JP2014210861A - Mold releasability recovery liquid, mold releasability recovery method, and photomask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold releasability recovery liquid which is useful for recovering deteriorated mold releasability of a coating film including silicone oil.SOLUTION: A mold releasability recovery liquid comprises only a releasability recovery component and a solvent, and the releasability recovery component comprises a reactive silicone oil and a non-reactive silicone oil. Preferably, 3-5 pts.wt. of the reactive silicone oil is contained with respect to 1 pt.wt. of the non-reactive silicone oil. Preferably, a weight ratio of the releasability recovery component to the solvent is 4:96 to 6:94.

Description

  The present invention relates to a release performance recovery liquid suitable for use when the release performance of a coating film containing silicone oil is lowered, a release performance recovery method using the solution, and a release performance using the method. The present invention relates to a photomask obtained by laminating a protective film that has been restored to a thin film pattern (image) surface of a glass mask.

  When producing printed wiring boards and resin relief plates, the photomask that has been subjected to contact exposure to an adhesive photoresist is pulled away from the photoresist, and the resist facing surface is washed with a solvent, and then applied to another photoresist. In contrast, it is used repeatedly. Conventionally, for the purpose of preventing a reduction in exposure accuracy during repeated use, a coating film having releasability is formed on the thin film pattern surface of the photomask, or a surface protective film provided with such a coating film. (Patent Documents 1 and 2). This prevents the photoresist from remaining on the thin film pattern surface of the photomask after cleaning with a solvent.

Japanese Patent Laid-Open No. 2000-273412 (paragraph number 0008) Japanese Patent Laying-Open No. 2005-181565 (paragraph number 0005)

  Many coating films having releasability include silicone oil as a release component in a binder resin. In such a coating film, the mold release performance decreases as the use frequency of the photomask increases. For this reason, after repeated use to some extent, it is necessary to re-form a new coating film on the photomask, or to prepare a photomask having the same pattern separately, and a product (printed wiring board, resin letterpress, etc.). The same)) had a problem in terms of productivity.

  In one aspect of the present invention, a release performance recovery liquid useful for recovering the reduced release performance of a releasable coating film is provided. In another aspect, there are also provided a mold release performance recovery method capable of efficiently recovering the mold release performance of the mold release coating film and a photomask having the mold release performance recovered using the method. .

  The inventors of the present invention have taken measures to improve the product productivity without forming a new coating film on the photomask after repeated use or separately preparing a photomask having the same pattern as the photomask. investigated. As a result, the inventor has conceived a new problem that it is only necessary to recover the degraded release performance. Then, a solution obtained by diluting a specific performance recovery component with a large amount of solvent is found to be effective in recovering the reduced release performance of the coating film containing silicone oil having release properties, and the present invention has been completed. It was.

  In addition, the coating film containing silicone oil in the present invention has a mold release performance, for example, a manuscript (photophotograph) when exposing a sticky photoresist (liquid photoresist or the like) in a printed circuit board manufacturing process or the like. It is used as a protective film formed on or attached to the surface of a mask).

  The mold release performance recovery liquid of the present invention is used to recover the mold release performance of a coating film containing silicone oil. This recovery liquid is composed only of a performance recovery component and a solvent, and the performance recovery component is composed of a reactive silicone oil and a non-reactive silicone oil.

  The release performance recovery method of the present invention is a method of recovering the reduced release performance of the coating film containing silicone oil, and the release performance recovery liquid of the present invention is the target coating film (release performance has been reduced, (Coating film containing silicone oil) and dried under the following conditions. Temperature: 85 ° C. to 130 ° C., Time: 5 minutes to 15 minutes.

  The photomask of the present invention was deteriorated by applying the release performance recovery method of the present invention to a protective film containing silicone oil laminated on the thin film pattern surface of a glass mask having a thin film pattern on a glass substrate. It is characterized by having improved mold release performance.

