JP2681657B2 - Roll film for photography - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a roll film wound with light-shielding paper and attached with a sealing paper to prevent unrolling, and more specifically, when the film is loaded into a camera. The present invention relates to a roll film packaging material that prevents improper loading, transport failure in a camera, and winding looseness.

[Background of the Invention]

A so-called Brownie type roll film such as 120 size or 220 size uses a light shielding paper as shown in FIG. 1 in a light shielding form for preventing the film from being exposed to external light.
Conventionally, this light-shielding paper was formed of black paper containing carbon. However, with the recent increase in the sensitivity of the film, higher performance than ever before is required for the light-shielding property and emulsion resistance of the light-shielding paper. In addition, the 220 size that has emerged as a long type of Brownie film is one that is wound on a spool with light-shielding paper named leader and trailer joined to the leading and trailing ends of the film,
This is rolled up with film and shading paper 12
Compared to 0 size, higher light-shielding property is required for light-shielding paper.

For this reason, a method has been adopted in which a backing layer is provided on the back surface of the light-shielding paper to prevent pinholes, paper width dimension fluctuations, and the like.

As described above, it is necessary for the light-shielding paper to have a light-shielding property for a large purpose, and at the same time, the condition that it is excellent in handling is important.

That is, it is necessary that after the roll film is set on the camera, the winding torque is light, or the winding does not easily slip.

For that purpose, the shading paper needs to be flexible,
It has been said that thinning the light-shielding paper is the simplest and most effective method for imparting the flexibility. Also, due to the thinning of the light-shielding paper, the roll diameter of the roll film becomes smaller, and the tolerance range expands even in the unlikely event of loose winding or winding failure. The points increase.

[Problems to be solved by the invention]

FIG. 1 is a perspective view of the Brownie film after the interior thereof. A part of the narrow portion 7 and the taper portion 8 at the tip of the light-shielding paper is folded along a folding line 6 and wound, and a sealing paper 4 is stuck to prevent it from unraveling.

As shown in Fig. 2, this envelope has adhesive 5 on both ends.
Is coated. As this adhesive, a hot-melt type adhesive based on a thermoplastic resin is usually used. One end of the wrapping paper is heat-welded to the leading end portion of the light-shielding paper, and then the wrapping paper is wound around the belt once, and the other end. Is heat-welded to the surface of the envelope to prevent the light-shielding paper from unraveling.

When the shading paper 3 and a film (not shown) are wound around the spool 1 and the end portion 7 of the shading paper is in the state shown in FIG. 3, it is folded back as shown in FIG. When it is opened, a paper seal is attached and the state shown in FIG. 1 is obtained.

To load the film into the camera, tear off the sealed film envelope as shown in Fig. 1 and return it to the state shown in Fig. 4 and set the shaft of the film on the supply side of the camera.
As shown in FIGS. 5 and 6, the end of the light-shielding paper is inserted into the slit opening 11 formed in the body portion 10 of the empty spool 9 having the same size as the spool 1 of the shaft portion set on the winding side of the camera. The part 7 is inserted and folded, and the screens are sent one by one and photographed and wound.

It should be noted that this folding back is necessary for the user to easily cut the envelope and for making it difficult for the spool 9 that is inserted into the slit opening 11 to be removed during winding.

Now, the opening of this roll film varies depending on the user, but among them, in many cases, the band of the sealing paper shown by the width of b is broken and opened by the folded portion of the light-shielding paper shown in FIG. However, at this time, if the light-shielding paper is torn without tearing the envelope, various troubles may occur when the front end of the light-shielding paper is inserted into the spool 9 of the camera before shooting or is misaligned. Cause

Therefore, the light-shielding paper needs to have some strength when opening. However, in order to maintain this strength, it is naturally advantageous to make the light-shielding paper thick rather than thin. This is contrary to the thinning for imparting flexibility, and there is a problem as it is in order to improve the overall quality of the photographic roll film.

