JPS6061745A - Peeling development method - Google Patents

Abstract

PURPOSE:To enhance image reproducibility by specifying thicknesses of the base and the adhesive layer of an adhesive tape in order to form an image through a peeling development method, applying the adhesive tape to all the region on the peeling courses, anc executing peeling in this state. CONSTITUTION:An image forming material composed of a transparent support and a photopolymerizable layer is laminated on the surface of an image forming base, and after the exposure to the light image of a pattern having many corners, said image forming material is peeled from the base with a roll, leaving the layer of the exposed photopolymerized parts on the base. Adhesive tape each composed of a 150mum thick base and a 5-50mum thick adhesive layer are applied to all the region of the peeling courses of the supporting surface, and the peeling is executed in this state. The support thus treated is made not flexible at all by peeling, and it appears like a rigid sheet, so the peeling course at the corner parts causes no delay but keeps straight, and the reproducibility of the image can be enhanced without leaving any unexposed corner parts of the base.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a peeling and developing method used for manufacturing printed circuits and the like.

For the production of printed circuits, etc., the photopolymerizable composition layer side of an image forming material consisting of a transparent support and a photopolymerizable composition layer coated on this support is placed on the surface of an image forming substrate. This photopolymerizable composition layer is imagewise exposed to light to form a cured area, and if necessary, the image-forming material is heated, and then the support is peeled from the substrate. Second, an image forming means for forming an image-like resist has already been devised.

On the other hand, various methods for peeling off image forming materials of the peel development type described above have also been proposed. As one method, a method has been proposed in which the unexposed portion to be peeled off from the substrate along with the support is separated from the substrate while being sandwiched between a pressure/peel roll and a nip roll.

In this method, there are two methods: one in which adhesive tapes are attached in sequence to the support on the image side of the board and then peeled off together with the adhesive tape; In this method, a peelable edge piece protruding from the substrate is provided as a so-called ear tape at one end of the film-like support of the substrate, and by pulling this peelable edge piece, the peelable edge piece is continued from the peelable edge piece. There is a method of peeling off the above-mentioned support.

However, all of these methods may lack image reproducibility due to fluctuations in the substrate during peeling. In particular, when forming a pattern 10 with many corner parts as shown in FIG.
There is a problem in that the unexposed portion 11 tends to remain on the leading edge side in the direction (direction).

Regarding this problem, we will take as an example a case where a peelable end piece protruding from the substrate is provided at one end of a film-like support on a substrate and peeling is performed by pulling this peelable piece, as shown in FIG.
5), (B), (This will be explained in more detail based on C1.

In the figure, 1 is an image forming substrate, 2 is an image forming material layer adhered to the main surface of the substrate 1, and this includes a photopolymerizable composition layer 3 and a transparent support 4 supporting this layer 3. Consisting of 5 is a pressure bonding/peeling roll, 6 is a nip roll, R
is the peeling progression line.

When the two rolls 5 and 6 start peeling, the support 4 is peeled off along with the unexposed portion 3b along the surface of the pressure/peeling roll 5, as shown in FIG. 3(3).

However, the peeling force against the support 4 changes depending on the difference in adhesive strength between the exposed portion 3a and the unexposed portion 31) of the photopolymerizable composition layer 3 and the substrate 1. When this peeling force suddenly increases, the support body slips, resulting in a slack portion in the support body 4 as shown in FIG. 1 (I3). It won't follow the surface. In this case, the peeling angle of the support 4 etc. is determined by the thickness and rigidity of the support, the balance between the torque and peeling force applied to the pressure/peel roll 5 and the nip roll 6, etc. Therefore, in extreme cases, both The support is moved to the point where the distance between the clamping position P by the rolls 5°6 and the peeling progression line R on the substrate 1 is the shortest, that is, the position where the support 4 is peeled off at an angle of 90° to the main surface of the substrate 1. 4 is pulled, the substrate 1 is displaced in the direction of the black arrow, and thereafter peeling is performed in the state shown in FIG. 4(C). .

