JP7042051B2 - Developing equipment and developing method - Google Patents

Description

The present invention relates to a developing apparatus and a developing method.

Conventionally, there has been known a technique for manufacturing a printing plate by forming irregularities on a photosensitive resin layer provided on the surface of an original plate. For example, by irradiating the original plate with ultraviolet light through an image mask and exposing the photosensitive resin layer in a predetermined pattern, an exposed portion and an unexposed portion are formed on the photosensitive resin layer (exposure step), and the original plate is formed. By rubbing the surface of the original plate with a brush while supplying the developing liquid to the surface, the resin in the unexposed area is scraped off to form a relief (development process), and the rinse liquid is supplied to the surface of the original plate on which the relief is formed to generate debris. A technique for producing a water-developable flexible printing plate through a step group of removing (rinsing step) has been proposed (see, for example, Patent Documents 1 and 2).

Since such a water-developable flexographic printing plate has a high affinity between debris and the plate surface, a large amount of new developer (developer containing no resin) is used to remove debris from the plate surface, and a large amount is required. Rinsing with water and both are often performed. After rinsing, visually check whether debris has adhered to the plate surface, and if debris remains, redevelopment for a short time or remove debris with tweezers. ing.

Japanese Unexamined Patent Publication No. 2011-64796 JP-A-2015-125398A

By the way, in recent years, a metal bar is attached to the tip of a large (long) original plate, and the bar is transported in a predetermined direction by a transport means such as a chain and arranged at predetermined intervals along the transport direction. A so-called "in-line type" development process has been proposed in which a development process and a rinsing process are continuously performed by rubbing the surface of the original plate with a plurality of brushes. In such an "in-line type" development process, since the development area where the development process is performed and the rinse area where the rinsing process is performed are adjacent to each other, debris remaining on the surface of the original plate that has passed through the development area is present. It is brought into the rinse area, and debris may easily remain on the plate surface even after rinsing.

In this regard, the technique described in Patent Document 1 is a technique of gradually separating the brush from the plate surface while rotating the brush at the end of the developing process. Since it is necessary to rotate the brush around a rotation axis extending in a direction orthogonal to the transport direction and to move the brush along the direction orthogonal to the rotation axis, there is a possibility that a large-scale modification of the device may be required. Further, the technique described in Patent Document 2 is to brush the plate surface with a brush having a hair diameter of 25 to 180 μm while supplying specific rinse water containing a surfactant having a pH of 9 or higher to the plate surface in the rinsing step. However, since it is necessary to prepare a brush having a specific rinse water and a specific hair diameter, there is a possibility that a considerable amount of labor and cost will be required to implement the brush.

The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the amount of debris brought into the rinsing region without making major modifications to the apparatus when performing in-line development processing. And.

In order to achieve the above object, the developing apparatus according to the present invention is an apparatus for developing an original plate having a photosensitive resin layer on the surface, and a predetermined plate in which an exposed portion and an unexposed portion are formed on the photosensitive resin layer. The unexposed part is removed by rubbing the surface of the original plate, which is arranged in the developing area and is arranged in the developing area. The unexposed part removing part, the rinsing liquid supply part that removes debris from the surface of the original plate by supplying the rinsing liquid in the rinsing area adjacent to the downstream side of the developing area to the original plate conveyed by the transporting part. The developing liquid supply unit includes a first developing liquid supply unit that supplies a developing liquid containing a used developing liquid to the upstream region of the developing region, and a filtered product obtained by filtering the used developing liquid. It has a second developing liquid supply unit that supplies the developing liquid to the downstream region of the developing region.

Further, the developing method according to the present invention is a method for developing an original plate having a photosensitive resin layer on its surface, and transports an original plate in which an exposed portion and an unexposed portion are formed on the photosensitive resin layer in a predetermined direction. While supplying the developing solution to the original plate in the developing region, the developing step of removing the unexposed portion by rubbing the surface of the original plate with the unexposed portion removing means, and the developing step of transporting the original plate through the developing step in the above direction, Including a rinsing step of removing debris from the surface of the original plate by supplying the rinse liquid to the original plate in the rinse region adjacent to the downstream side of the developing region, and in the developing step, the developing liquid containing the used developing liquid is used. While supplying to the upstream region of the developing region, the filtered developing liquid obtained by filtering the used developing liquid by a filtering means is supplied to the downstream region of the developing region.

