TW202224951A - Laminate - Google Patents

Abstract

A laminate comprising a silicone layer and a polyimide layer, wherein the weight reduction rate of the silicone layer at 380 DEG C, measured by thermogravimetry, is no more than than 9 mass%.

Description

Laminate

The present invention relates to a laminate having at least two resin layers, which is used for, for example, a mold release material, a buffer material, an anti-slip material, and the like, and which has a silicone layer and a polyimide layer.

In the past, among the silicones represented by silicone rubber or silicone resin, the kneadable type silicone rubber has been widely used for mold release materials, buffer materials, anti-skid materials, etc. because of its excellent heat resistance and electrical properties. . For example, in the manufacture of flexible circuit boards (FPC), all-solid-state batteries, semiconductors, etc., it is known to be used as a mold release material such as press molding, a buffer material, and the like. In addition, it is also sometimes used as a non-slip material for conveying a carrier in a reflow step or the like.

If silicone containing only a silicone layer, such as silicone rubber, is directly used as a release material for press molding, it will deform, resulting in poor mounting dimensional accuracy, or wrinkles, which may cause workability problems. question. Therefore, it has been known that silicone and a plastic film are combined and integrated to be used in the form of a laminate. At this time, as the plastic film, for example, as disclosed in Patent Document 1, a polyester resin film or the like is used. Moreover, in order to improve adhesiveness, silicone is laminated|stacked on a polyester resin film via an undercoat layer etc. in many cases. prior art literature Patent Literature

[Patent Document 1] Japanese Patent Laid-Open No. 11-20082

[Problems to be Solved by Invention]

In recent years, press molding in the fields of all-solid-state batteries and semiconductors tends to increase the molding temperature and molding pressure. For example, press molding may be performed at a temperature of about 100 to 300°C and a pressure of about 50 to 1000 MPa. . In addition, the use of a silicone film as a mold release material in the production process of FPC is also studied, but the production process of FPC also tends to increase the pressure molding temperature.

However, even if the silicone film (silicone layer) is integrated with other plastic films such as polyester film to form a laminate, the silicone film itself will become embrittled if it is repeatedly used by press molding in a high temperature environment. , unable to maintain the cushioning property, and there are abnormalities such as the inability to use it repeatedly for a long time.

In addition, when used as a carrier in the reflow step, in many cases, a silicone film is laminated on a metal plate and used, but from the viewpoint of weight reduction, it has also been studied to use a resin sheet instead. For the metal plate, for example, the above-mentioned laminate of the silicone film and the polyester film can be used. However, since the carrier is also heated to a high temperature during the reflow process, the silicone film may become embrittled, or the polyester film may undergo dimensional changes, etc., which make it difficult to use for a long time and put it into practical use.

Therefore, the subject of this invention is to provide the laminated body which has a silicone layer, even if it is used in a high temperature environment, the embrittlement of a silicone layer is suppressed, and it can be used for a long time. Moreover, the subject of this invention is to provide the laminated body which can suppress embrittlement even when used in a high temperature environment, can be used for a long period of time, and can be suitably used for a specific use. [Technical means to solve problems]

The inventors of the present invention have repeatedly conducted intensive research, and found that, by using a polyimide layer, or resin layers (A) and (B) having a tensile storage modulus that can be suitably used for a specific application, as the silicone layer The above-mentioned problems can be solved by using the integrated resin layer and the silicone layer or resin layer (A) whose weight loss rate is low even when heated at high temperature, and the following invention has been completed. That is, the present invention provides the following [1] to [16]. [1] A laminate comprising a silicone layer and a polyimide layer, and The weight reduction rate in 380 degreeC of the said silicone layer by thermogravimetry is 9 mass % or less. [2] The laminate according to the above [1], wherein a polyimide layer is provided on both surfaces of the silicone layer. [3] The laminate according to the above [1], wherein the polyimide layer is provided only on one side of the silicone layer, and a cover film is provided on the other side of the silicone layer. [4] The laminate according to any one of the above [1] to [3], wherein the silicone layer contains 0.1 to 10% by mass of titanium oxide. [5] The laminate according to any one of the above [1] to [4], wherein the tensile storage modulus of the polyimide layer at 23° C. is greater than the tensile storage modulus of the silicone layer at 23° C. Extended storage modulus. [6] The laminate according to any one of the above [1] to [5], wherein the tensile failure stress retention rate of the silicone layer after heat treatment at 300° C. for 3 hours is 10% or more. [7] The laminate according to any one of the above [1] to [6], wherein the tensile failure strain retention rate of the silicone layer after heat treatment at 300° C. for 3 hours is 10% or more. [8] The laminate according to any one of the above [1] to [7], wherein the silicone layer:polyimide layer has a thickness ratio of 99:1 to 20:80. [9] The laminate according to any one of the above [1] to [8], which is used as any one of a mold release material, a buffer material, and a slip-resistant material. [10] The layered product according to any one of the above [1] to [8], which is used for any one of press molding, vacuum molding, and air pressure molding. [11] The laminate according to any one of the above [1] to [8], which is used as a carrier film. [12] A laminate comprising a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (A) having a tensile storage modulus at 23°C of 1 GPa or more ( B), and The resin layer (A) has a weight reduction rate of 9 mass % or less at 380° C. by thermogravimetry, and the laminate is used as any one of a mold release material, a buffer material, and an anti-slip material. [13] A laminate comprising a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (A) having a tensile storage modulus at 23°C of 1 GPa or more ( B), and The resin layer (A) has a weight reduction rate of 9 mass % or less at 380° C. by thermogravimetry, and the laminate is used in any of press molding, vacuum molding, and air pressure molding. [14] A laminate comprising a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (A) having a tensile storage modulus at 23°C of 1 GPa or more ( B), and The weight reduction rate of the said resin layer (A) in 380 degreeC by thermogravimetry was 9 mass % or less, and the said laminated body was used as a carrier film. [15] A method of using the layered product according to any one of the above [1] to [8], wherein the layered product is used as a mold release material or a buffer material during molding. [16] A method of using the layered product according to any one of the above [3] to [8], wherein when the layered product is used as a mold release material or a buffer material during molding, the cover film is peeled off, and the polymer The imide layer side was arranged on the molding die side, and the silicone layer side was arranged on the molded body side. [Effect of invention]

According to the present invention, it is possible to provide a laminated body having a silicone layer, which can be used for a long period of time with suppressed embrittlement of the silicone layer even when used in a high-temperature environment. Moreover, according to this invention, even if it uses in a high temperature environment, it can provide the laminated body which can suppress embrittlement, can be used for a long time, and is suitable for a specific use.

Hereinafter, the present invention will be described in detail, but the present invention is not limited to the embodiments described below. Furthermore, in the present invention, when it is expressed as a "main component", unless otherwise specified, it includes the meaning that other components are allowed to be included within the range that does not interfere with the function of the main component. At this time, the content ratio of the main component is not specified, but the main component accounts for 50 mass % or more, preferably 60 mass % or more, more preferably 70 mass % or more, and still more preferably 80 mass % in the composition. More than 90% by mass (including 100%) is particularly preferred.

In the present invention, when it is expressed as "X to Y" (X and Y are arbitrary numbers), unless otherwise specified, the meanings of "more than X and less than Y" and "preferably greater than X" are included. and the meaning of "preferably less than Y". Furthermore, in the present invention, when expressed as "more than X" (X is an arbitrary number), unless otherwise specified, the meaning of "preferably greater than X" is included; when expressed as "less than Y" (Y is any number), unless otherwise specified, the meaning of "preferably less than Y" is included.

<Laminated body> The laminate system of the present invention includes a silicone layer and a polyimide layer. In the present invention, in addition to the silicone layer, the polyimide layer is provided, whereby wrinkles and bending are less likely to occur, thereby improving heat resistance. Therefore, for example, when it is used as a mold release material or a buffer material for press forming, vacuum forming, pressure forming, etc., the productivity of the formed body is improved. Moreover, when used as a carrier film for conveyance, for example, even if it is used in a high temperature environment, a workpiece can be conveyed appropriately. Furthermore, the laminated body can be repeatedly used for a long period of time in a high temperature environment.

[Silicone layer] The silicone layer of the present invention has a weight reduction rate of 9 mass % or less at 380° C. by thermogravimetry. If the weight reduction rate at 380°C exceeds 9% by mass, when the laminate is used in a high temperature environment, the silicone layer will become embrittled, and the cushioning properties and other properties cannot be maintained, and dimensional changes are likely to occur. For this reason, there is an abnormality such that the laminated body cannot be used repeatedly for a long period of time in a high temperature environment. From the viewpoint of suppressing embrittlement of the silicone layer in a high-temperature environment and enabling the laminate to be used for a longer period of time, the weight reduction rate at 380° C. is preferably 7% by mass or less, more preferably 6% by mass or less, and further Preferably it is 5 mass % or less. The lower the weight reduction rate at 380°C, the better, as long as it is 0% by mass or more. Considering the characteristics of the silicone forming the silicone layer, the weight reduction rate at 380°C is more than a fixed value, for example, 1 mass % or more. Furthermore, the weight loss rate at 380°C obtained by thermogravimetric measurement means that the sample collected from the silicone layer is heated at a fixed heating rate in the atmosphere, and the weight loss at 380°C is relative When the ratio to the initial weight is expressed as a percentage, the details can be measured by the method described in the examples.

The tensile failure stress retention rate of the silicone layer after heat treatment at 300° C. for 3 hours is preferably 10% or more, more preferably 20% or more, more preferably 30% or more, and more preferably 35%, particularly preferred It is more than 40%, and the best is more than 45%. When the tensile failure stress retention rate during high temperature heating is as high as described above, embrittlement of the silicone layer and the like when heated at high temperature for a long time can be suppressed, and the laminated body can be used for a long time. The tensile failure stress retention ratio is preferably as high as possible, and may be 100% or less, and usually about 70% or less.