When peeling is performed with the support 4 sagging in this way, the state of the peeling progression line seen from above the substrate is shown in the third diagram.
As shown in the figure. In the figure, 1 is an image forming substrate, 4 is a support, 10 is a pattern consisting of exposed areas, 11 is a piece left behind in an unexposed area, and R is a peeling progress line. As shown in the figure, the peeling progression line R is not a straight line, and there is a delay at a corner S. This delay is transparent support strength month 0-30
This is because it is thin and flexible as pm,
Due to this delay and a change in the peeling angle due to the sagging of the support, a peeling force is applied to the unexposed portion of the corner portion S to lift the unexposed portion planarly above the substrate.

Generally, in this type of image forming material, the cohesive force of the photopolymerizable composition layer is set to be relatively small so that the unexposed area of the photopolymerizable composition layer can be separated from the exposed area from any angle with respect to the substrate of the support. It is designed so that it can be easily separated. However, on the contrary, the above-mentioned division may occur from any part of the unexposed area of the photopolymerizable composition layer, resulting in a disordered image, and this is especially true when a peeling force is applied as described above. Rather than the exposed portion peeling off from the substrate, cohesive failure occurs in the unexposed portion, leaving pieces left behind at some corners.

The same phenomenon occurs when such a piece is left behind even when an intermediate adhesive tape is applied and then peeled off. In other words, this is because the adhesive tape is only partially attached, and at the same time, the adhesive tapes conventionally used for such peeling are not rigid enough to cause the delay in the peeling progress line as mentioned above. This is because it does not have

The present invention was made in order to eliminate the above-mentioned drawbacks when forming a pattern with many corners. That is, in this invention, an image forming material consisting of a transparent support and a photopolymerizable composition layer is laminated on the surface of a substrate on which an image is to be formed, and after exposure is performed in a pattern with many corners, pressure bonding is performed. - A peeling development method in which the support and the unexposed photopolymerizable composition layer are peeled off from the substrate described in "2" using a peeling roll and a nip roll, and the exposed photopolymerizable composition layer remains on the substrate. , characterized in that the above peeling is carried out with an adhesive tape having a base material thickness of 10 to 150 μm and an adhesive layer thickness of 5 to 50 μm attached over at least the entire area on the peel progression line on the surface of the support. This relates to a peeling development method.

According to the method of the present invention, the support to which the adhesive tape is attached at least over the entire area on the peeling progression line does not exhibit its own flexibility during peeling.
Since the sheet has apparent rigidity, the peeling progression line becomes a straight line without any delay even at the corners, and no unexposed portions at the corners are left behind on the substrate.

The adhesive tape used in the method of this invention has a base material thickness of 0 to 150 pms, preferably 50 to 150 pm.
0, Ilm. If the thickness is less than 10 μm, it is not possible to obtain the necessary rigidity during peeling, and if it exceeds 150 μm, the rigidity is too large and it becomes difficult to follow the roll, which is not preferable. Preferred materials for this base material include paper such as kraft paper, and plastic films such as cellophane, polyester, polypropylene, polyacetate, polyimide, polytetrafluoroethylene, polyvinyl fluoride, and polycarbonate. In addition, the thickness of the adhesive layer of this tape is 5~
50 μm, preferably 20 to 50/Im.

If this thickness is less than 5 pm, the adhesive strength of the adhesive tape will be lower than the adhesive strength of the unexposed area to the substrate surface on which an image is to be formed, and the adhesive tape may peel off the unexposed area from the substrate together with the transparent support. This is not preferable because it makes it impossible to do so.

Moreover, if this thickness exceeds 50 μ7n, the cohesive force of the adhesive layer of the adhesive tape decreases, and the adhesive layer and the support are likely to shift during the gap when peeling is attempted.

