JPS6050597B2 - Curved surface printing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for printing on non-planar surfaces such as curved surfaces and irregularly shaped surfaces.

A liquid tank that stores liquid, such as water, and a liquid on the liquid surface in this liquid tank,
A curved surface printing device is known that includes a printing pattern support sheet feeding device that feeds a printing pattern support sheet, which has a pattern to be printed on the surface of a thin film that is soluble in the liquid, so as to float it (Japanese Patent Application Laid-Open No. (See Publication No. 51-21914).

In this type of printing device, the printing pattern support sheet is
When it comes into contact with the liquid surface, the soluble thin film is partially dissolved in the liquid to the extent necessary for transfer, and the pattern to be printed floats on the liquid surface together with the partially dissolved thin film. When the printed surface of the printed article is immersed in the press-down liquid, the pattern is adhered to the printed surface by the liquid pressure. Therefore, when the article is pulled out of the liquid and the thin film is washed away with the liquid, the transfer printing of the pattern is completed. This type of printing device is advantageous in that it can print any pattern even if the surface to be printed is a non-flat surface such as a curved surface or an irregularly shaped surface, and can be applied to surfaces such as plastic wall clock cases, TV cabinets, radio cabinets, etc. suitable for printing.

However, in this type of known curved surface printing device, the soluble thin film comes in contact with the liquid for a predetermined period of time and is partially dissolved in the liquid to the extent necessary for transfer, and the pattern is supported by the semi-dissolved thin film and rises above the liquid surface. When the printed surface of the article is lowered and immersed in the liquid against the half-dissolved part of the thin film of the sheet floating in the liquid, the pattern is drawn into the liquid, and the thin film of the sheet connected to it is dissolved to the extent necessary for transfer. The parts that are not covered are also stretched and wrinkles occur, which tends to cause the pattern to become disordered or to have blank areas in the pattern.

If such a situation occurs, the pattern will not be the desired one when the part of the thin film that is not dissolved to the extent necessary for transfer changes to the part that is dissolved to the extent necessary for transfer, and therefore the product with the desired pattern will not be produced. This means that transfer printing will not be possible. In view of the above points, the present invention provides a sheet lifting member that separates the portion of the printed pattern support sheet where the thin film is dissolved to the extent necessary for transfer from the portion where the thin film is not dissolved to the extent necessary for transfer. There are some attempts to solve the above-mentioned problems.

An embodiment of the present invention will be described below with reference to the drawings.

The curved surface printing apparatus of the present invention is comprised of a printed pattern support sheet feeding device A shown in FIG. 1, and a pattern transfer device B to an article shown in FIG.

The printed pattern support sheet feeding device A has a frame 1, and the printed pattern support sheet S is mounted on the frame 1.
A bearing 2 is provided to detachably and rotatably support the roll R.

The printed pattern support sheet S is made of, for example, a thin film of water-soluble polyvinyl alcohol with a desired pattern printed in advance on one side.

In this case, the pattern printed on the thin film may be printed in a single color, but is preferably printed in multiple colors. The roll R is formed so that the printed surface of the sheet S is exposed to the outside, and the sheet S is pulled out from this roll R via guide rolls 3 and 4.

A solvent coating device 5 is provided next to the guide roll 4, and the sheet S is passed through the solvent coating device 5. The solvent coating device includes a plate cylinder 7 driven by a motor M via a chain 6, an impression cylinder 8 that is in contact with the top of the plate cylinder 7, and a plate cylinder 7 that applies a solvent to the outer peripheral surface of the plate cylinder 7. A liquid pan 9 that stores a solvent for dipping the lower part of 7, and a doctor blade 1
It is composed of 0. As the plate cylinder 7 rotates, the solvent in the liquid pan 9 is leveled by the doctor blade 10 and applied to the outer peripheral surface of the plate cylinder 7 in a uniform thickness, and is applied to the pattern printing surface of the print pattern support sheet S. . As a result, the pigments and resin that make up the printing pattern applied to the surface of the sheet S are partially dissolved and activated by the solvent to the extent that they do not melt and flow out, and become sticky as they were immediately after printing. It becomes something with sexuality. Note that the plate cylinder 7 may be used simply to apply a solvent, but it can also be used to further apply a gravure coat of another color to the preprinted printing pattern on the sheet S and to activate it.

Further, as the solvent coating device 5, any coating device such as a roll coater can be used. The sheet S having the printed pattern activated by applying the solvent as described above is further sent forward via the reversing roll 11 and the guide roll 12.

After passing the reversing roll 11, the printed pattern of the sheet S is located on the upper surface of the sheet. The sheet S is then fed further by the rotation of the suction rolls 13 and 14.