In addition, the tensile failure strain retention rate of the silicone layer after heat treatment at 300° C. for 3 hours is preferably 10% or more, more preferably 30% or more, more preferably 40% or more, and still more preferably 50% or more. , the best is more than 60%, the best is more than 70%. If the tensile failure strain retention rate during high temperature heating is as high as described above, even after heating at high temperature for a long time, the cushioning properties of the silicone layer and the like are maintained, and the laminated body can be used for a long time. The above-mentioned tensile failure strain retention ratio is preferably as high as possible, as long as it is 100% or less, and is usually about 95% or less.

Furthermore, the tensile failure stress retention rate and the tensile failure strain retention ratio refer to the tensile test at the initial stage before heat treatment and after heat treatment at 300°C for 3 hours, respectively, to measure the tensile failure before and after heat treatment. Stress and elongation, and the ratio of the failure stress after heat treatment to the initial failure stress before heat treatment, and the ratio of the failure strain after heat treatment to the initial failure strain before heat treatment are expressed as percentages. In addition, the stretching direction only needs to be the flow direction (MD, Machine Direction) of the resin. When the MD is not clear, it can be stretched in the direction with the highest initial failure stress to measure the failure stress and failure strain. . In addition, the measurement can be carried out on a test piece cut out from the silicone layer of the laminated body, and when it is difficult to cut out the test piece, it can also be carried out on a test piece produced by the same method as the molding method of the silicone layer in the laminated body. The sample (thickness is also the same as that of the silicone layer of the laminate) was measured. About the tensile storage modulus etc. mentioned later, it can also measure similarly.

The initial failure stress of the silicone layer is not particularly limited, but is preferably 3 MPa or more, more preferably 5 MPa or more, and more preferably 8 MPa or more, and, for example, 25 MPa or less, preferably 20 MPa or less, and more Preferably it is 15 MPa or less. Also, the initial failure strain of the silicone layer is not particularly limited, but is preferably 200% or more, more preferably 250% or more, further preferably 300% or more, particularly preferably 350% or more, and, for example, 1400% or less , preferably below 1300%. Since the initial failure stress and the initial failure strain of the silicone layer are more than a fixed value, good cushioning properties can be ensured, and the mechanical strength is also excellent.

The silicone layer of the present invention is a layer containing silicone as a main component. As the silicone, a silicone containing a siloxane skeleton represented by the following formula (1) is preferable. In addition to the polydimethylsiloxane in which all R in the following formula (1) are methyl groups, a part of methyl groups can be appropriately selected (for example, about 30 mol % or less, preferably 20 mol %) % or less) are substituted with one or two or more of other alkyl groups, vinyl groups, phenyl groups, fluoroalkyl groups, etc. to obtain various polydimethylsiloxanes. In addition, n in the formula is a positive integer of 1 or more, preferably 3 to 5000.

[hua 1]

The above-mentioned silicone is preferably a silicone elastomer resin. Therefore, the silicone layer preferably contains a silicone elastomer resin, and more preferably contains a silicone elastomer resin as a main component. As an example of the silicone elastomer resin, a silicone elastomer resin containing polydimethylsiloxane as a main component can be preferably exemplified.

The above-mentioned silicone elastomer resin, especially polydimethylsiloxane, also preferably contains a vinyl group. By containing vinyl, the compression set becomes smaller, and the thickness tends to be less likely to change even if it is used repeatedly during press molding, so that sufficient cushioning properties tend to be maintained, resulting in excellent durability. . In the case of containing vinyl, the content of vinyl is preferably 0.05-5 mol %, more preferably 0.5-4 mol %, and more preferably 1-3 mol % relative to the total amount of the silicone elastomer resin. Ear%. If the content of the vinyl group is above the above lower limit value, the crosslinking density of the silicone elastomer resin tends to be easily adjusted, and the silicone elastomer resin having the desired compression set tends to be easily obtained. On the other hand, it is preferable that it is below the said upper limit since the silicone elastomer resin will not be crosslinked excessively.

In addition, from the viewpoint of adjusting the crosslinking point, the silicone elastomer resin may contain a vinyl-free silicone elastomer resin, and a vinyl-containing silicone elastomer resin and a vinyl-free resin may be used in combination. Silicone elastomer resin.

The silicone elastomer resin is preferably of a kneadable type. The kneadable silicone elastomer resin is a non-liquid (for example, solid or paste) that does not have self-fluidity at room temperature (25°C) in an uncrosslinked state, but can be used in a kneader, etc. It can be mixed with other components, and can be uniformly mixed with additives and the like described later. Moreover, by making the silicone elastomer resin into a kneadable type, the productivity becomes good.

Moreover, in the silicone layer, the silicone elastomer resin is preferably cross-linked. By cross-linking the silicone elastomer layer, it is easy to impart cushioning properties and the like, and the compression set and the like are improved, so that it can be suitably used as a mold release material, a cushioning material, and the like during press molding. In addition, as will be described later, the silicone layer is more preferably a radiation-crosslinked body obtained by radiation-crosslinking.

The silicone layer of the present invention preferably contains a metal oxide. By containing the metal oxide in the silicone layer, the heat resistance is improved, and the above-mentioned weight loss rate at 380° C. is reduced. In addition, the retention rate of tensile stress at failure and the retention rate of tensile failure strain after the above-mentioned heat treatment can be improved. As metal oxides, titanium oxide, iron oxide, cerium oxide, etc. are mentioned, among them, titanium oxide and iron oxide are preferable. In addition, from the viewpoint of maintaining a high tensile fracture strain retention rate, iron oxide is more preferred, and titanium oxide is more preferred from the viewpoint of appearance properties such as coloring. A metal oxide may be used individually by 1 type, and may use 2 or more types together.

The content of the metal oxide in the silicone layer is preferably 0.1 to 10 mass %, more preferably 0.3 to 7 mass %, further preferably 0.5 to 5 mass %, and particularly preferably 0.7 to 3 mass %. By setting it as the said lower limit or more, heat resistance can be improved suitably, and the said weight reduction rate in 380 degreeC can be made low enough. On the other hand, by setting it below an upper limit, heat resistance can be improved, without impairing the performance, such as the cushioning property of a silicone layer.

Furthermore, the silicone layer of the present invention also preferably contains carbon black. Since the heat resistance of the silicone layer is improved by containing carbon black, the above-mentioned weight reduction rate at 380°C is reduced. In addition, the retention rate of tensile stress at failure and the retention rate of tensile failure strain after the above-mentioned heat treatment can be improved. Moreover, flame resistance can also be improved. As carbon black, graphitized carbon, furnace black, acetylene black, Ketjen black, etc. are mentioned, Among them, furnace black is preferable from a viewpoint of availability and price. One type of carbon black may be used alone, or two or more types may be used in combination.

The content of carbon black in the silicone layer is preferably 0.05 to 10 mass %, more preferably 0.1 to 5 mass %, further preferably 0.2 to 3 mass %, and particularly preferably 0.3 to 2 mass %. By setting it as the said lower limit or more, heat resistance can be improved suitably, and the said weight reduction rate in 380 degreeC can be made low enough. On the other hand, by setting it below the upper limit, heat resistance and flame resistance can be improved without impairing performance such as cushioning properties of the silicone layer.

In addition to reinforcing fillers such as fumed silica, precipitated silica, diatomaceous earth, and quartz powder, various processing aids, heat resistance improvers, etc., the silicone layer may also contain the elastomer having Various functional additives. These may be used alone or in combination of two or more. As an additive, a flame retardance imparting agent, a heat-dissipating filler, a conductive filler etc. are mentioned, for example.

The A-type durometer hardness of the silicone layer is preferably 3 or higher, more preferably 5 or higher, further preferably 15 or higher, particularly preferably 25 or higher, particularly preferably 35 or higher, and most preferably 45 or higher. Moreover, the A-type durometer hardness is preferably 90 or less, more preferably 80 or less, still more preferably 70 or less, and particularly preferably 60 or less. By making the A-type durometer hardness more than the above lower limit value, the thickness of the silicone molded body tends not to change easily even if it is used repeatedly during press molding, so that sufficient cushioning properties are maintained. Makes durability excellent. In addition, the tackiness of the surface of the silicone molded body is moderately suppressed, and the handleability tends to be easily improved. On the other hand, by setting the A-type durometer hardness to be equal to or less than the above-mentioned upper limit value, the followability and adhesiveness to a pressurized product during press molding and the like tend to be easily improved. In addition, the A-type durometer hardness can be measured according to JIS K6253-3:2012. As a method of adjusting the hardness of the A-type durometer, for example, the following methods can be mentioned: a method of adjusting the filling amount of a filler such as silica prepared as a filler in the silicone layer; a method of appropriately selecting the raw material silicone types of methods, etc. In addition, from the viewpoints of the followability to the molded body during press molding, the adhesiveness, and the surface contact adhesion of the silicone layer, for example, the tensile storage modulus of the silicone layer at 23°C is, for example, 100 MPa or less, preferably 70 MPa or less, more preferably 50 MPa or less, still more preferably 30 MPa or less, and particularly preferably 10 MPa or less. In addition, the tensile storage modulus of the silicone layer at 23° C. is preferably 0.1 MPa or more, more preferably 0.5 MPa or more, and still more preferably 1 MPa or more.

As the silicone elastomer resin, a commercially available silicone elastomer resin containing a metal oxide as a heat resistance improver can also be used. As a commercial item, "X-30-3888-U" manufactured by Shin-Etsu Chemical Industry Co., Ltd. contains about 1 to 3 mass % of iron oxide as a metal oxide, and about 1 to 10 mass % of titanium oxide is included. "TSE2323-5U" manufactured by Momentive Advanced Materials Co., Ltd., which is a metal oxide, and "TSE2323-7U" manufactured by Momentive Advanced Materials Co., Ltd., which contains about 0.1 to 1% by mass of titanium oxide as a metal oxide.