That is, even if the camera can be loaded in such a state, correct transport is not performed and a jam occurs on the way to cause winding failure, or bull or loose winding causes light leakage from the spool flange. As a result, defective light blocking occurs on the film. In order to solve this, it is necessary to consider not only the shading paper but also the physical properties of the envelope.

An object of the present invention is to solve such a problem.

[Means for solving the problem]

The purpose of this is to construct a photographic roll film, and the light-shielding paper that is wound around the spool together with the photographic film has a total thickness of 85 to 95 μm and a burst strength of 1.9 to 2.0 kg / cm ² ,
Further, the tensile strength in the width direction thereof is 2.9 to 3.2 kg / cm, and the total thickness of the sealing for preventing unrolling by sticking to the outer periphery of the light-shielding paper wound around the roll film is 60 to 70 μm, The tensile strength in the width direction is 1.8 to 2.0 kg / cm, and the width dimension is 15
Achieved by a photographic roll film characterized by being ~ 17 mm.

〔Example〕

 Hereinafter, the present invention will be described more specifically.

The base paper used for the light-shielding paper used in the present invention may be any of ordinary natural pulp paper, synthetic resin or synthetic paper using synthetic resin, but wood such as softwood pulp, hardwood pulp, softwood hardwood mixed pulp and the like. Natural pulp paper based on pulp is advantageously used. These papers may be formed by any of the generally known round net forming method and fourdrinier forming method. The base paper containing these natural pulps as a main component may contain various polymer compound additives. For example, as a dry paper strengthening agent, cationized starch,
Cationized polyacrylamide, anionized polyacrylamide, carboxy-modified polyvinyl alcohol, gelatin, etc., as a sizing agent, fatty acid salt, rosin derivative,
Dialkyl ketin dimer emulsion, petroleum resin emulsion, styrene-ammonium salt of maleic anhydride copolymer alkyl ester, etc. as pigment, clay, kaolin, calcium carbonate, barium sulfate, titanium oxide, etc.
Wet paper strength enhancers such as melamine resins, urea resins, epoxidized polyamide resins, fixing agents such as polyvalent metal salts such as aluminum sulfate and aluminum chloride, cation-modified polymers such as cationized starch, and caustic soda as pH adjusters. , Inorganic carbonate such as sodium carbonate, hydrochloric acid,
In addition to salt, mirabilite, etc., dyes, optical brighteners, latex, carbon black, etc. may be appropriately combined and contained.

A resin layer may be laminated in order to impart physical properties that cannot be obtained only with paper.

Further, as a thermoplastic resin for processing the back surface of the base paper (hereinafter sometimes simply referred to as resin), Japanese Patent Publication No. 51-49205,
JP-A-48-22020, 50-67644, 55-140835,
58-17434, 58-186744, 59-68238, 60
-35728 low density, medium density, high density, linear low density various polyolefins such as polyethylene and polypropylene, polyvinyl-based such as ethylene vinyl acetate, acrylic such as ethylene ethyl acrylate and ethylene methyl acrylate, Rubber type such as styrene-butadiene,
Examples include simple substances such as ionomers, graft polymer polyamides, polyesters such as polyethylene-terephthalate, blends of two or more kinds, and copolymers. The above resin may be provided as two or more layers.

When laminating these resins on the base paper, an anchor agent may be used in order to further improve the adhesiveness, and examples of the anchor agent include organic titanium-based, isocyanate-based, polyethyleneimine-based and polybutadiene-based.

Means for providing these resins on a paper support can be broadly classified into two methods.

One of the methods is a method in which a liquid in which a resin is dispersed or dissolved in an organic solvent, water, or the like is applied to paper and dried.

As a coating method, for example, a reverse whirl method, a blade method, an air knife method, a rod method, a curtain method, an extrusion method, gravure printing, or the like can be used, but the coating method is not limited thereto.

A suitable dry film thickness of the resin layer obtained by these methods is 1 to 20 μm.