Therefore, as with the drawbacks of the conventional method, the φ+S progression line is not a straight line, and there is a delay at some corners, which is undesirable because unexposed areas at some corners are likely to remain.

The adhesive used to form this adhesive layer is a rubber adhesive made by adding a tackifier, a softener, etc. to natural rubber or one of its derivatives, various synthetic rubbers, or a blend of these rubbers. agent, butyl acrylate, 2
- Acrylic pressure-sensitive adhesives containing a copolymer of ethylhexyl acrylate, other acrylic monomers, etc. as a main component, and optionally containing a crosslinking agent or the like are preferred.

The adhesive strength of this adhesive tape is preferably 180° peeling adhesive strength of about 600 to 3,000 g 1/25 width.

Specific examples of such adhesive tapes include, for example, 718 Kraft Adhesive Tape, manufactured by Nitto Electric Industry Co., Ltd.
375 Danpron tape etc. are mentioned. Note that the width of the adhesive tape used is equal to or larger than the width of the support on the peeling progression line.

In the method of the present invention, when the support is peeled off after exposure, the adhesive tape is stuck to at least the entire area on the peeling progression line of the support surface, and the adhesive tape and the support are integrated. Perform peeling.

To explain this based on the drawings, FIG. 4 shows that the above-mentioned adhesive tape 7 is applied in advance to the entire surface of the support after exposure by a conventional method such as roll lamination, and then peeled off.

In the figure, 8 is a base material of the adhesive tape, and 9 is an adhesive layer. Further, in FIG. 5, the adhesive tape 7 is sequentially attached to the surface of the support and peeled off, and any of these methods may be employed. 4 and 5, the degree of sagging of the support body corresponds to that in FIG.
Even in cases corresponding to No. 1, peeling can be performed satisfactorily.

Note that although the case where the image forming material is laminated on only one side of the substrate is shown in each side above, the method of the present invention can also be applied to the case where the image forming material is laminated on both sides of the substrate.

Examples of this invention will be described below.

EXAMPLE As an image forming material, "Neodorock-T" manufactured by Nitto Electric Industry Co., Ltd. was used.
After exposure was carried out using a photomask with many corners as shown in the figure, "X 718 Kraft Adhesive Tape" (trade name, manufactured by Nitto Electric Industries, Ltd.) was adhered to the entire surface of the support. Then, when peeling was performed as shown in Figure 4, 1
Clear images were obtained with no unexposed areas remaining on any of the 0 sheets.

On the other hand, the second one without pasting the above adhesive tape
When peeling was performed in the state shown in figure (B) or (C) 1
For 5 to 6 out of 0 sheets, a portion of the corner remained unremoved.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of unexposed areas left in some corners of the pattern, Figures 2 (A), (B),
(C) is a cross-sectional view showing the conventional peeling development method, FIG. 3 is a plan view showing the above method, and FIGS. 4 and 5 are cross-sectional views showing the peeling developing method of the present invention. 61...Substrate , 2・
Image forming material, 3-photopolymerizable composition layer, 3a/exposed area,
3b...unexposed area, 4 transparent support, 5 pressure/peel roll, 6 nip roll, 7 adhesive tape, 8...
・Basic shrine, 9...Adhesive layer, R・Peeling progression line Patent applicant Nitto Electric Industry Co., Ltd.

Claims (1)

[Claims] (1) An image forming material consisting of a transparent support and a photopolymerizable composition layer is laminated on the surface of a substrate on which an image is to be formed, and after exposure in a pattern with many corners,
In a peeling development method in which the support and the unexposed photopolymerizable composition layer are peeled from the substrate using a peeling roll and a nip roll, and the exposed photopolymerizable composition layer remains on the substrate, the peeling , the thickness of the base material is 10 to 150
Adhesive tape whose thickness of the adhesive layer is 5 to 50 μm in pm,
- A peeling and developing method characterized in that the peeling and developing method is carried out in a state where the film is adhered over at least the entire area on the peeling progression line on the surface of the support.