By adopting such a configuration and method, development can be performed using the filtered developer in the latter half of the development process (that is, on the downstream side of the development region), so that the amount of debris brought into the rinse region is significantly reduced. Can be made to. Therefore, it is possible to reduce the amount of the rinsing solution (new developer or water) used in the rinsing process, and it is also possible to reduce the amount of debris adhering to the original plate that has undergone the rinsing process. There is no need to make major modifications to the brush drive mechanism. Further, in the first half of the developing process (that is, on the upstream side of the developing area), the used developing solution is reused for development, so that the new developing solution can be saved and the trouble of filtering the entire amount of the developing solution can be saved. Can be omitted. Here, as the "downstream region" to which the filtered developer is supplied, a region including the downstream end of the developing region and occupying 10 to 20% of the entire developing region can be adopted.

In the developing apparatus according to the present invention, the rinsing liquid supply unit includes a new liquid supply unit that supplies a new developer containing no used developer to the upstream region of the rinsing region as a rinsing liquid, and a rinsing unit that uses water as a rinsing liquid. It can have a water supply unit that supplies the area downstream of the area. Further, in the developing method according to the present invention, the rinsing step includes a new liquid rinsing step in which a new developing solution containing no used developer is supplied to the upstream region of the rinsing region as a rinsing liquid, and a rinsing step in which water is used as a rinsing liquid. It can include a water rinsing step, which supplies the area downstream of the area.

When such a structure and method are adopted, debris can be efficiently removed from the original plate because rinsing can be performed in two steps using a new developer and water.

In the developing apparatus according to the present invention, the water supply unit can supply the used water stored in the water supply source as a rinsing liquid. Further, in the developing method according to the present invention, the used water stored in the water supply source can be supplied as a rinsing liquid in the water rinsing step.

When such a configuration and method are adopted, since the development is performed using the filtered developer in the latter half of the developing process, the amount of debris adhering to the original plate at the time of water rinsing is small, so that the amount of debris mixed in water is small. The stored water can be used more continuously.

According to the present invention, when performing an in-line development process, it is possible to reduce the amount of debris brought into the rinse region without making major modifications to the apparatus.

It is a block diagram for demonstrating the whole structure of the developing apparatus which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following embodiments are merely suitable application examples, and the scope of application of the present invention is not limited thereto.

First, the configuration of the developing apparatus 1 according to the embodiment of the present invention will be described. The developing device 1 according to the present embodiment is a device called an "in-line type", which is a device for developing a plate P having a photosensitive resin layer on its surface. In the developing apparatus 1 according to the present embodiment, the developing process of the original plate is performed using water containing a surfactant as a developing solution. Such development processing is referred to as "water development".

The original plate P is formed by forming a photosensitive resin layer on the surface of a support (not shown), and has a sheet shape as a whole. As the photosensitive resin, for example, acrylic resin, polyester, nylon, polyvinyl alcohol and the like can be used. A part of the surface of the original plate P is irradiated with ultraviolet rays prior to the development process by the developing apparatus 1. In the part exposed to ultraviolet rays (that is, the exposed part), a chemical change occurs in which the photosensitive resin is cured. On the other hand, in the unexposed portion, the photosensitive resin is not cured. In the developing process of the developing apparatus 1, the uncured photosensitive resin is removed, and irregularities having a predetermined pattern are formed on the surface of the original plate P.

As shown in FIG. 1, the developing apparatus 1 includes a transport unit 2, a discharge unit 3, and a brush unit 4.

The transport unit 2 is configured to transport the original plate P, and has an original plate mounting unit 22 on the upper surface thereof. The original plate P is placed on the original plate placing portion 22 so that the exposed surface faces upward. A guide plate 24 is fixed to one end of the original plate P. The guide plate 24 is a metal member and has a flat shape. The transport unit 2 has a guide chain (not shown). The guide chain is arranged along the original plate mounting portion 22, and the end portion of the guide plate 24 is locked to the guide chain. When a motor (not shown) is driven, the guide chain rotates to move the guide plate 24 along the original plate mounting portion 22. As a result, the original plate P is conveyed in the direction indicated by the arrow A.

