JPH0561156A - Photographic film package - Google Patents

Abstract

PURPOSE:To enable smooth mounting of a film package on a film holder. CONSTITUTION:A light-shielding envelope 3 is formed by laminating paper sheets 7a, 7b on both surfaces of a polyethylene sheet 6, and further, a lubricant layer 8 is formed on the paper 7b. The light shielding envelope 3 has rigidity due to the polyethylene sheet 6. Since the lubricant layer 8 is formed on the inner surface of the envelope 3, a film unit can be smoothly mounted and dismounted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic film package in which a sheet-shaped photographic film is stored in a light-shielding envelope so that it can be freely taken in and out.

[0002]

2. Description of the Related Art Relatively large size (for example, 12.5
A photo film package in which a sheet-shaped photo film of 10 cm) is stored in a light-shielding envelope is Japanese Patent Application No. 2-41115.
Proposed in No. 4. The light-shielding envelope is formed with an opening through which the photographic film can be taken in and out, and since this opening is normally closed with a light-shielding clip, it is not exposed to external light.

This photographic film package is used by loading it in a film holder mounted behind the camera.
When loading, operate the lock lever of the film holder to set it to the unlocked position. Then, with the light-shielding clip at the top, the photo film package is inserted into the film holder, the lock lever is set to the lock position, and the light-shielding clip is locked. When the light-shielding envelope is pulled out in this state, the engagement between the light-shielding clip and the light-shielding envelope is released, and the photographic film is exposed through the opening so that a photograph can be taken. When the light-shielding envelope is pushed into the film holder in order to store the exposed photographic film in the light-shielding envelope in a light-tight manner after the photographing is finished, the opening is closed by the light-shielding clip and the inside becomes light-tight. After that, when the lock lever is set to the unlocked position and the light-shielding envelope is pulled out again, the photographic film package is taken out from the film holder.

[0004]

Since the above-mentioned photographic film package is disposable, the light-shielding envelope is made of carbon-mixed black paper having a thickness of 240 .mu.m to suppress the manufacturing cost. However, a light-shielding envelope composed only of paper cannot secure sufficient rigidity, and the light-shielding envelope may curl when left in a humid place for a long time. Therefore, there is a problem in that when the photographic film package is loaded into the film holder, the photographic film package cannot be inserted smoothly or that defective loading frequently occurs. SUMMARY OF THE INVENTION It is an object of the present invention to provide a photographic film package which can be smoothly loaded into a film holder.

[0005]

In order to achieve the above-mentioned object, the invention according to claim 1 uses a constituent material of a light-shielding envelope for accommodating a photographic film in a light-tight manner, with a rigidity between the colored paper and the colored paper. The laminated sheet was provided with the thermoplastic resin provided therebetween. In the invention of claim 2, a lubricant layer is formed on the inner surface of the light-shielding envelope. Hereinafter, the present invention will be described in more detail with reference to the drawings.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a photographic film package in which a photographic film unit is pulled out from a light-shielding envelope. The photographic film package 2 is composed of a light-shielding envelope 3 whose enlarged cross-sectional view is shown in FIG. 2 and a photographic film unit 4 housed therein. At the rear end of the light-shielding envelope 3, there is formed an opening 5 through which the photographic film unit 4 is taken in and out. In addition, the tip of the light-shielding envelope 3 is
Since it is grasped by a finger or the like when the sheet is pulled out, a reinforcing cardboard 9 is attached to this portion. A notch 9a is formed in the central portion of the cardboard 9 so that the upper surface and the lower surface of the light-shielding envelope 3 can be directly grasped when the whole is pulled out. The portion to which the cardboard 9 is attached projects to the outside from a film holder (not shown) when the photographic film package 2 is loaded.

In order to increase the rigidity and prevent curling, the constituent material of the light-shielding envelope 3 is a pair of polyolefin-based thermoplastic resin sheets, for example, polyethylene sheet 6, which are mixed with carbon black on both sides as shown in FIG. Paper 7
It has a three-layer structure in which a and 7b are joined. Paper 7a, 7b
Is bonded by extrusion lamination of polyethylene. In such a three-layer laminated sheet, curl can be further reduced as compared with a paper in which resin is coated on one surface. As the papers 7a and 7b, those having substantially the same expansion / contraction rate with respect to temperature changes and humidity changes are used so that the curl balance is not disturbed. Since the paper 7b becomes the inside of the light-shielding envelope 3 and comes into contact with the photographic film unit 4, 1 is placed on the lower side of the paper 7b (the side in contact with the photographic film).
g / m ² ~15g / m ² of lubricant layer 8 wax was applied
Are formed. The lubricant layer 8 makes it possible to smoothly pull out and push in the light-shielding envelope 3 and prevent the photographic film unit 4 from being scratched. Although the light-shielding envelope 3 is manufactured by extrusion lamination in this embodiment, it may be manufactured by dry lamination or wet lamination. Although polyethylene resin is used as the thermoplastic resin, various polyolefin resins (homopolymerization resin, copolymerization resin, and mixed resin of two or more kinds) may be used for production.