The suction roll 13 is driven by the motor M via chains 15 and 16, and the suction roll 1
4 is driven by a suction roll 13 via a chain 17. The suction rolls 13 and 14 have a large number of suction roll holes on their outer peripheries, and the vibes 13a and 1
It is connected to a vacuum pump through 4a, and feeds the sheet S while applying suction to the sheet S through the suction hole. From the suction roll 14, the sheet S is further conveyed along a downwardly inclined delivery plate 18, and enters a pattern transfer device B, which is an essential part of the present invention. Note that only one suction roll may be provided. As shown in FIG. 2, the pattern transfer device B includes a water tank 20. As shown in FIG.

This water tank 20 is formed long in the feeding direction of the sheet S, and stores water w (FIG. 3) inside. As shown in FIG. 3, a water flow generating device 21 is provided at the end of the water tank 20 closest to the printed pattern support sheet feeding device A. This water flow generating device 21 has an opening 22 connected to the discharge side of a pump (not shown) that pumps up water flowing out from an overflow part (not shown) provided at the other end of the water tank 20. The water is sent upward while being converted, and the water is sent out as a rectified stream through the slit 24 provided in the width direction of the water tank 20. Therefore, a water flow always occurs on the surface of the water W in the water tank 20 in the direction of the arrow X. As shown in FIG. 2, the printed pattern support sheet S descending while being guided by the delivery plate 18 is sent onto the surface of the water w in the water tank 20, and floats on the water surface while being washed away by the water current. It will be done.

As the sheet S is carried away by the water stream, the water-soluble thin film of polyvinyl alcohol or the like that constitutes the sheet S gradually dissolves in the water, swells, and becomes partially dissolved, and is supported by this partially dissolved thin film. In this state, the pattern will float on the water surface. This state is obtained when the sheet S reaches the position indicated by S1 in FIG. Therefore, the article E, which has a non-flat surface such as a curved surface or an irregular surface, is directed downward into the water as shown by the arrow Y toward the printed pattern floating on the water surface at the position shown as S1. When pressed down, the pattern attached to the surface of the article E at the moment of contact with the water surface is pressed against the surface of the article by water pressure acting on the article when it enters the water, and the adhesive force of the activated pattern causes the pattern to adhere to the surface of the article E. is adhesively transferred to. Therefore, the transfer is completed when the article E is lifted out of the water and washed to remove the thin film. When the article is pushed down towards the sheet S at position S1, the part of the sheet where the water-soluble film is insufficiently soluble in the water is pushed downstream in conjunction with the pattern floating on the water surface being pushed into the water. It is pulled toward the side, causing disturbance to the sheet floating on the water surface on the upstream side.

This disturbance of the sheet is undesirable because it disturbs the pattern. In the present invention, in order to avoid such inconvenience, the following means are provided.

That is, a pair of support members 30, 31, 31 are provided at the upstream end and downstream end of the water tank 20, respectively, and a sprocket wheel 3 is provided at the upper and lower ends of each support member 30, 31.
2, 33 and 34, 35 are provided, respectively. Then, on each side of the water tank 20, the sprocket wheels 3
An endless chain 37 is stretched across 2, 34, 35, and 33. at least one of the sprocket wheels
One is connected to a motor as a driving sprocket wheel, and a chain 37 is fed as shown by arrow Z. On the other hand, as shown in FIG. 4, a printed pattern support sheet lifting member 40 is connected between the two chains 37, 37 moving in parallel at a constant interval in the direction of movement of the chains.

In the illustrated embodiment, the lifting member 40 consists of a U-shaped bar. That is, this bar is composed of a horizontal bar 40a extending perpendicularly to the water flow direction X and a vertical bar 40b perpendicular to the horizontal bar 40a, and each of the vertical bars 40b is connected to the chain 37 by a connecting member. In this embodiment, the connecting member includes a pin 41 connected to the chain 37, a pin 42 connected to the vertical bar 40b, and a bar 43 connecting these pins 41 and 42. Incidentally, since the lifting action is performed by the horizontal bar 40a as described later, the vertical bar 40b does not necessarily need to be provided. In the intermediate portion of the water tank 20, the chain 37 is guided by idler sprocket wheels 45, 46 and moves almost horizontally along the inside of both side walls l of the water tank, as shown in FIG.

In this case, the height at which the chain 37 moves is such that the lifting member 40, which is supported by the chain and moves in the direction of the water flow, is
Set it so that it sinks slightly below the surface. This is to prevent the sheet S floating on the water surface from being disturbed by the movement of the lifting member 40. On the other hand, in the middle of the horizontal movement path of the chain 37 between the sprocket wheels 45 and 46, a pair of opposing lifting cams 50 are provided along the inside of both side walls of the water tank.