The discharge unit 3 is configured to discharge the developer and water, and has a plurality of discharge pipes 31, 32, 33, 34. The discharge pipes 31, 32, 33, and 34 are all arranged above the original plate mounting portion 22 and have a pipe shape.

The discharge pipes 31 and 32 supply the developer to the original plate P transported by the transport unit 2 in the development region (first development region 11 and second development region 12 described later), and the development in the present invention. Functions as a liquid supply unit. The discharge tube 31 supplies the developer containing the used developer to the upstream region (the first developer region 11 described later) of the developer region, and functions as the first developer supply unit in the present invention. The discharge tube 32 supplies the filtered developer obtained by filtering the used developer to the downstream region (second development region 12 described later) of the development region, and the second development in the present invention. Functions as a liquid supply unit.

The discharge pipes 33 and 34 supply the rinsing liquid to the original plate P conveyed by the conveying unit 2 in the rinsing region (first rinsing region 13 and second rinsing region 14 described later) adjacent to the downstream side of the developing region. This removes debris from the surface of the original plate P and functions as a rinse liquid supply unit in the present invention. The discharge pipe 33 supplies a new developer containing no used developer as a rinse liquid to the upstream region of the rinse region (first rinse region 13 described later), and serves as a new liquid supply unit in the present invention. Function. The discharge pipe 34 supplies water as a rinse liquid to the downstream region of the rinse region (second rinse region 14 described later), and functions as a water supply unit in the present invention. The discharge pipe 34 supplies the used water stored in the water supply source 71 (described later) as a rinsing liquid.

The brush portion 4 has roll brushes 41, 42, 43, 44. The roll brushes 41, 42, 43, 44 are arranged above the original plate mounting portion 22 and below the discharge pipes 31, 32, 33, 34 so that their respective axes extend substantially horizontally. Elastic hair bundles are arranged on the outer peripheral portions of the roll brushes 41, 42, 43, 44. When the roll brushes 41, 42, 43, and 44 rotate around their respective axes, the tips of the hair bundles move around the axes and are repeatedly arranged on the original plate mounting portion 22 side. The roll brushes 41 and 42 are arranged in the developing region and remove the unexposed portion by rubbing the surface of the original plate P, and function as the unexposed portion removing portion in the present invention.

As shown in FIG. 1, the developing apparatus 1 can be divided into a first developing region 11, a second developing region 12, a first rinsing region 13, and a second rinsing region 14. The first developing region 11, the second developing region 12, the first rinsing region 13, and the second rinsing region 14 are arranged so as to be arranged in this order in the direction in which the original plate P is conveyed. The discharge pipe 31 and the roll brush 41 are arranged in the first development area 11, the discharge pipe 32 and the roll brush 42 are arranged in the second development area 12, and the discharge pipe 33 and the roll brush 43 are arranged in the first rinse area 13. Is arranged, and a discharge pipe 34 and a roll brush 44 are arranged in the second rinse region 14.

In the first developing region 11, the developer is discharged from the discharge pipe 31 and supplied to the surface of the original plate P. As will be described later, the developer discharged here contains the used developer and contains debris. Further, the roll brush 41 rotates, and the hair bundle rubs the surface of the original plate P. As a result, the uncured photosensitive resin is scraped from the surface of the original plate P and discharged together with the developer. The original plate P that has passed through the first developing region 11 then reaches the second developing region 12.

In the second developing region 12, the developer is discharged from the discharge tube 32 and supplied to the surface of the original plate P. As will be described later, the developer discharged here is obtained by filtering a used developer, and debris is almost removed. Further, the roll brush 42 rotates, and the hair bundle rubs the surface of the original plate P. As a result, the uncured photosensitive resin is scraped from the surface of the original plate P and discharged together with the developer. The original plate P that has passed through the second development region 12 then reaches the first rinse region 13. The second development region 12 in the present embodiment is a region including the downstream end of the development region and occupies 10 to 20% of the entire development region. The ratio of the second development area 12 to the entire development area is not limited to this, and can be appropriately changed according to the specifications of the apparatus and the like.

In the first rinse region 13, the developer is discharged from the discharge pipe 33 and supplied to the surface of the original plate P. As will be described later, the developer discharged here is a new developer that does not contain a used developer. Further, the roll brush 43 rotates, and the hair bundle rubs the surface of the original plate P. As a result, the debris adhering to the surface of the original plate P is removed, and the debris is discharged together with the developer. The original plate P that has passed through the first rinse region 13 then reaches the second rinse region 14.