The thickness of the silicone layer may be appropriately selected according to the application, and is preferably 3 mm or less, more preferably 1 mm or less, further preferably 800 μm or less, particularly preferably 600 μm or less, and particularly preferably 400 μm or less. . Furthermore, from the viewpoint of moderate elasticity, long-term use, and repeated use, the lower limit of the thickness of the silicone layer is preferably 10 μm, more preferably 20 μm, further preferably 30 μm, and particularly preferably 50 μm .

[Polyimide layer] The polyimide layer of the present invention contains polyimide as a main component. The temperature at which the weight of the polyimide layer of the present invention is reduced by 2% by thermogravimetric measurement is preferably 260° C. or higher. By making this temperature 260 degreeC or more, the heat resistance of a polyimide layer is improved, and by using together with the said silicone layer, the heat resistance of a laminated body is further improved. Therefore, the laminated body can be repeatedly used for a long period of time without deteriorating the performance of the laminated body in various applications used in a high temperature environment. From the viewpoints of heat resistance, durability, etc., the temperature at which the weight decreases by 2% by thermogravimetric measurement is more preferably 275°C or higher, more preferably 350°C or higher, still more preferably 400°C or higher, and still more It is preferably 450°C or higher, particularly preferably 500°C or higher, and most preferably 540°C or higher. The temperature at which the weight of the polyimide layer decreases by 2% by thermogravimetric measurement is not particularly limited, and it may be, for example, 750°C or lower, or 700°C or lower. The temperature at which the weight is reduced by 2% obtained by thermogravimetric measurement refers to the temperature at which the weight of the sample collected from the polyimide layer is heated in the atmosphere, and the weight is reduced by 2% relative to the initial weight. Details are available at The measurement was carried out by the method described in the examples.

The tensile storage modulus of the polyimide layer of the present invention at 300° C. is preferably 2 GPa or more. If the tensile storage modulus at 300° C. is 2 GPa or more, even if pressure is applied to the layered body by press molding or the like at a high temperature, dimensional changes such as stretching of the layered body in the plane direction are suppressed. Therefore, even if strain occurs between the silicone layer and the silicone layer, it does not peel off, and it is easier to use the laminate repeatedly in a high temperature environment. The tensile storage modulus at 300°C is preferably 2.3 GPa or more, more preferably 2.6 GPa or more, and more preferably 3 GPa or more, from the viewpoint of reducing dimensional changes even when pressure is applied in a high temperature environment , 3.5 GPa or more is particularly preferred. The upper limit of the above-mentioned tensile storage modulus at 300° C. is not limited. For example, as long as it is 10 GPa or less, it may be 7 GPa or less, or 6 GPa or less.

The tensile storage modulus of the polyimide layer at 23°C is preferably greater than the tensile storage modulus of the silicone layer at 23°C. In addition, the tensile storage modulus of the polyimide layer at 23° C. is preferably 3.7 GPa or more. When the tensile storage modulus of the polyimide layer at room temperature is high as described above, the handleability becomes good, for example, it is easy to install in a molded body at the time of molding. Moreover, when a laminated body is manufactured by a lamination method etc., even if it is thin, tension|tensile_strength is easy to act, and manufacture becomes easy, and the obtained laminated body is also less likely to generate|occur|produce a wrinkle etc.. From the viewpoints of workability and ease of manufacture, the tensile storage modulus at 23° C. is preferably 4 GPa or more, more preferably 4.5 GPa or more, still more preferably 5 GPa or more, and particularly preferably 6 GPa or more , the best is above 7 GPa. The upper limit of the tensile storage modulus at 23° C. is not limited, for example, as long as it is 15 GPa or less, it may be 13 GPa or less, or 11 GPa or less. Furthermore, regarding the tensile storage modulus of the polyimide layer at 23° C. and 300° C., it is sufficient to measure the tensile storage modulus of the polyimide layer monolayer using a viscoelasticity spectrometer. The tensile storage modulus of the silicone layer at 23°C can also be determined by using a viscoelasticity spectrometer on the single layer of the silicone layer. In addition, the tensile storage modulus only needs to be the value measured in the flow direction (MD: Machine Direction) of the resin. When the MD is not clear, the value in the direction with the highest tensile storage modulus is used Can.

The linear expansion coefficient of the polyimide layer is preferably 33×10 ^-6 /°C or less. By making the linear expansion coefficient of the polyimide layer 33×10 ^-6 /°C or less, even after changing the temperature from a low temperature to a high temperature and using it repeatedly, the dimensional change is small and the dimensional stability is improved. Therefore, it can be suitably used for various applications used in a high temperature environment. The linear expansion coefficient of the polyimide layer is preferably 27×10 ^-6 /°C or lower, more preferably 22×10 ^-6 /°C or lower, still more preferably 18×10 ^-6 /°C or lower, particularly preferably 14×10 ^-6 /°C or less. The linear expansion coefficient of the polyimide layer is not particularly limited, but may be, for example, 5×10 ⁻⁶ /°C or higher, or 8×10 ⁻⁶ /°C or higher.

The arithmetic mean roughness (Ra) of the outermost surface of the laminate including the polyimide layer is preferably 26 nm or less. For example, in the process of press molding, the polyimide layer will come into contact with the molding die side such as the press plate, and if the above-mentioned arithmetic mean roughness (Ra) is 26 nm or less, it will not be easy to face each other when the initial pressure is applied, etc. The forming mold such as a pressure plate is displaced, and the moldability becomes good when used as a mold release material, a buffer material, or the like. In addition, as will be described later, in the case where polyimide layers are provided on both sides of the silicone layer, and the two outermost surfaces of the laminate are polyimide layers, the arithmetic mean of the two outermost surfaces is preferred. The roughness (Ra) was all 26 nm or less. When the two outermost surfaces of the layered body are polyimide layers, for example, one outermost surface is in contact with a molding die such as a pressure plate, and the other outermost surface is in contact with the molded body. Therefore, if the arithmetic mean roughness of the two outermost surfaces is small, it is not easy to shift not only with respect to a molding die such as a pressure plate, but also with respect to a molded body. When used as a mold release material, a buffer material, etc. The formability is further improved. The arithmetic mean roughness (Ra) is more preferably 20 nm or less, more preferably 17 nm or less, and still more preferably 13 nm, from the viewpoint of preventing displacement with respect to a molding die such as a molded body or a pressure plate. Hereinafter, it is particularly preferably 10 nm or less. In addition, the lower limit of the arithmetic mean roughness (Ra) is not particularly limited, and is, for example, 0.5 nm, preferably 1 nm, more preferably 1.5 nm, and still more preferably 2 nm. When the arithmetic mean roughness is 0.5 nm or more, when the laminates of the present invention are stacked on each other, the convex portions come into point contact, thereby suppressing adhesion of the laminates, and easily obtaining a laminate excellent in releasability. Moreover, there exists a tendency for the rationality to become excellent also in the case where a laminated body is taken out one by one. In addition, when a molding die such as a pressure plate is opened to take out a molded body after pressure molding, the problem that the layered body adheres to the molding die such as a pressure plate is also improved, and the productivity tends to improve. Furthermore, when the two outermost surfaces of the layered body are polyimide layers, there are advantages in that the contact state between the layered body and the molded body can be appropriately made good, and positional alignment on the molded body can be easily performed. . It should be noted that the surface roughness (Ra) is measured by a three-dimensional non-contact surface shape measuring instrument, and may be measured according to the measurement conditions described in the examples.

The adjustment method of the arithmetic mean roughness is not particularly limited, and preferably, the following method can be mentioned: The surface roughness of mirror-polished metal rolls, endless metal belts, polymer films, etc. is appropriately adjusted.

The polyimide contained in the polyimide layer of the present invention may be obtained by polymerizing tetracarboxylic acid or tetracarboxylic dianhydride and diamine, and aromatic polyimide is preferably used. Specifically, those obtained by polymerizing an aromatic tetracarboxylic acid or an aromatic tetracarboxylic dianhydride, and an aromatic diamine and/or an aliphatic diamine may, for example, be mentioned. In addition, the aliphatic diamine includes an alicyclic diamine.

(再者，式(2)中，R ¹為含有芳香環之4價有機基，R ²為含有芳香環之2價有機基，m為1以上之整數)。 As the polyimide contained in the polyimide layer of the present invention, for example, a polyimide represented by the following general formula (2) is used. [hua 2]

(In addition, in formula (2), R ¹ is a tetravalent organic group containing an aromatic ring, R ² is a divalent organic group containing an aromatic ring, and m is an integer of 1 or more).

As long as the tetravalent organic group of R ¹ has an aromatic ring, for example, an organic group having 6 to 24 carbon atoms, preferably 6 to 18 carbon atoms, and more preferably 6 to 12 carbon atoms may be mentioned. As R ¹ , an aromatic tetracarboxylic acid residue may be mentioned, and specifically, the following formulae (3-1) to (3-5) may be mentioned.

[hua 3]

Among the above, it is preferably any one of the formulae (3-1) and (3-2), and among them, it is preferably any one of the following (3-1') and (3-2') The represented organic group is more preferably the organic group represented by the following (3-1'). [hua 4]

In the polyimide represented by the general formula (2), the content ratio of the organic group represented by any one of the above (3-1') and (3-2') in R ¹ is, for example, 50 moles. % or more, preferably more than 70 mol%, more preferably more than 90 mol%, and most preferably 100 mol%.

As long as the divalent organic group of R ² has an aromatic ring, for example, an organic group having 6 to 24 carbon atoms, preferably 6 to 18 carbon atoms, and more preferably 6 to 15 carbon atoms may be mentioned. The divalent organic group of R ² is preferably an organic group represented by any one of the following formula (4) and formula (5).