The present invention includes the following aspects.
(1) In the release performance recovery liquid, the content ratio in the performance recovery component is set such that the reactive silicone oil is 1.5 parts by weight or more and 7 parts by weight or less (particularly 3 parts by weight) with respect to 1 part by weight of the non-reactive silicone oil. Parts by weight or more and 5 parts by weight or less).
(2) In the release performance recovery liquid, the weight ratio of the performance recovery component and the solvent can be 2.5: 97.5 to 8:92 (particularly 4:96 to 6:94).

(3) In the mold release performance recovery method, the drying conditions can be set to temperature: 90 ° C. or more and 120 ° C. or less, and time: 8 minutes or more and 12 minutes or less.
(4) As a glass mask used for forming the protective film, a chromium mask in which a thin film pattern is formed of a chromium material can be used.

Since the release performance recovery liquid of the present invention contains a specific performance recovery component, it is useful for recovering the reduced release performance of a coating film having releasability.
In the release performance recovery method of the present invention, a solution containing a specific performance recovery component is applied to a target coating film and dried under specific conditions, so that the release performance of the coating film having releasability is effectively reduced. Can be recovered.

  In the photomask of the present invention, the reduced release performance is recovered by applying the release performance recovery method of the present invention to the protective film having a reduced release performance, so that the exposure mask is used repeatedly. be able to. As a result, the repeated use resistance of one photomask is increased, and as a result, the productivity of the product is improved.

First, the structural example of the mold release performance recovery liquid of this invention is demonstrated.
The mold release performance recovery liquid of this example is composed only of a performance recovery component and a diluent solvent, and does not contain a so-called binder component. Since it does not contain a binder component, it is easy to form a thin film, and only the releasability can be recovered while maintaining the performance (hardness, transmittance, etc.) of the protective film.

  The performance recovery component of this example is used to recover the reduced release performance of a coating film containing silicone oil. This component is composed of a mixture of reactive and non-reactive silicone oils.

  The reactive silicone oil of this example includes a modified silicone oil in which a part of the methyl group of dimethylpolysiloxane is substituted with a reactive functional group. Examples of the reactive functional group include an alkoxy group, a mercapto group, a carbinol group, an epoxy group, an amine group, an acrylic group, and a carboxyl group. These reactive silicone oils can be used alone or in combination of two or more.

  The reactive silicone oil preferably includes those having a silanol group, those having a carbinol group, and more preferably those having a silanol group. When a reactive silicone oil having a silanol group is included, it can be expected to maintain the release performance after recovery for a longer period.

  Specific examples of reactive silicone oils include amino-modified (KF393, KF8004, KF861, KF8010, etc.), epoxy-modified (KF101, X-22-4741, X-22-163) as trade names of Shin-Etsu Chemical Co., Ltd. , X-22-173DX, etc.), carbinol modification (X-22-4039, X-22-4015, X-22-160AS, KF6001, KF6003 etc.), hydrogen modification (KF9901 etc.), methacryl modification (X- 22-164C, X-22-174DX, etc.), carboxyl modification (X-22-162C etc.), silanol modification (KF9701 etc.), side chain amino-terminal methoxy modification (KF857, KF858 etc.), etc. are mentioned.

  The non-reactive silicone oil of this example is a non-functional silicone oil or a non-functional silicone resin in which a part of the methyl group of dimethylpolysiloxane is substituted with a polyether group, a phenyl group, an alkyl group, an aralkyl group, a fluorinated alkyl group, etc. Contains modified silicone oil. These non-reactive silicone oils can be used alone or in combination of two or more.

  Non-reactive silicone oils preferably include long chain alkyls and polyethers, and more preferably long chain alkyls.

  Specific examples of the non-reactive silicone oil include polyether-modified (KF352A, KF353, KF354L, KF355A, KF615A, KF643, KF6011, KF6012, KF6012, KF6015), dimethylsilicone oil (trade name) of Shin-Etsu Chemical Co., Ltd. KF96, etc.).