As another method, there is a method in which a resin is melted by heat and provided on a paper support. The most common coating method is the extrusion method, but other coating methods may be used.

The dry thickness of the resin layer obtained by this method is 5 to
50 μm is suitable.

The most advantageous method in the present invention is the former method of applying a dispersion or solution. In this method, since it is not necessary to consider the softening point of the resin to be applied so much, the softening point is not limited and a wide range can be selected, and a resin having a high softening point can be applied. However, in the latter case of hot melt coating, a resin having a limited resin softening point and a relatively high softening point must be raised in melting temperature, and a special coating process is required. In consideration of the adhesiveness between paper and resin, the former method is generally superior to the latter method.

In addition, the effects disclosed in Japanese Utility Model Showa 62-186708 can be easily combined to provide a more comprehensive improvement.

Carbon black used in the resin layer, paper layer, or other layer in the present invention is a furnace, channel,
It may be manufactured by any of the thermal methods.

Also, as actual products, for example, carbon black # 5, # 20, # 33, # 40, # 44, # 45, # manufactured by Mitsubishi Kasei
52, # 900, # 1000, # 2200B, # 2350 #, # 2400B, MA
8, MA100, etc., but not limited thereto.

Characters and symbols necessary for the function are printed on the surface of the light-shielding paper, or printing is performed to enhance the commercial value, but the ink used for these printing is selected as harmless to the photosensitive material and is generally used It can be selected from among offset printing ink, gravure printing ink or UV ink.

Typical synthetic resins used for these inks are vinyl acetate based, nitrified cotton, polyester, polyamide urethane,
Polyacrylic, rosin-modified maleic acid, ethylene vinyl acetate,
Vinyl ether, urethane vinyl acetate, vinyl chloride vinyl acetate urethane resin, modified alkyd resin modified phenol resin, alkali-soluble resin (rosin modified maleic acid resin, styrene maleic acid resin, styrene acrylic acid resin, acrylic acid ester acrylic acid resin, methacrylic acid Ester acrylic acid resin), hydrosol type resin (styrene maleic acid resin, styrene acrylic acid resin, α-methylstyrene acrylic acid resin, acrylic acid ester acrylic acid resin, methacrylic acid ester acrylic acid resin), emulsion type resin (styrene resin, Styrene acrylic ester resin,
Acrylic ester copolymer resins, methacrylic ester copolymer resins), and polymers with acrylic unsaturated groups are commonly used as resins for UV inks, and typical examples are polyester / acrylic ester. , Polyester / urethane resin / acrylic acid ester, epoxy resin / acrylic acid ester, pentaerythritol triacrylate, trimethylolpropane triacrylate, hexanediol diacrylate, neopentyl glycol diacrylate, triethylene glycol diacrylate, hydroxyethyl methacrylate To be

A commonly known coloring agent is used in combination with these inks. As the colorant used, Japanese Patent Application No. 61-1894
Various pigments and azo pigments described in No. 25 (azo lake; carmine 6B, red 2B, insoluble azo; monoazo yellow (PY-1, -3), disazo yellow (PY-12, -13, -14,
-17, -83), pyrazolo orange (PO-B-34) vulcan orange (PO-16), condensed azo type; chromophthalello (PY-93,95) chromophthal red (PR-144, -16)
6), polycyclic pigment (phthalocyanine type; copper phthalocyanine blue (PB-15, -15-1, -15-3), copper phthalocyanine green (PG-7), oxysazine type; dioxazine violet (PV-23) , Isoindolinone type; isoindolinone yelo (PY-109, -110), slene type; perylene, perinone, flavantron, thioindigo, lake pigment (malachite green, rhodamine B, rhodamine G, Victoria blue B) or inorganic pigment (Oxides, titanium dioxide, red iron oxide, sulfates; precipitated barium sulfate, carbonates; precipitated calcium carbonate, silicates; hydrous silicates, anhydrous silicates, metal powders; aluminum powders, bronze powders, zinc dust , Carbon black, yellow lead, navy blue, etc. These applications may be added as a light-shielding substance to the above-mentioned resin layer paper layer, etc. Soluble dyes and dispersible dyes are also used, etc. Other various solvents, dispersants, wetting agents, defoamers, leveling agents, thickeners, stabilizers, cross-linking agents, waxes, etc. , Dryers and other additives are used.