This lifting cam 50 is located slightly upstream of a position S, where the water-soluble thin film of the sheet S melts to the extent necessary for transfer, and when the chain 37 passes through that position, it lifts it somewhat upward. It has a curved surface that allows it to move (Figure 3). Therefore, when the lifting member 40 reaches the position of the cam 50,
As shown in FIG. 3, the sheet S is lifted slightly above the water surface, and as a result, the sheet S
will be lifted slightly above the water surface. After passing the area of the cam 50, the lifting member 40 descends again and sinks below the water surface. As described above, when the sheet S is slightly lifted, the sheet S has self-shape retention because its water-soluble thin film has not yet dissolved to the extent necessary for transfer. It is not disturbed by lifting.

In this way, by immersing the article E in water for transfer at the location S1 where the water-soluble thin film has been dissolved to the extent necessary for transfer, an adverse effect is exerted on the sheet S on the upstream side. Even if a part of the sheet S is lifted to the water surface by the lifting member 40, the influence of immersion of the article is cut off at the position of the lifting member 40, and as a result, the upstream It doesn't extend to the side.

Note that the lifting member 40 is moved at a speed that does not cause wrinkles etc. on the sheet S on the water surface (the feeding speed of the sheet S and the sheet S
The sheet is fed by a chain 37 at a speed that takes into account the speed at which the sheet spreads due to swelling), and is normally submerged under the water surface so that it does not disturb the sheet above the water surface. In the embodiments described above, water is stored in the tank 20, but any liquid other than water may be used.

In this case, the thin film of the sheet S is made of a material soluble in the liquid. As described above with respect to the embodiments, in the present invention, the areas where the thin film of the printing pattern support sheet has dissolved to the extent necessary for transfer printing are separated from the areas where the thin film has not dissolved to the extent necessary for transfer printing. By doing so, it is possible to easily and reliably prevent the effect of the pattern transfer operation on the area where the thin film has been dissolved to the necessary degree from affecting the area where the thin film has not been dissolved to the necessary degree.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a printed pattern support sheet feeding device of a curved surface printing device according to an embodiment of the present invention, FIG. 2 is a perspective view showing a pattern transfer device to an article, and FIG. 3 is a pattern transfer device. FIG. 4 is an enlarged longitudinal sectional view showing the main parts of the sheet lifting member. A... Print pattern support sheet feeding device, B...
Pattern transfer device, S...print pattern support sheet,
S1... Sheet portion where the thin film has been dissolved to the extent necessary for transfer, R... Roll of sheet S, M... Motor, w.
...Liquid (water), 5...Solvent coating device, 7...Print cylinder, 8...Impression cylinder, 9...Liquid pan, 10...Doctor plate, 13, 14...Suction roll, 21・
...Liquid (water) flow generator, 20...Liquid (water) tank, 37
... Chain, 40... Woot lifting member, 40a.
...Horizontal bar of seat lifting member, 50...lifting cam.

Claims (1)

[Scope of Claims] 1. A printing pattern support sheet comprising a liquid tank for storing a liquid, and a pattern to be printed on a curved surface on the surface of a thin film soluble in the liquid on the liquid level in the liquid tank. In the curved surface printing apparatus, the thin film of the printed pattern supporting sheet floating on the liquid surface is dissolved in the liquid tank to the extent necessary for transfer. A sheet lifting member capable of lifting the sheet above the liquid surface is provided in the area between the part and the part where the thin film is not dissolved to the extent necessary for transfer, and by lifting the sheet lifting member, the thin film is removed. A curved surface printing device characterized in that the disturbance of the sheet caused by the lowering of the printed article to the part where the thin film has been dissolved to the extent necessary for transfer is prevented from being transmitted to the part where the thin film has not been dissolved to the extent necessary for transfer. . 2. A device for generating a liquid flow in the liquid tank is provided, a device is provided for moving the sheet lifting member submerged in the liquid below the printed pattern support sheet that is flown by the liquid flow, and a device is provided for moving the sheet lifting member submerged in the liquid. A cam that acts on the sheet lifting member to lift it is disposed in an area between a portion of the support sheet where the thin film is dissolved to an extent necessary for transfer and a portion where the thin film is not dissolved to an extent necessary for transfer. A curved surface printing apparatus according to claim 1. 3. A curved surface printing apparatus according to claim 2, wherein an endless running member is provided that runs along both side walls of the liquid tank in the direction of liquid flow in the liquid tank, and the sheet lifting member is attached to the running member. .