In the second rinse region 14, a large amount of water is discharged from the discharge pipe 34 and supplied to the surface of the original plate P. Further, the roll brush 44 rotates, and the hair bundle rubs the surface of the original plate P. As a result, debris and surfactant adhering to the surface of the original plate P are removed.

The original plate P that has been subjected to the development treatment by such a developing apparatus 1 is swollen by a developer or water. The original plate P is dried by a drying device (not shown). In the drying process, the original plate P is promoted to be dried by blowing high temperature air. The dried original plate P is used as a printing plate.

Further, as shown in FIG. 1, the developing apparatus 1 includes a recovery and supply mechanism 5, a new liquid supply mechanism 6, and a water supply mechanism 7.

The recovery and supply mechanism 5 is configured to supply the developer to the first development region 11 and the second development region 12. The recovery / supply mechanism 5 has a drain pan 51 arranged below the discharge pipe 31, a recovery liquid storage tank 52, a filter device 54, and a filtrate storage tank 56.

The drain pan 51 is located below the transport unit 2 and in a portion corresponding to the first development region 11, the second development region 12, and the first rinse region 13. The drain pan 51 is configured to collect the developer discharged downward from the first developing region 11, the second developing region 12, and the first rinsing region 13.

The recovery liquid storage tank 52 is a container capable of storing liquid. The developer recovered by the drain pan 51 flows into and is stored inside the recovery liquid storage tank 52. The developer contains debris scraped from the surface of the original plate P in the first developed region 11 and the second developed region 12, and debris removed from the surface of the original plate P in the first rinse region 13. The debris is dispersed in the developer.

A part of the developer stored in the recovery liquid storage tank 52 is sucked by the pump 53b via the suction pipe 53a and fed to the filter device 54 via the feed pipe 53c. The filter device 54 has a filter (not shown) inside thereof. The developer fed by the feed pipe 53c is supplied into the filter device 54 and passes through the filter. When the developer passes through the filter, the surfactant is removed from the surface of the resin residue dispersed in the developer due to friction with the filter. As a result, in the developer that has passed through the filter, the resin residue agglomerates without adding a flocculant, and agglomerates are generated. In the present specification, such agglomerates and resin residues are collectively referred to as "debris".

The developer in the filter device 54 containing the debris is fed to the filter liquid storage tank 56 via the feed pipe 55. The filtrate storage tank 56 is a container capable of storing liquid. A filter 56a is arranged inside the filtrate storage tank 56. The developer supplied by the supply pipe 55 is supplied into the filtrate storage tank 56 and passes through the filter 56. When the developer passes through the filter 56a, the debris contained in the developer is almost removed. The filtrate storage tank 56 stores the developer from which debris has been substantially removed.

A part of the filtered developer stored in the filtrate storage tank 56 is sucked by the pump 57b via the suction pipe 57a and returned to the recovery liquid storage tank 52 via the feed pipe 57c. By supplying the developer from which the debris has been removed from the filtrate storage tank 56, the concentration of debris decreases in the recovery liquid storage tank 52.

The developer stored in the recovery liquid storage tank 52 is sucked by the pump 58b via the suction pipe 58a and supplied to the discharge pipe 31 of the first developing region 11 via the feed pipe 58c. The discharge pipe 31 discharges the developer and supplies it to the original plate P arranged in the first developing region 11. Specifically, the developer is discharged from one discharge tube 31 toward the two roll brushes 41, and is supplied to the surface of the original plate P via the bristles of these roll brushes 41. The developer supplied in the first developing region 11 drops from the transport unit 2, is collected by the drain pan 51 as described above, and is subjected to a process of removing debris. That is, the developer supplied to the first developing region 11 is repeatedly subjected to the development of the original plate P.

On the other hand, the filtered developer stored in the filtrate storage tank 56 is sucked by the pump 59b via the suction pipe 59a and also into the discharge pipe 32 of the second developing region 12 via the feed pipe 59c. Will be supplied. The discharge pipe 32 discharges the developer and supplies it to the original plate P arranged in the second developing region 12. Specifically, the developer is discharged from one discharge tube 32 toward the two roll brushes 42, and is supplied to the surface of the original plate P via the bristles of these roll brushes 42. The developer supplied in the second developing region 12 drops from the transport unit 2, is collected by the drain pan 51 as described above, and is subjected to a process of removing debris. That is, the developer supplied to the second developing region 12 is also repeatedly subjected to the development of the original plate P.