(再者，式(4)中，R ³及R ⁴分別獨立地為氫原子、甲基、及鹵素原子中之任一者；式(5)中，X所表示之基係單鍵、氧原子、硫原子、C=O、-CH ₂-、-CH(CH ₃)-、-C(CH ₃) ₂-、-SO ₂-、及-C(CF ₃) ₂-中之任一者；R ⁵、R ⁶、R ⁷、及R ⁸分別獨立地為氫原子、甲基、及鹵素原子中之任一者)。 [hua 5]

(Further, in formula (4), R ³ and R ⁴ are each independently any one of a hydrogen atom, a methyl group, and a halogen atom; in formula (5), the group represented by X is a single bond, oxygen atom, sulfur atom, any one of C=O, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -SO ₂ -, and -C(CF ₃ ) ₂ - ; R ⁵ , R ⁶ , R ⁷ , and R ⁸ are each independently any one of a hydrogen atom, a methyl group, and a halogen atom).

In the polyimide represented by the general formula (2), at least a part of R ² is preferably an organic group represented by the formula (4). In the polyimide represented by the above general formula (2), by making at least a part of R ² an organic group represented by the formula (4), the heat resistance is increased, and the weight is reduced by 2%. temperature becomes higher. In addition, the tensile storage modulus at 300° C. is increased, and the linear expansion coefficient of the polyimide layer is easily lowered. In the formula (2), from the viewpoint of heat resistance and low coefficient of linear expansion, the bonding positions in the above formula (4) are preferably 1 and 4 positions, and both R ³ and R ⁴ are preferably hydrogen. atom. Therefore, at least a part of R ² in the formula (2) is more preferably an organic group represented by the following formula (4-1). [hua 6]

In the polyimide represented by the general formula (2), the content ratio of the organic group represented by the above formula (4-1) in R ² is, for example, 10 mol % or more, preferably 30 mol % or more , more preferably 50 mol% or more, and may contain 70 mol% or more, and may also contain 100 mol%.

In the formula (2), at least a part of R ² is an organic group represented by the above formula (4) (preferably the formula (4-1)), and a part of R ² may be a group other than the above formula (4). Organic group of aromatic ring. R ² other than the above formula (4) may, for example, be a divalent organic group having 12 to 24 carbon atoms, preferably 12 to 18 carbon atoms, and more preferably 12 to 15 carbon atoms. Specifically, the organic group represented by the above formula (5) is preferable.

In formula (5), X is preferably an oxygen atom, and each of R ⁵ , R ⁶ , R ⁷ , and R ⁸ is preferably a hydrogen atom. In addition, the bonding position in the formula (5) is preferably 4 and 4' positions. Therefore, the organic group represented by the formula (5) is more preferably an organic group represented by the following formula (5-1). In addition, in a preferred form of the compound of the formula (2), at least a part of R ² is an organic group represented by the above formula (4) (preferably the formula (4-1)), and the rest is the following formula (5) The organic group represented by -1).

[hua 7]

The polyimide is preferably a polyimide obtained by polymerizing 3,3',4,4'-biphenyltetracarboxylic acid or its acid dianhydride and 1,4-phenylenediamine, specifically, The polyimide represented by the following formula (6) is preferable. By using the polyimide represented by the following formula (6), the heat resistance becomes good, and the temperature at which the weight of the polyimide layer is reduced by 2% becomes high. In addition, it is easy to obtain a polyimide layer with a low linear expansion coefficient and a high tensile storage modulus at 300°C. A commercially available product can also be used for the polyimide represented by the formula (6). Specifically, "Upilex-S" manufactured by Ube Industries, Ltd. can be mentioned.

再者，式(6)中m係與上述相同。 [hua 8]

In addition, m in Formula (6) is the same as above.

In addition, the polyimide is also preferably a polyimide obtained by copolymerizing pyromellitic acid or its acid dianhydride, p-phenylenediamine, and 4,4'-diaminodiphenyl ether, specifically , preferably the following copolymer polyimide, that is, in the above formula (2), R ¹ is an organic group of formula (3-2'), and a part of R ² is an organic group of formula (4-1), and the rest is an organic group of formula (5-1). With regard to the copolymer polyimide, by controlling the combination of monomers (sequential control), a polyimide having a low coefficient of linear expansion and relatively good heat resistance and the like can be obtained. Specifically, by reacting 4,4'-diaminodiphenyl ether with pyromellitic dianhydride in advance, and then adding p-phenylenediamine, a low coefficient of linear expansion and high heat resistance can be obtained. Polyimide with excellent properties. Therefore, the tensile storage modulus of the polyimide layer at 300° C. and the temperature at which the weight is reduced by 2% are also easily increased. As this copolymer polyimide, a commercial item can also be used, for example, "Apical NPI" manufactured by Kaneka Corporation is mentioned.

In addition, in the polyimide, at least a part of R ² need not be an organic group represented by the above formula (4), and R ² may be a polyimide containing the above formula (5), preferably the above formula (5-1) imine, in this case, R ¹ is more preferably the formula (3-2'). As such a polyimide, a commercial item may be sufficient, and "Apical AH" by Kaneka Corporation, "Kapton" by Toray DuPont Corporation, etc. are mentioned specifically,.

In addition to polyimide, the polyimide layer of the present invention can also be appropriately formulated with other resins, fillers, and various additives, such as heat stabilizers, ultraviolet absorbers, Light stabilizers, nucleating agents, colorants, lubricants, flame retardants, etc. The content of other resins is not particularly limited, but it may be, for example, about 50 parts by mass or less, 30 parts by mass or less, or 10 parts by mass or less, relative to 100 parts by mass of the polyimide. The resin in the layer preferably contains polyimide.

The thickness of the polyimide layer may be appropriately selected according to the application, and the thickness of the polyimide layer should be appropriately selected for imparting the required heat resistance and dimensional stability to the laminate without impairing the cushioning properties or the like imparted by the silicone layer. From a viewpoint, the thickness of the polyimide layer is preferably 150 μm or less, more preferably 130 μm or less, further preferably 100 μm or less, particularly preferably 80 μm or less, particularly preferably 60 μm or less, and more preferably It is preferably 3 μm or more, more preferably 5 μm or more, still more preferably 10 μm or more, and particularly preferably 15 μm or more. Furthermore, when the polyimide layers are provided on both sides of the silicone layer, the thickness of the polyimide layers refers to the thicknesses of the polyimide layers respectively provided on both sides of the silicone layer.

Furthermore, in the laminate of the present invention, the thickness of the silicone layer:polyimide layer is preferably 99:1 to 20:80. The layered body can be suitably used as a mold release material and a buffer material by making the thickness ratio within the above-mentioned range, so that the heat resistance becomes favorable and moderate elasticity is obtained. From these viewpoints, the thickness ratio is more preferably 95:5 to 30:70, more preferably 90:10 to 40:60, and particularly preferably 85:15 to 50:50. Furthermore, the thickness of the polyimide layer here refers to the thickness of the polyimide layer provided on one side of the silicone layer, when the polyimide layer is provided on both sides of the silicone layer. , the thickness of each polyimide layer respectively disposed on both sides of the silicone layer can be within the above range.

[Laminated structure] The laminate of the present invention may include a polyimide layer and a silicone layer, or may have a laminate structure in which the polyimide layer is provided only on one side of the silicone layer. That is, the laminated body of this invention may have the laminated structure of a polyimide layer/silicone layer. In the laminated structure, the polyimide layer may constitute one outermost surface of the laminated body, and the silicone layer may constitute the other outermost surface. More specifically, the layered product may have two types of two-layer structures, or may have a structure in which an undercoat layer described later is provided between the polyimide layer and the silicone layer in addition to the two types of two-layer structures. In the above layered structure, when the layered body is used as a mold release material or a buffer material when molding by press molding or the like, the polyimide layer side can be placed on the molding die side such as a press plate and the like. The silicone layer side is arranged on the molded body side. With such an arrangement, the laminated body is less likely to be displaced with respect to the molding die by the polyimide layer, and on the other hand, the releasability from the molded body is improved by the silicone layer.

Moreover, the laminated body of this invention may have the laminated structure which provided the polyimide layer on both surfaces of the silicone layer. That is, the laminate of the present invention may have a laminate structure of polyimide layer/silicone layer/polyimide layer. In this laminate structure, the polyimide layers may constitute the two outermost surfaces of the laminate. More specifically, the layered product may have a two-type three-layer structure, or in addition to the two-type three-layer structure, either or both of the polyimide layer and the silicone layer may have a primer to be described later. layer structure. According to such a layered structure, when the layered body is used as a mold release material or a buffer material during molding by press molding or the like, the layered body is less likely to deviate from the molding die and the molded body due to the polyimide layer. It is easy to obtain a formed body with high surface smoothness. In addition, low molecular weight siloxane components such as low molecular weight cyclic siloxane may be precipitated in the silicone layer due to heating, and these components may adhere to the molding die or the obtained molded body and cause contamination. The provision of a polyimide layer can prevent the precipitation of low molecular weight siloxane components and inhibit the pollution caused by low molecular weight siloxane components. Also, when the silicone film is used as a mold release material or a buffer material, a heat treatment or the like may be performed to remove the low molecular weight siloxane component adhering to the molding mold, but by providing polyimide layers on both sides , can also reduce the frequency of heat treatment.

As a method of suppressing contamination of the molded body caused by the precipitation of the low-molecular-weight siloxane component as described above, and as a method to easily obtain a molded body with high surface smoothness, the following method can be adopted. In a laminate having a polyimide layer, the silicone layer side is placed on the molding die side such as a pressure plate, and the polyimide layer side is placed on the molded body side.

(undercoat) In addition, in each laminated structure, the polyimide layer may be directly laminated on the silicone layer, or may be laminated through an undercoat layer. From the viewpoint of securing the adhesiveness to the silicone layer, the primer layer preferably contains a silicone resin, and more preferably contains a silicone resin as a main component. Examples of silicone resins that can be used for the undercoat layer include addition type silicone resins, condensation type silicone resins, UV (Ultraviolet, ultraviolet) curing type silicone resins, and the like. Among them, addition type silicone resins are preferred. Molded silicone resin. These may be used alone or in combination of two or more.