Even with the above construction, if the basis weight of the papers 7a and 7b is 60 g / m ² or less, the rigidity of the light-shielding envelope 3 cannot be ensured, so that the photographic film package 2 can be put into or taken out of the film holder. , Bends. Further, when the basis weight is 120 g / m ² or more, it is difficult to put in and take out the film holder. Thus paper 7a, the basis weight of 7b is preferably ^{60g / m 2 ~120g / m 2} , It should be noted that the paper 7a in this embodiment, 7b basis weight is used as a 90 g / m ^2. The papers 7a and 7b have a carbon black concentration of 2 wt% to 15 wt% (1.2 g / m ^{2 to} 18 g).
/ M ² ), light reflection is suppressed on the surface of the light-shielding envelope 3, and the light-shielding property of the light-shielding envelope 3 is secured. In addition,
When not only carbon black but also a black dye is mixed with the papers 7a and 7b, the light blocking effect can be further enhanced.
For example, a shading paper containing carbon black and a cationic dye is proposed in Japanese Patent Application No. 2-221160.

The light-shielding envelope 3 must prevent the reflection of light on the surface, and it is essential to color the papers 7a and 7b. However, regarding the light-shielding property, a combination of the papers 7a and 7b and the polyethylene sheet 6 is used. May be taken into consideration. For example, carbon black may be embedded in the polyethylene sheet 6 to secure the light shielding property. In this case, it is preferable to keep the carbon black concentration within the range of 0.5 wt% to 10 wt%. By doing so, even if the photographic film package 2 is left under the illumination of 10,000 lux for 10 minutes, the inside of the light-shielding envelope 3 can be kept light-tight.

The polyethylene sheet 6 has a thickness of 10 μm.
If it is less than m, the polyethylene film will not be formed well during lamination, and the adhesive force with the papers 7a and 7b will be insufficient. The thickness of the polyethylene sheet 6 is 70 μm
When it is above, the workability at the time of laminating becomes poor and the cost is increased. Therefore, the thickness of the polyethylene sheet 7 is preferably set within the range of 10 μm to 70 μm. The basis weight of the polyethylene sheet 7 having a thickness of 10 μm to 70 μm is 10 g / m ^{2 to} 70 g.
/ M ² . The polyethylene sheet 7 having such a thickness can sufficiently secure moisture resistance, and the light-shielding envelope 3
It is possible to prevent moisture from entering the inside of the. Also,
If the paper 7a, 7b is made of waterproof paper or the paper 7a, 7b is made waterproof, the light-shielding envelope 3 can be made more moisture-proof. Furthermore, by impregnating the papers 7a and 7b with a resin, it is possible to further increase the rigidity of the light-shielding envelope 3.

As shown in FIG. 2, a light-shielding clip 10 for closing the opening 5 of the light-shielding envelope 3 is provided at the rear end of the photographic film unit 4, and the first carrier sheet 11 is caulked to the light-shielding clip 10. It is fixed. The first carrier sheet 11 is releasably joined to the lower surface of a photographic film 12 in sheet form via hot melt. A second carrier sheet 13 is attached to the leading end of the photographic film 12.
Is detachably bonded to the upper surface of the via hot melt. The second carrier sheet 13 has a leading end cut into a trapezoidal shape for facilitating the entrance and exit of the photographic film unit 4 with respect to the light-shielding envelope 3, and a step with the photographic film 12 is formed on the upper surface of the rear end. Step correction sheet 14 for correction
Are joined.

Slits 15 and 16 having different width sizes are formed in the trapezoidal portion, and the slits 15 are formed when the tip of the photographic film package 2 is folded back after photographing.
The second carrier sheet 13 is easily bent, and the slit 16 makes the upper surface and the lower surface of the light-shielding envelope 3 directly contact with each other when the light-shielding envelope 3 is pinched by a finger, and the light-shielding envelope 3 and the photographic film unit 4 are displaced from each other. I'm trying to pull it out together. For the purpose of this folding position, it is preferable that the rear end of the thick paper 9 and the slit 15 are aligned.

The operation of the photographic film package 2 thus constructed will be described. As shown in FIG. 3, in the photographic film package 2, the rear end of the light-shielding envelope 3 is fitted into the light-shielding clip 10 and the opening 5 is closed. The photo film package 2 is loaded into the film holder (see, for example, USP4821054) with the clip 10 first. At the time of loading, the film holder is set to the unlocked state. After this insertion, the light-shielding clip 10 is set in the locked state and is locked to the film holder.

When the thick paper 9 is lightly gripped and pulled in this state, the light-shielding envelope 3 is disengaged from the light-shielding clip 10 and only the light-shielding envelope 3 moves to the position shown in FIG. Since the inside of the light-shielding envelope 3 is coated with wax, even if the photographic film unit 4 comes into contact with the photographic film 1 during the movement, the photographic film 1
The 2 can be moved smoothly without being scratched.
Then, the photographic film 12 is exposed from the light-shielding envelope 3,
You can shoot.