The new liquid supply unit 6 is configured to supply the developer to the first rinse region 13. The new liquid supply unit 6 has a new liquid supply source 61. The new liquid supply source 61 is a tank for storing a new developing liquid that has not yet been used for developing the original plate P (that is, does not contain debris). The developer of the new liquid supply source 61 is sucked by the pump 63b via the suction pipe 63a and supplied to the discharge pipe 33 of the first rinse region 13 via the feed pipe 63c. The discharge pipe 33 discharges the developer and supplies it to the original plate P arranged in the first rinse region 13. Specifically, the developer is discharged from one discharge tube 33 toward the two roll brushes 43, and is supplied to the surface of the original plate P via the hair bundles of these roll brushes 43. The developer supplied in the first rinse region 13 falls from the transport unit 2 and is collected by the drain pan 51. That is, the developer supplied to the first rinse region 13 by the new liquid supply unit 6 is subjected to a process of removing debris together with the developer supplied to the first development region 11 and the second development region 12. Is supplied to the first development area 11 and the second development area 12.

The water supply unit 7 is configured to supply water to the second rinse region 14. The water supply unit 7 has a water supply source 71. The water supply source 71 is, for example, a tank for storing water supplied from tap water. The water of the water supply source 71 is sucked by the pump 73b via the suction pipe 73a and supplied to the discharge pipe 34 of the second rinse region 14 via the supply pipe 73c. The discharge pipe 34 discharges water and supplies it to the original plate P arranged in the second rinse region 14. Specifically, water is discharged from one discharge pipe 34 toward two roll brushes 44, and is supplied to the surface of the original plate P through the bristles of these roll brushes 44. The water supplied in the second rinse region 14 falls from the transport unit 2 and is collected by the drain pan 75. The water recovered by the drain pan 75 is filtered by a filtration device (not shown) to remove impurities, and is returned to the water supply source 71.

Next, a developing method using the developing apparatus 1 according to the embodiment of the present invention will be described.

First, while the original plate P is conveyed in the predetermined direction A by the conveying unit 2, the developer is supplied to the original plate P in the developing region (first developing region 11 and the second developing region 12) with the roll brushes 41 and 42. The unexposed portion is removed by rubbing the surface of the original plate P (development step). Here, in the developing step, the developing solution containing the used developing solution is supplied to the upstream region (first developing area 11) of the developing region, while the used developing solution is filtered to obtain the filtered development. The solution is supplied to the downstream region (second development region 12) of the development region.

Next, while transporting the original plate P in a predetermined direction A, the original plate P is supplied with a rinse liquid in the rinse region (first rinse region 13 and second rinse region 14) on the downstream side of the developing region. Debris is removed from the surface of the surface (rinse process). Here, the rinsing step includes a new liquid rinsing step of supplying a new developing liquid containing no used developing liquid as a rinsing liquid to the upstream region (first rinsing region 13) of the rinsing region, and rinsing with water as the rinsing liquid. A water rinsing step of supplying to the downstream region (second rinsing region 14) of the region is included. After that, the original plate P is dried by a drying device (not shown) to obtain a printing plate.

In the developing apparatus 1 according to the above-described embodiment, development can be performed using the filtered developer in the latter half of the developing step (that is, the second developing region 12), so that the debris brought into the rinse region can be developed. The amount can be significantly reduced. Therefore, it is possible to reduce the amount of the rinsing solution (new developer or water) used in the rinsing process, and it is also possible to reduce the amount of debris adhering to the original plate P that has undergone the rinsing process. , There is no need to make major modifications to the drive mechanism of the roll brushes 41 and 42. Further, in the first half of the developing process (that is, the first developing region 11), since the used developing solution is reused for development, the new developing solution can be saved and the labor of filtering the entire amount of the developing solution can be saved. Can be omitted.