As the addition type silicone resin, the following resins can be exemplified, that is, the polydimethylsiloxane containing vinyl group is used as the base polymer, and the polymethylhydrosiloxane is formulated as the cross-linking agent. In the presence of platinum catalyst It is obtained by reaction hardening under the following conditions. As the condensed silicone resin, the following resin can be exemplified, that is, a polydimethylsiloxane containing a silanol group at the end is used as a base polymer, and polymethylhydrosiloxane is prepared as a cross-linking agent, and is prepared in an organic tin contact Obtained by heating and hardening in the presence of a medium. Examples of UV-curable silicone resins include resins using polydimethylsiloxane containing acryl group or methacryloyl group as a base polymer, polydimethylsiloxane containing mercapto group and vinyl group as base polymer Photopolymerization formulated in methylsiloxane as base polymer, above-mentioned addition type silicone resin, or epoxy group-containing polydimethylsiloxane hardened by cationic hardening mechanism as base polymer, etc. Starter and hardened by irradiation with UV light. In addition, the undercoat layer may suitably contain a silane coupling agent, an adhesion improving agent, etc. as needed.

As a silane coupling agent, the compound represented by general formula ZSiX ₃ is mentioned, for example. Furthermore, in the above general formula, Z is an organic group with a carbon number of about 1 to 20 having functional groups such as vinyl, epoxy, amine, and mercapto groups, and X is a hydrolyzable functional group such as methoxy and ethoxy. or alkyl. In addition, the silane coupling agent is preferably a compound represented by the general formula YRSiX ₃ , and preferably Y is a functional group such as a vinyl group, an epoxy group, an amino group, a mercapto group, etc., and R is a methylene group, an ethylidene group, a propylene group is an alkyl group, and X is a hydrolyzable functional group such as a methoxy group or an ethoxy group, or an alkyl group.

Examples of the silane coupling agent include vinyltriethoxysilane, vinyltrimethoxysilane, γ-glycidylpropyltrimethoxysilane, γ-glycidylpropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane Silane etc. These may be used alone or in combination of two or more.

As an adhesion improving agent, the siloxane which has an epoxy group at a molecular chain terminal or a side chain is mentioned preferably.

The thickness of the undercoat layer is preferably 0.01 to 1 μm, more preferably 0.03 to 0.7 μm, and still more preferably 0.05 to 0.5 μm. As long as the thickness is equal to or more than the above lower limit value, there is a tendency that a cured coating having a uniform thickness can be obtained, and sufficient adhesive force with the silicone layer can be obtained. Moreover, in general, the film strength of the silicone resin constituting the primer layer is not particularly large, but as long as the thickness is below the above upper limit value, cohesion failure of the primer layer is suppressed, and the strength of the laminate is easily increased.

(cover film) When the laminate system of the present invention has a laminate structure in which a polyimide layer is provided only on one side of the silicone layer, a cover film can also be installed on the surface of the silicone layer without the polyimide layer. The cover film may include a resin film other than the polyimide layer and the silicone layer. The material of the cover film is not particularly limited, and examples thereof include polyolefin-based resins, styrene-based resins, polyester resins, polycarbonate-based resins, polyamide-based resins, polyphenylene sulfide resins, and polyphenylene sulfide resins. Ether resin, polyaryl ether ketone resin, liquid crystal polymer resin, etc. Among them, from the viewpoint of heat resistance or mechanical strength, it is preferable to contain a polyester resin as a main component, and it is more preferable to contain a polyester resin as a main component.

Among the polyester resins, it is preferable to use a crystalline polyester resin, and examples of the crystalline polyester resin include polyethylene terephthalate, polyethylene naphthalate, and the like. Among them, polyethylene terephthalate is preferred from the viewpoints of heat resistance, film plasticity, smoothness, and commercial availability. These may be used alone or in combination of two or more.

In addition, the cover film may contain additives such as ultraviolet absorbers, light stabilizers, antioxidants, plasticizers, nucleating agents, lubricants, pigments, and dyes within a range that does not impair the effects of the present invention. From the viewpoint of mechanical strength, at least uniaxial extension is preferable, and biaxial extension is more preferable. The cover film can be an engineering film used to form a silicone layer during the manufacturing process, or a protective film to protect the silicone layer during transportation, storage, and the like. The cover film can be removed from the laminate before the laminate is used as a mold release material, a buffer material, a non-slip material, a carrier film, or the like.

The thickness of the cover film is not particularly limited, but is preferably 10 to 350 μm, more preferably 15 to 300 μm, and still more preferably 20 to 250 μm.

<Manufacturing method of laminated body> The method for producing the layered product of the present invention is not particularly limited as long as the polyimide layer can be layered on at least one side of the silicone layer, and a known method can be used for the layering method.

For example, a polyimide layer can be made, and a silicone layer can be made separately, and these layers can be laminated; a polyimide layer can also be made, and the silicone layers can be made on the polyimide layer at the same time. The silicone layer can be made in reverse, and the polyimide layer is made on the silicone layer and the layers are laminated simultaneously; the polyimide layer and the silicone layer can also be made while the polyimide layer and the silicone layer are made. In addition, when the polyimide layer is provided on one side of the silicone layer, a cover film can be appropriately laminated on the surface of the silicone layer on which the polyimide layer is not provided.

Regarding the polyimide layer and the silicone layer, it is preferable to crosslink the silicone layer after laminating the silicone layer in an uncrosslinked state to form a laminate. If the silicone layer is cross-linked after the silicone layer and the polyimide layer are laminated, the polyimide layer can be laminated and integrated with the silicone layer with a higher bonding strength.

The polyimide layer and the silicone layer can be laminated by a co-extrusion method, a lamination method, or the like. In the co-extrusion method, the polyimide layer and the silicone layer can be kneaded and co-extruded at the same time by means of a feeding module method or a multi-manifold method to perform lamination. Moreover, as a lamination method, the method of laminating|stacking these after separately producing a polyimide layer and a silicone layer to obtain a polyimide layer and a silicone layer can be mentioned. In addition, it is also possible to perform lamination while forming a silicone layer on a prefabricated polyimide layer.

In addition, as described above, a primer layer may be provided between the polyimide layer and the silicone layer. In this case, a primer layer may be applied on the polyimide layer, and the primer layer may be appropriately applied to the primer layer. It is dried and hardened to form an undercoat layer. Then, a silicone layer may be laminated on the polyimide layer on which the undercoat layer is formed. The primer contains a base polymer for forming an undercoat layer, and a crosslinking agent, a photopolymerization initiator, a catalyst, a silane coupling agent, an adhesion improver, etc., which are formulated as necessary, and can be diluted with a solvent. Surface treatments such as corona treatment can also be performed on the primer coating surface of the silicone layer and/or the polyimide layer to improve the leveling or adhesion of the primer. Moreover, although it does not specifically limit about a primer, For example, it can harden by heating at the temperature of about 50-150 degreeC.

The laminate of the present invention is preferably produced by a lamination method. The lamination method is to put silicone, preferably a silicone elastomer resin, which has been mixed with metal oxides, other additives, etc. as necessary in a kneader or the like, in a preferably uncross-linked state, into two layers. The direction is successively sent out to a pair of polyimide films, which are respectively a polyimide layer, or between the polyimide film and the cover film. Here, silicone can be injected|thrown-in between films by extruding from a T-die etc. using an extruder etc., for example. Then, the thickness is adjusted by the gap of a roll as needed, and the laminated body which formed the silicone layer between the films, preferably the silicone layer of the uncrosslinked state, is obtained. However, in this case, the cover film may be appropriately omitted.

In addition, the silicone in an uncrosslinked state can be crosslinked, but as described above, it is preferable to perform crosslinking after laminating the silicone layer and the polyimide layer. As a cross-linking method, a method of adding a cross-linking agent or the like to silicone in advance, and cross-linking by light such as heat, ultraviolet rays, moisture in the air, etc., and cross-linking by irradiation of radiation can be exemplified. method.

Among them, the silicone layer is preferably cross-linked by irradiation with radiation. Crosslinking by irradiation is preferable because there is no concern that heat resistance is impaired by residues of the crosslinking agent, etc., and wrinkles and the like do not occur during crosslinking as in crosslinking by heating. Moreover, it is also preferable for ensuring the adhesiveness of a silicone layer and a polyimide layer. As a radiation, an electron beam, X-ray, a gamma ray etc. are mentioned, for example. These radiations are widely used industrially, and are easily available and energy efficient methods. Among them, the use of gamma rays is preferable from the viewpoint of having almost no absorption loss and high penetrability.

The irradiation amount of gamma rays can be appropriately selected and determined according to the type of resin, the amount of cross-linking groups, and the type of radiation source. For example, the irradiation dose of γ-rays is preferably 20 to 150 kGy, more preferably 30 to 120 kGy, further preferably 40 to 110 kGy, and particularly preferably 50 to 100 kGy. As long as the irradiation amount is equal to or more than the above lower limit value, the silicone layer can be sufficiently cross-linked, and as a result, the desired compression set or durometer hardness tends to be easily obtained. On the other hand, as long as the irradiation amount is equal to or less than the above upper limit value, the decomposition reaction does not occur, and the increase in the low molecular weight siloxane component can be suppressed.

＜Use＞ The layered product of the present invention can be used for various applications by utilizing the properties of silicone, for example, silicone elastomer resin, by utilizing its properties such as moderate adhesion to various parts and followability. The laminated body of the present invention is preferably used, for example, in the production steps of various molded bodies, especially in the processes of press forming, vacuum forming, air pressure forming, etc. In this case, it can be used as a mold release material, a buffer material, and a non-slip material. (sealing material) etc. Moreover, the laminated body can also be used as a carrier film for conveying a workpiece, a protective film for protecting a workpiece, and the like.