  In this example, the reactive silicone oil is preferably 1.5 parts by weight or more, more preferably 3 parts by weight or more, preferably 7 parts by weight or less, with respect to 1 part by weight of the non-reactive silicone oil. More preferably, it may be contained in an amount of 5 parts by weight or less (when a plurality of types of reactive silicone oils are contained, the total amount). By containing an appropriate amount of the reactive silicone oil, it can be expected to maintain the release performance after recovery for a longer period of time. Note that if the content of the reactive silicone oil is too large, it may not react and may bleed and transfer, but the present invention does not necessarily limit the content of the reactive silicone oil in the liquid. Absent.

  Examples of the dilution solvent include methyl ethyl ketone, cyclohexanone, butanol, isopropyl alcohol and the like. These solvents can be used alone or in combination of two or more.

  In this example, the weight ratio of the performance recovery component and the diluent solvent is preferably 2.5 wt% or more and 8 wt% or less for the former, 92 wt% or more and 97.5 wt% or less for the latter, and more preferably 4 wt% for the former. It is preferable that the weight is not less than 6% by weight and not more than 6% by weight, and the latter is not less than 94% by weight and not more than 96% by weight. By including a performance recovery component in an appropriate amount in the liquid, an effect of improving the releasability can be expected. In addition, when there is too much content of the performance recovery component in the liquid, interference unevenness to the coating film is likely to occur and there is a tendency to transfer to the resist, but in the present invention, the content of the performance recovery component in the liquid No limitation is essential.

  Since the release performance recovery liquid of this example contains the specific performance recovery component described above, it is useful for recovering the release performance of the coating film having release properties. By using this recovery liquid, it is possible to improve the productivity of the deliverables (exposure efficiency and cost reduction).

Next, an application example of the release performance recovery liquid of the present invention will be described.
The mold release performance recovery liquid of this example can be applied to a glass mask in which a protective film containing silicone oil is laminated on a thin film pattern surface on a glass substrate, for example. Hereinafter, application to this glass mask will be described as an example.

  A glass mask as an example to which the release performance recovery liquid of this example can be applied is a thermosetting protective liquid having a predetermined composition (in this example, a silicone resin) on the thin film pattern surface of the mask body used for forming the protective film. And a protective film composed of a cured product obtained by applying heat to this and curing it.

The mask main body is formed with a thin film pattern for forming a fine pattern on a printed wiring board or a resin relief plate on a glass substrate. Examples of such a mask main body include a thin film pattern formed by applying an emulsion of gelatin and silver halide on a glass substrate (emulsion mask), and a chromium material (such as chromium or chromium oxide) on the glass substrate. Examples include a thin film pattern (chrome mask) formed. This example is effective for application particularly when a chrome mask is used as the mask body.
In addition, the mask main body used in this example includes one in which an undercoat layer for improving adhesion to a protective film is provided on a glass substrate.

The glass mask applied in this example is a cured product obtained by applying a thermosetting protective liquid to the entire surface of the thin film pattern surface of the mask body and then polymerizing (thermosetting) the resin component of the protective liquid by applying heat. This is used as a protective film having hard coat properties and releasability. Protection with excellent adhesion to mask body, hard coat property (pencil hardness according to JIS-K5600-5-4: 1999) and light resistance by including silicone resin and epoxy resin in protective liquid The glass mask has a film.
However, it cannot be denied that the release performance of the protective film is lowered gradually as the use (frequency of use) as a photomask increases. Therefore, in this example, by applying the recovery liquid of this example, the mold release performance with the reduced protective film is recovered.

Next, an example of the release performance recovery method of the present invention will be described.
In the release performance recovery method of this example, the release performance recovery liquid of this example is applied to the target coating film. In this example, the target coating film is a protective film containing a thermosetting product of silicone resin and epoxy resin and silicone oil, and may be applied when the release performance of the film is deteriorated.
In this example, the deterioration of the mold release performance is assumed, for example, when the remaining of the photoresist is recognized on the coating film of the photomask after predetermined cleaning (solvent cleaning).

  The coating method is not limited, and known methods such as dip coating, spin coating, die coating, cap coating, and bar coating can be used. The coating amount may be increased or decreased according to the degree of degradation of the release performance. However, if the coating amount is too large, inconveniences such as uneven interference and transfer occur, and if it is too small, it is difficult to obtain the effect. Then, it is good to apply | coat with the quantity from which a dry film thickness will be about 50-300 nm, for example.