Further, in the developing device 1 according to the above-described embodiment, the new liquid supply unit that supplies the new developing solution containing no used developer as a rinsing solution to the upstream region (first rinsing region 13) of the rinsing region. Since it has 6 and a water supply unit 7 that supplies water as a rinsing solution to the downstream region (second rinsing region 14) of the rinsing region, rinsing is performed in two steps using a new developer and water. Can be done. Therefore, debris can be efficiently removed from the original plate P.

Further, in the developing apparatus 1 according to the above-described embodiment, the used water stored in the water supply source 71 is supplied as a rinsing solution, but the filtered developing solution is used in the latter half of the developing step. Since the development is performed, the amount of debris adhering to the original plate P at the time of water rinsing is small, so that the amount of debris mixed in the water is small, and the stored water can be used more continuously.

The present invention is not limited to the above embodiments, and those having a design modification appropriately by those skilled in the art are also included in the scope of the present invention as long as they have the features of the present invention. .. That is, each element included in the embodiment and its arrangement, material, condition, shape, size, etc. are not limited to those exemplified, and can be appropriately changed. Further, the elements included in the embodiment can be combined as much as technically possible, and the combination thereof is also included in the scope of the present invention as long as the features of the present invention are included.

1 ... Developing device 2 ... Conveying unit 31 ... Discharge tube (first developer supply unit, developer supply unit)
32 ... Discharge tube (second developer supply unit, developer supply unit)
33 ... Discharge pipe (new liquid supply unit, rinse liquid supply unit)
34 ... Discharge pipe (water supply unit, rinse liquid supply unit)
41.42 ... Roll brush (unexposed part removal part)
71 ... Water supply source P ... Original version

Claims (8)

A device for developing an original plate having a photosensitive resin layer on its surface.
A transport unit in which an exposed portion and an unexposed portion are formed on the photosensitive resin layer and the original plate is conveyed in a predetermined direction.
A developer supply unit that supplies a developer in the developing region to the original plate conveyed by the transfer unit,
An unexposed portion removing portion, which is arranged in the developing region and removes the unexposed portion by rubbing the surface of the original plate,
The original plate transported by the transport unit is provided with a rinse liquid supply unit for removing debris from the surface of the original plate by supplying the rinse liquid in the rinse region adjacent to the downstream side of the development region.
The developer supply unit is a first developer supply unit that supplies a developer containing a used developer to the upstream region of the developer region, and a filtered developer obtained by filtering the used developer. A developing apparatus having a second developer supply unit that supplies the liquid to the downstream region of the developing region. The rinse liquid supply unit includes a new liquid supply unit that supplies a new developer containing no used developer to the upstream region of the rinse region as the rinse liquid, and a new liquid supply unit that supplies water as the rinse liquid downstream of the rinse region. The developer according to claim 1, further comprising a water supply unit for supplying a side region. The developing device according to claim 2, wherein the water supply unit supplies used water stored in a water supply source as a rinsing liquid. The developing apparatus according to any one of claims 1 to 3, wherein the downstream region of the developing region is a region including the downstream end of the developing region and occupying 10 to 20% of the entire developing region. A method of developing an original plate having a photosensitive resin layer on its surface.
While transporting the original plate in which the exposed portion and the unexposed portion are formed on the photosensitive resin layer in a predetermined direction, the developing solution is supplied to the original plate in the developing region, and the unexposed portion removing portion of the original plate. A developing step of removing the unexposed portion by rubbing the surface, and
A rinsing step of removing debris from the surface of the original plate by supplying a rinse liquid to the original plate in a rinse region adjacent to the downstream side of the development region while transporting the original plate that has undergone the development step in the direction. , Including
In the developing step, the developer containing the used developer is supplied to the upstream region of the developing region, while the filtered developer obtained by filtering the used developer is supplied to the downstream side of the developing region. A developing method that supplies the area. The rinsing step includes a new liquid rinsing step of supplying a new developer containing no used developer to the upstream region of the rinsing region as the rinsing liquid, and a downstream region of the rinsing region using water as the rinsing liquid. 5. The developing method according to claim 5, further comprising a water rinsing step of supplying to. The developing method according to claim 6, wherein in the water rinsing step, used water stored in a water supply source is supplied as a rinsing liquid. The developing method according to any one of claims 5 to 7, wherein the downstream region of the developing region is a region including the downstream end of the developing region and occupying 10 to 20% of the entire developing region.

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