Among the above, the layered body is preferably used as a mold release material and a buffer material in various molding steps such as press molding, vacuum molding, and air pressure molding. Specifically, in the forming step, the layered body can be arranged between a forming die (mold) and the formed body, and can be used as a buffer for uniformly dispersing the pressure acting on the formed body, or to secure the formed body from the forming die. The purpose of mold release. In addition, among the above, the layered body is more preferably used as a buffer material or a mold release material for press molding. At the time of press forming, the laminated body can be arranged between the work and the press plate when the molded body (work) is pressurized by the press plate. At this time, for example, when the polyimide layer is provided only on one side of the silicone layer, the polyimide layer side may be arranged on the pressure plate side, and the silicone layer side may be arranged on the workpiece side. The temperature at the time of press molding is not particularly limited, but is, for example, 50 to 350°C, preferably 100 to 350°C, more preferably 200 to 350°C, and still more preferably 250 to 320°C. Moreover, as press forming, hydraulic/hydraulic press forming, roll forming, belt press forming, etc. are mentioned.

Furthermore, the laminate of the present invention is preferably used when a circuit board, a semiconductor, other electronic parts, and the like, which are incorporated in an electrical or electronic product, are formed into a formed body. In addition, the press forming is not particularly limited, for example, it is preferably a step performed in the process of manufacturing FPC and components constituting an all-solid-state battery, etc., and also preferably ACF (Anisotropic Conductive Film, anisotropic film) The steps performed when the conductive film) is crimped on the circuit substrate.

Since the laminate of the present invention has a polyimide layer, it is difficult to generate wrinkles or bends, and has high heat resistance, so that the productivity of the formed body can be improved by using it in various molding steps. In addition, the silicone layer has high heat resistance, is not prone to embrittlement, etc., can maintain good cushioning properties for a long time under high temperature heating, and can also suppress dimensional changes. Therefore, the laminate of the present invention can be repeatedly used as a mold release material, a buffer material, and the like for a long period of time.

The laminate of the present invention is also preferably used as a carrier film. When the laminated body is used as a carrier film, it is preferable to have a laminated structure of a silicone layer/polyimide layer, and a conveyed object can be placed on the silicone layer constituting the outermost surface to convey the conveyed object. In particular, if the silicone is a silicone elastomer resin, the silicone layer is slightly adhesive, so it can be used as a non-slip material by being used as the outermost surface of the carrier film. Although the laminated body (carrier film) is conveyed by, for example, a belt conveyor, it is not particularly limited.

In the carrier film, the polyimide layer can be used as a support for the silicone layer. Generally speaking, the carrier film with the silicone layer as the outermost surface usually uses the metal plate as the support. By using the polyimide layer instead of the metal plate, the weight of the carrier can be reduced. Moreover, since the rigidity of a polyimide layer is high, it can be used suitably as a support instead of a metal plate. Furthermore, as the polyimide layer of the present invention, as long as the above-mentioned polyimide layer has high heat resistance, is not easily deformed by heating, and can also reduce the coefficient of linear expansion, even in a high temperature environment (for example, 200 to 350 ℃, preferably about 250 to 320 ℃), it is not easy to thermally deteriorate, and it is not easy to cause abnormalities such as peeling of the silicone layer from the polyimide layer, and it can be used repeatedly for a longer period of time.

The conveyed object may, for example, be a circuit board, a semiconductor, or other electronic parts incorporated in an electrical or electronic product, but is not particularly limited. Moreover, it is preferable that a carrier film is a reflow carrier (reflow carrier) which performs a reflow process in the state which mounted the conveyance (workpiece). In the reflow step, for example, it may be heated to 200° C. or higher, but as described above, the laminated body of the present invention can be used repeatedly even in a high temperature environment, so it can be particularly suitably used as a furnace tray.

[Release material, buffer material, anti-slip material] As another aspect of this invention, the laminated body (X1) used as any one of a mold release material, a buffer material, and an anti-slip material is provided. The laminate (X1) includes a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (B) having a tensile storage modulus at 23°C of 1 GPa or more and the weight reduction rate at 380° C. of the resin layer (A) by thermogravimetric measurement is 9 mass % or less.

Regarding the present layered product (X1), by setting the tensile storage modulus of the resin layer (A) at 23° C. to 100 MPa or less, the following properties, adhesion, The surface tack becomes good. Moreover, by making the tensile storage modulus at 23 degreeC of a resin layer (B) 1 GPa or more, workability|operativity becomes favorable. Therefore, this laminated body (X1) can be used suitably as a mold release material, a buffer material, and an anti-slip material. In addition, the details of the mold release material, the buffer material, and the anti-slip material are as described above, and the resin layer (A) may be used instead of the silicone layer, and the resin layer (B) may be used instead of the polyimide layer. In addition, with regard to this laminate (X1), the resin layer (A) is prevented from embrittlement and the like by making the weight reduction rate of the resin layer (A) at 380° C. 9 mass % or less, and in each of the above-mentioned applications , the laminate (X1) can be used repeatedly for a long time in a high temperature environment. The above-mentioned weight reduction rate of the resin layer (A) at 380° C. is preferably 7 mass % or less, more preferably 6 mass % or less, and further preferably 5 mass % or less, and the weight reduction rate at 380° C. is higher. As low as possible, it should just be 0 mass % or more, for example, 1 mass % or more.

The tensile storage modulus of the resin layer (A) at 23°C is preferable from the viewpoint of the followability to the molded body during press molding, the adhesiveness, or the surface contact adhesion of the resin layer (A). It is 70 MPa or less, more preferably 50 MPa or less, still more preferably 30 MPa or less, and particularly preferably 10 MPa or less. Moreover, 0.1 MPa or more is preferable, 0.5 MPa or more is more preferable, and 1 MPa or more is still more preferable.

The resin constituting the resin layer (A) is not particularly limited, and for example, silicone, olefin-based elastomer, styrene-based elastomer, polyester-based elastomer, urethane-based resin, epoxy-based resin, The resin layer (A) preferably uses silicone as a main component from the viewpoint of being excellent in electrical properties such as heat resistance and insulating properties, and mold releasability, for example, as a fluorine-based elastomer. In the case of using silicone, the silicone described above can be used as the silicone, and the resin layer (A) is the same as the above-mentioned silicone layer.

The tensile storage modulus of the resin layer (B) at 23° C. is preferably 3 from the viewpoint of improving workability or dimensional accuracy, such as suppressing deformation of the laminate when used as a mold release material or the like in a press molding process. GPa or more, more preferably 3.7 GPa or more, still more preferably 4.5 GPa or more, particularly preferably 5 GPa or more, particularly preferably 6 GPa or more, and most preferably 7 GPa or more. Moreover, 15 GPa or less is preferable, 13 GPa or less is more preferable, and 11 GPa or less is still more preferable.

The resin constituting the resin layer (B) is not particularly limited, and examples thereof include curable resins such as polyimide, bismaleimide, and benzodiazepine, thermoplastic polyimide, and polyimide Amines, olefin resins, styrene resins, polyester resins, polycarbonate resins, polyamide resins, polyetherimide resins, polyphenylene sulfide resins, polyphenylene ether resins, polyether ether ketones, etc. Thermoplastic resins such as polyetherketone-based resins, polytetrafluoroethylene resins (PTFE), tetrafluoroethylene-perfluoroalkoxyethylene copolymer resins (PFA), and liquid crystal polymers. Among them, from the viewpoint of heat resistance or mechanical strength, curable resins such as polyimide, bismaleimide, and benzodiazepine, thermoplastic polyimide, polyimide, and the like are preferred. Amorphous thermoplastic resins with a glass transition temperature (Tg) of 300°C or higher, polyetherketone resins such as polyetheretherketone, polytetrafluoroethylene resins (PTFE), and tetrafluoroethylene-perfluoroalkoxyethylene copolymer resins Crystalline thermoplastic resins having a crystal melting temperature (Tm) of 300°C or higher, such as (PFA) and liquid crystal polymers, among them, it is more preferable to use polyimide as the main component resin from the viewpoint of being excellent in heat resistance and rigidity. . In addition, Tg and Tm refer to the DSC (Differential Scanning Calorimetry, differential scanning calorimetry) curve measured by the differential scanning calorimeter at the time of reheating according to JIS K7121:2012, and the value obtained from the DSC curve. In the case of using polyimide, the polyimide described above can be used as the polyimide, and the resin layer (B) is the same as the above-mentioned polyimide layer.

Furthermore, the temperature at which the weight of the resin layer (B) was reduced by 2% by thermogravimetry, the tensile storage modulus at 23° C. and 300° C., the coefficient of linear expansion, and the value of the laminate containing the resin layer (B) were measured. Various characteristics such as the arithmetic mean roughness (Ra) of the outermost surface and the thickness are the same as those of the polyimide layer described above, and therefore the description thereof is omitted. In addition, the tensile failure stress retention rate of the resin layer (A) after heat treatment at 300°C for 3 hours, the tensile failure strain retention rate after heat treatment at 300°C for 3 hours, initial failure stress, initial failure strain, A Various characteristics such as hardness and thickness of the type durometer are the same as those of the silicone layer described above. The thickness ratio of resin layer (A): resin layer (B) is the same as the thickness ratio of silicone layer: polyimide layer. Therefore, their descriptions are also omitted.

In addition, the resin layer (B) may be directly laminated on the resin layer (A), or may be laminated via other layers such as a primer layer. Furthermore, with regard to the primer layer, when the resin layer (A) is a silicone layer, from the viewpoint of securing the adhesion to the primer layer (A), the primer layer preferably contains a silicone resin, More preferably, it contains a silicone resin as a main component. Furthermore, the details of the undercoat layer containing the silicone resin are as described above. Moreover, in the laminated body (X1), the resin layer (B) may be provided only on one surface of the resin layer (A), or may be provided on both surfaces. When the resin layer (B) is provided only on one surface of the resin layer (A), the cover film may be provided on the other surface.

[Laminated products for pressure forming, vacuum forming, and pressure forming] As another aspect of this invention, the laminated body (X2) which is used for any one of press molding, vacuum molding, and air pressure molding is provided. The laminate (X2) includes a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (B) having a tensile storage modulus at 23°C of 1 GPa or more and the weight reduction rate at 380° C. of the resin layer (A) by thermogravimetric measurement is 9 mass % or less.