  Next, the applied recovery liquid is dried under specific conditions. The drying temperature may be about 85 ° C. or higher and 130 ° C. or lower, and preferably 90 ° C. or higher and 120 ° C. or lower. If this temperature is too high, it may cause inconvenience in the hard coat performance of the substrate, and if it is too low, inconvenience in mold release performance may occur. The drying time may be about 5 minutes to 15 minutes, preferably about 8 minutes to 12 minutes. If the drying time is too long, handling problems may occur.

  In the release performance recovery method of this example, a solution containing a specific performance recovery component is applied to the target coating film and dried under specific conditions, so that the release performance with a reduced protective film is effectively recovered. As a result, the glass mask after application of the present method can be used for repeated exposure operations. As a result, the repeated use resistance of one glass mask increases, and as a result, the productivity improvement of a product is achieved.

  The following examples further illustrate the present invention. “Parts” and “%” are based on weight unless otherwise specified.

<1. Production of glass mask>
A thermosetting protective liquid for glass mask having the following composition is applied onto a patterned chromium mask by spin coating, and heated and cured at 150 ° C. for 70 minutes to form a protective film having a thickness of about 2 μm. Was made.

<Composition of thermosetting protective liquid for glass mask>
・ 10 parts of silicone resin (solid content 100%) (KR400: manufactured by Shin-Etsu Co., Ltd.)
・ 10 parts of epoxy resin (solid content: 100%) (EPPN502H: manufactured by Nippon Kayaku Co., Ltd.)
・ 0.3 parts of silicone oil (100% solid content) (X-22-4272: manufactured by Shin-Etsu Co., Ltd.)
・ Methyl ethyl ketone (diluting solvent) 79.2 parts ・ Curing agent (solid content 100%) 0.5 parts (IB2PZ: manufactured by Shikoku Chemicals)

<2. Pseudo-evaluation of glass mask peeling performance>
2-1. Change in peel strength A photoresist composed of an ultraviolet curable resin was brought into close contact with the protective film surface of the produced glass mask (step 1). Next, the surface of the glass mask on which the protective film is not formed (the back surface of the glass mask) is irradiated with ultraviolet rays (adhesion exposure), the photoresist is UV-cured in a predetermined pattern, and the exposed photoresist is then applied to the glass mask. (Step 2). Next, the protective film surface of the glass mask separated from the photoresist was washed with a solvent to prepare a glass mask for the next exposure (step 3).
After performing the operations in the above steps 1 to 3 100 times, an adhesive tape (Cellotape CT405AP-18: Nichiban Co., Ltd.) was attached to the protective film of the glass mask. In this state, a 180 ° peeling force at a peeling speed of 300 mm / min was measured using a tensile test (Shimadzu small tabletop testing machine EZ-L: Shimadzu Corporation).
As a result, when the peel force is less than 1 N / 18 mm, after determining that “there is a release property”, the operations of steps 1 to 3 are further performed 100 times, and the 180 ° peel force is measured again under the same conditions. did. And when this measurement result became 1N / 18mm or more, it was judged that "no mold release property", ie, "the mold release performance was lowered". In this example, after performing the operations of Steps 1 to 3 500 times, it was confirmed that the mold release performance was lowered.

2-2. Change in contact angle The contact angle of pure water on the protective film surface of the produced glass mask was measured immediately after the mask production, and at the respective timings after the operations of steps 1 to 3 were performed 100 times, 200 times, and 500 times. . And when the value of the contact angle was 90 degrees or more, it was judged as “antifouling”, and when it was less than 90 degrees, it was judged as “no antifouling”. In addition, the value of the contact angle was taken as the average value of the measured values obtained by repeating the dropping and the measurement three times for the measured value of the contact angle one minute after dropping pure water. In this example, the deterioration of the antifouling performance was confirmed after the operations of Steps 1 to 3 were performed 500 times.