A varnish may be applied to protect the surface gloss and the printed portion of the surface. The types of varnish used at this time include cellulosic resins such as acrylic resin and fibrin acetate, urethane resins, epoxy resins, polyester resins, ionomer resins, EEA resins, various polyethylene resins (low density, high density, linear low density polyethylene). Etc.), polypropylene resin, and other appropriate resins can be used. Also wax can be used.

Further, the base paper for the envelope used in the present invention is the same as that used for the light-shielding paper, and so is the printing ink and varnish.

As the thermoplastic adhesive used for the sealing paper, polyethylene, polypropylene, and other polyolefins, vinyl chloride, and other polyvinyls, ethylene ethyl acrylate, and other acrylics, polyesters, polyamides,
Examples thereof include, but are not limited to, rubber-based materials such as SBR, cellulose-based materials, ionomer resin-based materials alone, blends of two or more kinds, and EVA-based copolymers.

Next, an experimental example related to this experimental example is shown. Create a brownie size roll film using light-shielding paper and sealing paper under the above conditions, load this roll film into the camera and take a picture of the roll film. did.

However, the total thickness of the light-shielding paper in the above embodiment is a nominal value, and each has an allowable range of ± 3 μm.

〔The invention's effect〕

 The evaluation items are as follows.

Breaking of light-shielding paper: Visually judging whether the service section was broken. Leakage of light: Photographed using a camera of Mamiya RB67, and then exposed for 3 minutes with a light of 10,000 lux to check the state of developing fogging.

Bad winding: The firmness of the winding is confirmed by hand, and it is better to be tight.

Each sample in the examples of the present invention was 100 and the evaluation criteria were as follows.

○: 0/100 △: 1/100 to 5/100 ×: 5/100 or more The evaluation results are shown in the following table.

As described above, Samples 1, 2, and 3 of the examples of roll films produced under the conditions of the present invention all have good results. However, it can be seen that those that do not meet the conditions of the present invention have a defect in breakage, light leakage, or bad winding.

[Brief description of the drawings]

FIG. 1 is a perspective view of an installed Brownie film. Figure 2 is a top view of the envelope. FIG. 3 is a plan view of the Brownie film in the interior, leaving a slight edge of the light-shielding paper. FIG. 4 is a side view of FIG. FIG. 5 is a plan view of the spool for winding at the time of photographing. FIG. 6 is a side sectional view showing a state in which the light-shielding paper terminal is inserted into the slit of the take-up spool. 1,9 ...... Spool flange 3 ...... Light-shielding paper 4 ...... Encapsulation 5 ...... Thermoplastic resin adhesive 6 …… Folding line, 7 …… Narrow end part 8 …… Tapered part 10 …… Winding shaft, 11 ...... Slit mouth

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 60-152151 (JP, U) Real Kai Hei 1-90041 (JP, U) Real Kohei 6-45964 (JP, Y2) Real Kohei 2- 33237 (JP, Y2) Actual Kohei 4-49621 (JP, Y2)

Claims (1)

(57) [Claims] 1. A light-shielding paper comprising a photographic roll film and wound around a spool together with a photographic film, having a total thickness of 85 to 95 μm and a burst strength of 1.9 to 2.0 kg / cm ² ,
Furthermore, the tensile strength in the width direction is 2.9 to 3.2 kg / cm, and the total thickness of the sealing paper which is stuck on the outer periphery of the light-shielding paper wound around the roll film to prevent unrolling is 60 to 70 μm, The tensile strength in the width direction is 1.8 to 2.0 kg / cm, and the width dimension is 15
A roll film for photography, characterized in that it is ~ 17 mm.