In this laminate (X2), by setting the tensile storage modulus of the resin layer (A) at 23°C to 100 MPa or less, the follow-up of the molded body during press molding, vacuum molding, and air pressure molding is achieved. The properties, adhesion, and surface touch adhesion become good. In addition, by making the tensile storage modulus of the resin layer (B) at 23° C. to be 1 GPa or more, workability is improved, and it can be suitably used as a mold release material or a buffer material in each of these molding processes. . In addition, the details of pressure forming, vacuum forming, or pressure forming, or mold release material or buffer material are as described above, and resin layer (A) can be used instead of silicone layer, and resin layer (B) can be used instead of polyamide Amine layer. In addition, in the present layered product (X2), the resin layer (A) is prevented from becoming brittle by making the weight reduction rate at 380° C. of the resin layer (A) determined by thermogravimetric measurement to be 9 mass % or less. etc., the laminated body can be used repeatedly for a long time in a high temperature environment. The structure of the laminated body (X2) in this form is the same as that demonstrated in the above-mentioned laminated body (X1), and therefore a detailed description is omitted.

[carrier film] As another aspect of this invention, the laminated body (X3) used for a carrier film is provided. The laminate (X3) includes a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (B) having a tensile storage modulus at 23°C of 1 GPa or more Moreover, the weight reduction rate at 380 degreeC of the said resin layer (A) by thermogravimetric measurement is 9 mass % or less.

In the present layered product (X3), the tensile storage modulus of the resin layer (A) at 23° C. is 100 MPa or less, so that the surface touch adhesion of the resin layer (A) becomes good, and by When the tensile storage modulus of the resin layer (B) is 1 GPa or more, a certain strength can be ensured, and it can be suitably used as a carrier film. The details of the carrier film are as described above, and the resin layer (A) may be used instead of the silicone layer, and the resin layer (B) may be used instead of the polyimide layer. In addition, in this layered product (X3), the resin layer (A) is prevented from being brittle by making the weight reduction rate at 380° C. of the resin layer (A) determined by thermogravimetric measurement to be 9 mass % or less. etc., the laminated body (X) can be used repeatedly for a long time in a high temperature environment, and it is also suitable as a furnace tray or the like. The structure of the laminated body (X3) in this embodiment is the same as the structure explained in the above-mentioned laminated body (X1), so the detailed description is abbreviate|omitted. [Example]

Hereinafter, the present invention will be described in further detail by way of examples, but the present invention is not limited by these examples.

In this Example and a comparative example, evaluation was performed as follows.

(1) Weight reduction rate at 380°C The sample collected from the silicone layer was heated under the following conditions using a simultaneous differential thermogravimetric measuring device (TG-DSC), the weight loss at 380°C was measured, and the weight loss at 380°C was calculated Ratio relative to initial weight. Measuring device: "STA200RV", manufactured by Hitachi High-Tech Science Co., Ltd. Measurement conditions: The temperature was raised from 35°C to 800°C at 20°C/min, and the measurement was performed. Implemented in an atmospheric atmosphere.

(2) Tensile failure stress retention rate and tensile failure strain retention rate For the film containing the silicone raw material for forming the silicone layer of the laminate produced by the method described below, referring to JIS K7127:1999, a short strip-shaped test piece with a width of 10 mm was fixed at a distance of 20 mm between the clamps. Under the environment of 23°C and 50 RH%, the tensile tester (manufactured by Shimadzu Corporation, Autograph AGS-X) was used for pulling at a tensile speed of 500 mm/min, and the initial tensile failure stress and tensile force were measured. Destruction strain. In addition, similarly, about the test piece, heat treatment was performed by heating in a thermostatic bath adjusted to 300° C. for 3 hours, and the tensile failure stress and the tensile failure strain were similarly measured for the test piece after the heat treatment. And as the tensile failure stress and tensile failure strain after heat treatment. In addition, the measurement is performed in the MD direction. The ratio of the tensile failure stress after heat treatment to the initial tensile failure stress was taken as the retention rate of tensile failure stress after heat treatment at 300° C. for 3 hours. In addition, the ratio of the tensile failure strain after the heat treatment to the initial tensile failure strain was taken as the retention rate of the tensile failure strain after the heat treatment at 300° C. for 3 hours.

(3) Transfer amount of low molecular weight cyclosiloxane component (Pressure forming) The dust-free paper was superimposed on the obtained laminates of Examples 1 and 4, and the pressure was carried out by a press for 10 minutes under the conditions of a temperature of 100° C. and a pressure of 10 MPa, and the low-molecular-weight cyclosiloxane was pressed without The transfer amount on the dust paper was evaluated. In the case of a laminate of one-sided polyimide layers, press the silicone layer with dust-free paper; in the case of a laminate of two-sided polyimide layers, laminate the dust-free paper on one side of the polyimide layer. amine layer to pressurize.

(Quantitative determination of low molecular weight cyclosiloxane) As an internal standard solution, 5 mg of decamethylcyclopentasiloxane (cyclosiloxane pentamer (D5 siloxane)) was accurately weighed and put into After putting it in a 100 mL volumetric flask, it is obtained by diluting to volume with acetone. Cut out 25 cm ² of the pressurized lint-free paper, weigh the sample accurately, and put it into the sample bottle. Weigh 10 mL of the above internal standard solution and put it into the above sample bottle. After capping the sample vial, wrap the parafilm around the sample vial, and immerse the sample bottle for 16 hours at room temperature to perform extraction treatment. Then, with respect to the acetone solution in the sample vial, the content of the low molecular weight cyclosiloxane was measured by gas chromatography (GC) under the following measurement conditions. In addition, after maintaining the column temperature at 70°C for 1 minute, the temperature was increased at a rate of 25°C/min, and the temperature was raised to 320°C and held for 5 minutes before measurement.

(measurement conditions) ・Measuring device: GC-2010 Plus (manufactured by Shimadzu Corporation) ・Column: Ultra ALLOY Capillary Column-UA1(MS/HT) (100% dimethylpolysiloxane, length 30 m, inner diameter 0.25 mm, film thickness 0.1 μm) ・Carrier gas: Helium ・Flow rate: 1 mL/min ・Detector: FID (Flame Ionization Detector, flame ionization detector)

(Calculation method of cyclosiloxane content) Based on the internal standard D5 siloxane amount and GC peak area, according to the Dn (Dn is D4-D20 siloxane, which is a cyclosiloxane with dimethylsiloxane units derived from each cyclosiloxane) oxane), the respective cyclosiloxanes D4 to D20 were quantified, and their total content was evaluated. Furthermore, for D5 siloxane, the amount of D5 siloxane in the internal standard is subtracted and then quantified. In addition, the content of less than 30 mass ppm was set as the detection limit value "ND".

(4) Thickness change after pressurization A high-temperature vacuum press (manufactured by Kitagawa Seiki Co., Ltd.) was used for a test piece having a size of 10 cm×10 cm cut out from the obtained laminates of Example 1 and Comparative Example 1. Under the conditions of vacuum, temperature 300°C, pressing pressure 100 kg/cm ² , and holding time 10 minutes, press molding was performed, and the thickness before pressing and the thickness after pressing were measured at any 5 locations, and 5 locations were used. The average value of the thickness variation was calculated.

(5) Tensile storage modulus For a polyimide film forming a polyimide layer, or a film containing a silicone resin material (thickness 100 μm) forming a silicone layer produced by the method described below, according to JIS K7244-4:1999 , and the tensile storage modulus at 23°C and 300°C was measured under the following conditions using a viscoelasticity spectrometer. Measuring device name: "DVA-200", manufactured by IT Measurement & Control Co., Ltd. Distance between chucks: 25 mm Strain: 0.07% Width: about 4 mm Temperature: -50～350℃ Frequency: 1 Hz Measurement method: stretching Heating rate: 3℃/min Measurement direction: MD

(6) Thermogravimetric measurement (temperature at which weight is reduced by 2%) Thermogravimetric measurement is performed under the following conditions using a differential thermo-thermogravimetric simultaneous measurement device (TG-DSC) to heat the sample collected from the polyimide layer, and read the value when the weight is reduced by 2% relative to the initial weight. temperature. Measuring device: "STA200RV", manufactured by Hitachi High-Tech Science Co., Ltd. Measurement conditions: The temperature was raised from 35°C to 800°C at 20°C/min, and the measurement was performed. Implemented in an atmospheric atmosphere.

(7) Linear expansion coefficient The polyimide film forming the polyimide layer was measured under the following measurement conditions using a thermomechanical analyzer. Measuring device: "TMA/SS7100", manufactured by Hitachi High-Tech Science Co., Ltd. Specimen width: 3 mm Distance between chucks: 10 mm Mode: Tensile Measurement direction: MD Temperature conditions: heating to 15-330°C at a rate of 5°C/min, and then cooling down to 15°C at a rate of 5°C/min, measure the length of the sample at 300°C and 30°C during the cooling process, and calculate the coefficient of linear expansion (1 /°C). In addition, the measurement direction is made into MD.

(8) Arithmetic mean roughness (Ra) of polyimide layer The arithmetic mean roughness (Ra) of the outermost polyimide layer constituting the laminate was measured using a three-dimensional non-contact surface profile measuring instrument (trade name "VertScan2.0 R5200G" manufactured by Ryoka Systems) at a 5x objective lens, The measurement was performed under the conditions of a measurement range of 948.76 μm×711.61 μm.

(Manufacturing method of silicone film for tensile failure stress retention, tensile failure strain and tensile storage modulus evaluation) Two cover films (biaxially stretched PETT (Polyethylene Terephthalate, polyethylene terephthalate) film, "DIAFOIL T-100" manufactured by Mitsubishi Chemical Co., Ltd., Thickness: 100 μm), each raw material of the silicone resin layer described in Table 1 was supplied, and a resin accumulation portion was formed on the roller under the condition of a roller temperature of 80°C, thereby producing a cover film/silicone layer/ A laminate of cover films. The obtained laminate with the cover film was irradiated with γ-rays at an absorbed dose of 50 kGy to crosslink the silicone elastomer resin of the silicone layer, the cover film was peeled off from the cross-linked laminate, and used as a Silicone film for evaluation.