<3. Preparation of recovery liquid>
The release performance recovery liquid of each example was produced with the composition of Table 1 below.

In Table 1, reactive silicone oil (DMS-S15: manufactured by Gelest, solid content 100%, average molecular weight 2750, viscosity (25 ° C.) = 65 cSt), non-reactive silicone oil (KF-96-100 cs: manufactured by Shin-Etsu) , Solid content 100%, viscosity (25 ° C.) = 1000 × 10 ³ cSt), and diluting solvent (methyl ethyl ketone).

<4. Evaluation of recovery liquid>
About the release performance recovery liquid produced in each example, the recovery degree of the release performance when each recovery liquid was applied was evaluated. Specifically, the evaluation was performed according to the following procedure.
2-1. Steps 1 to 3 were repeated 500 times to prepare a glass mask having a protective film with reduced release performance. After applying the release performance recovery liquid of each example of the prepared composition of Table 1 to the prepared protective film of the glass mask in an amount such that the dry film thickness is about 200 nm, the liquid was dried under the drying conditions described in Table 1. . For the glass mask having a protective film after drying, the above 2-1. After performing Steps 1 to 3 in 700 times, the above 2-1. “Change in peel strength” and 2-2. The “change in contact angle” was evaluated.

  Specifically, “◎” indicates that the peel force in the “change in peel strength” is less than 0.2 N / 18 mm, and “○” indicates that the peel force is 0.2 N / 18 mm or more and less than 0.7 N / 18 mm. ”, Those that were 0.7 N / 18 mm or more and less than 1 N / 18 mm were designated as“ Δ ”, and those that were 1 N / 18 mm or more were designated as“ X ”. Also, “◎” indicates that the contact angle value in the “change in contact angle” is 98 degrees or more, and “◯” indicates that the contact angle value is 95 degrees or more and less than 98 degrees, and “◯” is 90 degrees or more and less than 95 degrees. Is “Δ”, and the case of less than 90 degrees is “x”. The results are shown in Table 1.

<5. Discussion>
The usefulness of the release performance recovery liquid in each case was confirmed. In particular, the usefulness of the experimental examples 3 to 5 was recognized.

<6. Other experimental examples>
Instead of the reactive silicone oil used in Experimental Examples 1 to 7, another reactive silicone oil (DMS-S21: manufactured by Glest, solid content 100%, average molecular weight 4200, viscosity (25 ° C.) = 110 cSt) was used. In this case, the same result as in Table 1 was obtained.

Further, instead of the non-reactive silicone oil used in Experimental Examples 1 to 7, another non-reactive silicone oil (KF6001: manufactured by Shin-Etsu Co., Ltd., solid content 100%, viscosity (25 ° C.) = 45 × 10 ³ cSt) was used. When used, the same results as in Table 1 were obtained.

Claims (6)

A release performance recovery liquid used for recovering the reduced release performance of the coating film containing silicone oil, which is composed of only a performance recovery component and a solvent,
A release performance recovery liquid, wherein the performance recovery component is composed of a reactive silicone oil and a non-reactive silicone oil.   The release liquid according to claim 1, wherein the reactive silicone oil is contained in an amount of 3 parts by weight or more and 5 parts by weight or less based on 1 part by weight of the non-reactive silicone oil. Recovery liquid.   The recovery liquid according to claim 1 or 2, wherein a weight ratio of the performance recovery component and the solvent is set to 4:96 to 6:94. A method for recovering the reduced release performance of a coating film containing silicone oil,
A method for recovering mold release performance, comprising applying the recovery liquid according to any one of claims 1 to 3 to a target coating film and drying it under the following conditions.
Temperature: 85 ° C. or higher and 130 ° C. or lower,
Time: 5 minutes or more and 15 minutes or less.   In a photomask in which a protective film containing silicone oil is laminated on the thin film pattern surface of a glass mask having a thin film pattern on a glass substrate, the method according to claim 4 is applied to the protective film to reduce mold release. Photomask with improved performance.   6. The photomask according to claim 5, wherein a chromium mask in which a thin film pattern is formed of a chromium material is used as the glass mask.