the same operation as in Sample No. 1 using 50 parts by weight of quartz fine powder with average particle diameters of 10 μm, 20 μm, and 50 μm, respectively, instead of the quartz fine powder in Sample No. 1. After coating, drying and curing, it was rolled up. Let the respective samples be No. 2, No. 3, and No. 4. (3) Preparation of sample No. 5 Fine glass powder with Mohs hardness of 4 and average particle size of 10 μm
After washing and drying 100g using acetone,
The exemplified coupling agent (7) was added to 500 ml of a methanol solution in which 5 g was dissolved, mixed and stirred for 2 hours, and then left to stand for about 6 hours. The solvent was removed under reduced pressure, and the fine glass powder was heat treated at 130°C for 10 minutes. Next, the surface-treated glass fine powder 50 parts by weight of acrylic modified butadiene (TEA-1000 manufactured by Nippon Soda Co., Ltd. 70 parts by weight _CH2 =CH-COO-( _CH2 ) _6- OOC-CH= _CH2
20 parts by weight trimethylolpropane triacrylate
10 parts by weight methyl ethyl ketone/toluene (1:1 mixture)
After preparing a composition consisting of 50 parts by weight and mixing and dispersing it in a ball mill for 48 hours, this composition was coated on one side of high-quality paper weighing 180 g/m ² using a curtain coater to coat a 30 μm thick paper.
It was coated with a thickness of . Next, after drying (100°C for 1 minute) the solvent on this coating was removed, the coating was irradiated with an electron beam at a dose of 150KV 7Mrad in a nitrogen gas atmosphere using an electron beam accelerator, and then cured. The coated layer was then rolled up. This sample is designated as No.5. (4) Preparation of Samples No. 6 to 8 Compositions in which the surface-treated fine glass powder of Sample No. 5 was added to 100 parts by weight, 200 parts by weight, and 400 parts by weight, respectively, were prepared as No. 5. Cover with the same operation,
The samples prepared by drying and curing are designated as Sample Nos. 6, 7, and 8, respectively. (5) Preparation of sample No. 9 Fine quartz powder with Mohs hardness of 7 and average particle size of 10 μm
40 parts by weight Acrylic modified butadiene (TEA-1000 manufactured by Nippon Soda Co., Ltd. 70 parts by weight CH ₂ = CH-COO- (CH ₂ ) ₆ -OOC-CH=CH ₂
20 parts by weight trimethylolpropane triacrylate
10 parts by weight Exemplary compound (15) titanium coupling agent 4 parts by weight Methyl ethyl ketone/toluene (1:1 mixture)
A composition consisting of 50 parts by weight was prepared, mixed and dispersed in a ball mill for 72 hours, and then the same operation as No. 1 was performed to prepare a sample, which was designated as No. 9. (6) Preparation of samples No. 10 and 11 Instead of the fine quartz powder of sample No. 1, calcium carbonate with a Mohs hardness of 3 and an average particle size of 1 μm and talc with a Mohs hardness of 1 to 1.5 and an average particle size of 5 μm were used.
A sample was prepared by coating, drying, and curing in the same manner. Sample Nos. 10 and 11, respectively. (7) Preparation of Samples No. 12 and 13 In Sample No. 1, the same amount of glass fine powder with average particle diameters of 10 μm and 50 μm without surface treatment was used, and No.
Samples prepared in the same manner as in 1 are referred to as sample Nos. 12 and 13, respectively. Each sample obtained was evaluated according to the method described below. (1) Surface finish Smoothness was visually evaluated. (2) Writability Measured using a writing tester manufactured by Toyo Seiki. Place the prepared sample on the sample stand, and insert a 100 mm
A load of g was applied, and then the pencil lead was moved over a 10 cm sample, and the density of the drawn line was measured. Excellent writability = 15 or higher Good writability = 10 to 15 (Practically usable) Poor writability = 10 or less (Practically unusable) (3) Powder falling when erasing with an eraser Erase the written characters with an eraser, This was repeated 10 times and the degree of powder falling off was observed. 〇 = No powder coming off at all △ = Some powder coming off × = Powder coming off easily after 1 to 2 coats (4) Adhesion of paint film A 25 mm x 25 mm square cellophane tape ( Nichiban) was applied and the cellophane tape was removed instantly, and the condition of the coating film was evaluated using the following four-level criteria. ◎ No abnormalities 〇 Partial peeling △ More than half peeling × Completely peeling (5) Flexibility (bending test) A bending tester was used. The condition of the coating film was evaluated using the following four-grade criteria, with the coated surface facing outward, bending radius of curvature of 2 mm, and bending angle of 180°. ◎ No abnormalities after 10 repetitions 〇 Partial cracks after 5 repetitions △ Full cracks after 5 times × Whole cracks after 1 time (6) Erasability of pencil-written characters Visually inspected as 〇, △, × A three-level evaluation was conducted. These results are shown in Table-1.

[Table] From the results shown in Table 1, the effects of the present invention are clear.

Claims (1)

[Claims] 1. On one side of the support base material, a compound that can be cured by an electron beam and 30 to 300 parts per 100 parts by weight of this compound.
A support having a back layer formed by applying a composition containing part by weight of a hard fine powder with a Mohs hardness of 4 or more and a coupling agent having two or more different reactive groups in the molecule, and curing with an electron beam. 1. A silver halide photographic light-sensitive material comprising a support and a silver halide emulsion layer supported on the side opposite to the back layer of the support.