When the light-shielding envelope 3 is pushed into the film holder after photographing, the photographic film unit 4 is stored in the light-shielding envelope 3 as shown in FIG. At this time, since the light-shielding envelope 3 is given rigidity by the polyethylene sheet 7 and the central portion of the opening 5 does not swell, its operability is good. When the light-shielding envelope 3 is further pushed in, the rear end portion of the light-shielding envelope 3 is smoothly fitted into the light-shielding clip 10 and the opening 5 is closed.

Next, when the film holder is set in the unlocked state and the notch 9a is strongly pinched, the upper and lower surfaces of the light-shielding envelope 3 come into direct contact with each other via the slit 16. When the light-shielding envelope 3 is pulled out in this state, the photographic film unit 4 is not displaced and the light-shielding envelope 3 is not displaced.
Along with that, it is pulled out from the film holder. After this,
When the light-shielding envelope 3 is bent at the end of the thick paper 9 and fixed with tape, the photo-film unit 4 is prevented from moving inside the light-shielding envelope 3 while the photo-film package 2 is being handled, and the light-shielding clip 10 is provided. It can be prevented from coming off from 3.

Hereinafter, a light-shielding envelope 3 made of the three-layer laminated sheet of the present invention and a light-shielding envelope made of a single piece of paper 7a will be described under condition 1 (temperature 23 ° C., humidity 65%) and condition 2 (temperature 4).
Table 1 shows the experimental results in which the film holders were left for several hours at a temperature of 0 ° C. and a humidity of 80%) and then loaded into a film holder, and the effects of operability and humidity were investigated.

[0018]

[Table 1] Operability: The insertion can be done quickly and smoothly with one hand. △: Can be inserted by operating slowly. ×: It was difficult to insert, and loading failure occurred frequently. Effect on photographic film (○) ・ ・ ・ ・ No problem (△) ・ ・ ・ ・ Slight change (×) ・ ・ ・ ・ Problem From these experimental results, the light-shielding envelope 3 of the present invention was compared with the comparative example. It can be seen that the light-shielding envelope has improved rigidity, operability, and moisture resistance.

The basis weights of the papers 7a and 7b are set to 60, respectively.
g / m ² , the basis weight of the polyethylene sheet 6 is 60 g /
m ² , a light-shielding envelope composed of a laminated sheet having a total thickness of 200 μm, the basis weights of the papers 7 a and 7 b are 120 g / m ² , and the basis weight of the polyethylene sheet 6 is 20 g.
/ M ² , and a light-shielding envelope composed of a laminated sheet having a total thickness of 280 μm was prototyped, left for a few hours in the above-mentioned conditions 1 and 2 and then loaded in a film holder. An experiment was conducted to examine the operability, and the operability was good regardless of which light-shielding envelope was used.

Although the light-shielding envelope 3 is composed of a three-layer laminated sheet in the above embodiment, the laminated sheet is made of paper 7a, laminate adhesive layer 31a, polyethylene terephthalate film 32, laminate adhesive layer 31b, paper as shown in FIG. 7
It may have a five-layer structure of b. The lubricant layer 8 is formed on the lower side of the paper 7b as in the above-described embodiment.

[0021]

As described in detail above, according to the first aspect of the present invention, a light-shielding envelope for storing a photographic film in a light-tight manner is provided.
Since it is composed of a laminated sheet with a thermoplastic resin interposed between the colored paper and the colored paper, the rigidity of the light-shielding envelope can be improved and curling can be prevented, so that the film holder can be smoothly loaded into the film holder. Can be done. Further, according to the second aspect of the present invention, since the lubricant layer is formed on the inner surface of the light-shielding envelope, the photographic film unit can be smoothly taken in and out, and the photographic film can be prevented from being damaged.

[Brief description of drawings]

FIG. 1 is a perspective view of a photographic film package showing a state in which a photographic film unit is pulled out from a light-shielding envelope.

FIG. 2 is an enlarged cross-sectional view showing a laminated sheet forming a light-shielding envelope.

FIG. 3 is a plan view of a photographic film package accommodating a photographic film unit.

FIG. 4 is an enlarged cross-sectional view showing a laminated sheet forming another light-shielding envelope.

[Explanation of symbols]

 2 Photo film package 3 Light-shielding envelope 4 Photo film unit 5 Opening 6 Polyethylene sheet 7a, 7b Paper 8 Lubricant layer 10 Light-shielding clip 12 Photo film

Claims (2)

[Claims] 1. A photographic film package comprising a photographic film unit having a sheet-shaped photographic film and a light-shielding clip, and a light-shielding envelope having an insertion opening closed by the light-shielding clip and storing the photographic film in a light-tight manner. The photographic film package, wherein the light-shielding envelope is composed of a laminated sheet in which a thermoplastic resin for imparting rigidity is interposed between colored paper. 2. The photographic film package according to claim 1, wherein a lubricant layer is formed on the inner surface of the light-shielding envelope.