Example 1 The primer containing the addition type silicone resin, the adhesion improver, and the hardening catalyst diluted with a toluene solvent was applied to the polyamide by roll coating so that the thickness after drying was 0.3 μm. After the amine film (“Upilex-S” manufactured by Ube Industries, Ltd., thickness: 25 μm) was applied, it was dried at 120° C. for 30 seconds and heat-treated to obtain a polyimide film with a primer layer on one side. .

Using a kneadable silicone elastomer resin ("TSE2323-5U" manufactured by Momentive High-tech Materials Co., Ltd., containing 1.1% by mass of titanium oxide as metal oxide, tensile storage modulus of 2.6 MPa (23°C), A type The durometer hardness is 50 (manufacturer's nominal value)) as the raw material of the silicone resin layer, on the undercoat layer of the polyimide film supplied along two calenders with a diameter of 100 mm, and as the cover film. The above-mentioned silicone elastomer resin was supplied between biaxially stretched PET films (“DIAFOIL T-100” manufactured by Mitsubishi Chemical Co., Ltd., thickness: 100 μm), and a resin accumulation portion was formed on the roll at a roll temperature of 80°C. Thus, a laminate comprising a polyimide layer/silicone layer was obtained. Furthermore, a cover film is attached on the silicone layer.

The obtained laminate with the cover film was irradiated with γ-rays at an absorbed dose of 50 kGy to crosslink the silicone elastomer resin to obtain a laminate in which the polyimide layer and the silicone layer were integrated body. The thickness of the silicone layer is 100 μm. The cover film was peeled off from the obtained laminated body, and it was set as the laminated body for evaluation. For the laminate, the weight loss rate at 380°C, the tensile stress retention rate at failure and the tensile failure strain retention rate after heat treatment at 300°C for 3 hours were evaluated. The results are shown in Table 1. In addition, when the polyimide layer was evaluated, the tensile storage modulus at 300°C was 4.0 GPa, the tensile storage modulus at 23°C was 9.7 GPa, and the temperature at which the weight decreased by 2% was 588°C , the coefficient of linear expansion is 11×10 ^-6 /℃. Moreover, the arithmetic mean roughness (Ra) of the outermost surface containing the polyimide layer of the laminated body was 2.6 nm.

Example 2 Except for the use of a kneadable silicone elastomer resin (“TSE2323-7U” manufactured by Momentive High-tech Materials Co., Ltd., containing 0.8% by mass of titanium oxide as a metal oxide, the tensile storage modulus is 5.7 MPa (23°C), A A laminated body was produced in the same manner as in Example 1, except that the hardness of the type durometer was 70 (manufacturer's nominal value)) as a raw material for the silicone resin layer.

Example 3 In addition to using a kneadable silicone elastomer resin ("X-30-3888-U" manufactured by Shin-Etsu Chemical Co., Ltd. (containing 2.4% by mass of iron oxide as a metal oxide and 0.3-1% by mass of carbon black), A laminate was produced in the same manner as in Example 1 except that the tensile storage modulus was 5.2 MPa (23° C.), and the A-type durometer hardness was 60 (manufacturer’s nominal value) as the raw material of the silicone resin layer.

Example 4 A silicone layer was formed between the undercoat layers of the two polyimide films except that a polyimide film with an undercoat layer on one side formed in the same manner as in Example 1 was used instead of the cover film to obtain a polyimide film containing a polyimide film. Except for the laminate of the amine layer/silicone layer/polyimide layer, it was carried out in the same manner as in Example 1.

Example 5 A laminate was produced in the same manner as in Example 4, except that a kneadable silicone elastomer resin (“TSE2323-7U” manufactured by Momentive High-Tech Materials Co., Ltd., containing 0.8% by mass of titanium oxide) was used as a raw material for the silicone resin layer .

Example 6 Except for using a kneadable silicone elastomer resin (“X-30-3888-U” manufactured by Shin-Etsu Chemical Co., Ltd., containing 2.4% by mass of iron oxide and 0.3-1% by mass of carbon black) as the raw material of the silicone resin layer Other than that, it carried out similarly to Example 4, and produced the laminated body.

Comparative Example 1 A laminate was produced in the same manner as in Example 1, except that a kneadable silicone elastomer resin (“TSE2571-5U” manufactured by Momentive High-tech Materials Co., Ltd., without metal oxide) was used as a raw material for the silicone resin layer.

[Table 1] unit Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 silicone layer 2323-5U 100 μm 100 μm 2323-7U 100 μm 100 μm X-30-3888-U 100 μm 100 μm 2571-5U 100 μm Polyimide layer one-sided one-sided one-sided both sides both sides both sides one-sided TGA (Thermogravimetry Analysis, Thermogravimetric Analysis) (weight loss rate at 380°C) % 4.1 4.0 4.3 4.1 4.0 4.3 9.6 Tensile failure stress (initial) MPa 10.9 11.9 10.2 10.9 11.9 10.2 10.0 Tensile failure stress (300℃, after 3 hr) MPa 4.9 6.0 5.7 4.9 6.0 5.7 - Tensile failure stress retention (after heat treatment at 300℃, 3 hr) % 45 50 56 45 50 56 - Tensile failure strain (initial) % 800 574 364 800 574 364 545 Tensile failure strain (300℃, after 3 hr) % 372 273 317 372 273 317 - Tensile failure strain retention (after heat treatment at 300℃, 3 hr) % 47 48 87 47 48 87 - Cyclosiloxane transfer volume mass ppm 10484 ND Thickness change after press forming μm 2.6 5.2 *"-" in Comparative Example 1 means that the measurement could not be performed.

As shown in Table 1, in Examples 1 to 6, since the weight loss rate of the silicone layer at 380°C is low and the heat resistance is high, the failure stress retention ratio and failure strain retention ratio after heat treatment are higher, even if Long-term repeated use in high temperature environment also maintains high performance. Therefore, even if the laminated body is used repeatedly in a high temperature environment as a release material, a buffer material, a carrier film, etc., the cushioning properties of the silicone layer are not lost, and embrittlement is prevented. In addition, as shown in Examples 4 to 6, when the polyimide layers are provided on both sides, the adhesion amount of the low molecular weight siloxane to the press in the press test is reduced, which can be understood as being difficult to adhere to the molded body or the press. Forming dies cause contamination. Furthermore, thickness variation (dimension variation) caused by press molding is suppressed, and even if it is repeatedly used under press molding, the thickness is not easily changed, sufficient cushioning properties are maintained, and it can be understood that it is excellent in durability. On the other hand, in Comparative Example 1, since the weight loss rate of the silicone layer at 380° C. was high and the heat resistance was low, embrittlement occurred after the heat treatment, and the failure stress and failure strain could not be measured. In addition, the thickness (dimension change) due to press forming was larger than that in the examples. Therefore, it is difficult to repeatedly use it for a long time in a high temperature environment as a mold release material, a buffer material or a carrier film.

Claims (16)

A laminate comprising a silicone layer and a polyimide layer, and The weight reduction rate in 380 degreeC of the said silicone layer by thermogravimetry is 9 mass % or less. The laminate according to claim 1, wherein a polyimide layer is provided on both surfaces of the silicone layer. The laminate according to claim 1, wherein the polyimide layer is provided only on one side of the silicone layer, and a cover film is provided on the other side of the silicone layer. The laminate according to any one of claims 1 to 3, wherein the silicone layer contains 0.1 to 10 mass % of titanium oxide. The laminate according to any one of claims 1 to 4, wherein the tensile storage modulus of the polyimide layer at 23°C is greater than the tensile storage modulus of the silicone layer at 23°C. The laminate according to any one of claims 1 to 5, wherein the tensile failure stress retention rate of the silicone layer after heat treatment at 300° C. for 3 hours is 10% or more. The laminate according to any one of claims 1 to 6, wherein the tensile failure strain retention rate of the silicone layer after heat treatment at 300° C. for 3 hours is 10% or more. The laminate according to any one of claims 1 to 7, wherein the thickness ratio of the silicone layer: the polyimide layer is 99:1 to 20:80. The laminate according to any one of claims 1 to 8, which is used as any one of a mold release material, a buffer material, and a non-slip material. The laminate according to any one of claims 1 to 8, which is used for any one of press forming, vacuum forming, and air pressure forming. The laminate according to any one of claims 1 to 8, which is used as a carrier film. A laminate comprising a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (B) having a tensile storage modulus at 23°C of 1 GPa or more ,and The resin layer (A) has a weight reduction rate of 9 mass % or less at 380° C. obtained by thermogravimetric measurement, And the said laminated body is used as any one of a mold release material, a buffer material, and an anti-skid material. A laminate comprising a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (B) having a tensile storage modulus at 23°C of 1 GPa or more ,and The resin layer (A) has a weight reduction rate of 9 mass % or less at 380° C. obtained by thermogravimetric measurement, In addition, the above-mentioned laminated body is used for any one of press molding, vacuum molding, and air pressure molding. A laminate comprising a resin layer (A) having a tensile storage modulus at 23°C of 100 MPa or less, and a resin layer (B) having a tensile storage modulus at 23°C of 1 GPa or more ,and The resin layer (A) has a weight reduction rate of 9 mass % or less at 380° C. obtained by thermogravimetric measurement, And the said laminated body is used as a carrier film. A method of using the layered product according to any one of claims 1 to 8, wherein the layered product is used as a mold release material or a buffer material during molding. A method of using the layered product according to any one of claims 3 to 8, wherein when the layered product is used as a mold release material or a buffer material during molding, the cover film is peeled off, and the polyimide layer side is disposed on the molding On the mold side, the silicone layer side is arranged on the molded body side.