JP2014091782A - Prepreg preservation method, laminate, and laminate packaging material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a prepreg preservation method, a laminate, and a laminate packaging material, capable of holding desmear resistance.SOLUTION: This invention provides [1] a prepreg preservation method for preserving a laminate of at least one sheet-like drying agent and at least one prepreg made by impregnating glass cloth with a resin composition, [2] the laminate, and [3] a laminate packaging material containing the laminate.

Description

  The present invention relates to a prepreg storage method, a laminate, and a laminate package, and more particularly to a prepreg storage method using a sheet-like desiccant, a laminate, and a laminate package.

  As electronic devices become smaller and more sophisticated, high-frequency signals are being processed at computers and information equipment terminals to process large amounts of data at high speed. However, the transmission loss of electrical signals increases as the frequency increases. Development of a printed wiring board corresponding to high frequency is strongly demanded. Transmission loss in high-frequency circuits is greatly affected by the dielectric loss determined by the dielectric characteristics of the insulating layer (dielectric) around the wiring, and printed circuit board substrates (especially insulating resin) require low dielectric constant and low dielectric loss tangent. It is done.

  Conventionally, heat-resistant thermoplastic resin (engineering plastics) polyphenylene ether (PPO or PPE) resin has been known as a material with good dielectric properties, but for application to insulating materials for printed wiring boards. However, it was necessary to improve the heat resistance that can withstand the solder connection process during mounting and the solvent resistance and chemical resistance in other processes during the production of printed wiring boards. As a method for improving the heat resistance and solvent resistance, a method of modifying a polyphenylene ether resin with a thermosetting resin has been proposed. For example, as shown in Patent Document 1, a curable resin in which a cyanate ester resin is blended with a polyphenylene ether resin, which is used as a resin film using a cyanate ester resin having the lowest dielectric constant among thermosetting resins. A composition. Similarly, as a resin composition using a cyanate ester-based modified resin, a mixture (or pre-reaction product) of a polyfunctional maleimide and a polyfunctional cyanate ester disclosed in Patent Document 2, and a polyphenylene ether are used. Examples thereof include a resin composition with a resin, and a resin composition of a modified cyanate resin and a polyphenylene ether resin obtained by reacting a modified phenol resin and a cyanate ester resin shown in Patent Document 3. In addition, Patent Document 4 reports a prepreg using a resin composition having a modified phenol product derived from a polyphenylene ether resin, an epoxy resin, an epoxy curing agent, and silica powder.

Japanese Patent Publication No. 1-53700 Japanese Examined Patent Publication No. 63-33506 Japanese Patent Laid-Open No. 5-311071 JP-A-10-212336

When using a prepreg impregnated with the above resin in a glass cloth, if the multilayer wiring board is manufactured using a product that has been allowed to stand for a certain period of time after the prepreg is manufactured and desmear treatment is performed, the resin itself in the prepreg is often eluted. Thus, it was found that the desmear resistance is lowered.
In order to improve the water resistance of the prepreg, a method of packing with silica gel or the like can be considered, but the effect of moisture in the air is received from the end rather than on the prepreg, so the improvement effect is limited .
The present invention relates to a prepreg storage method, a laminate, and a laminate package that can retain desmear resistance.

The inventor of the present invention pays attention to the fact that the resin used in the prepreg is easily affected by water, and the laminate is stored by stacking the sheet-like desiccant and the prepreg, thereby suppressing the water absorption amount of the prepreg. It has been found that desmearability can be improved.
The present invention has been completed based on such findings.

That is, the present invention relates to the following [1] to [20].
[1] A method for preserving a prepreg, characterized by storing a laminate in which at least one sheet-like drying material and at least one prepreg obtained by impregnating a glass cloth with a resin composition are stored.
[2] The method for storing a prepreg according to [1], wherein the sheet-like desiccant is disposed on at least both outermost surfaces of the laminate.
[3] The method for storing a prepreg according to [1] or [2], wherein the maximum moisture absorption amount of the sheet-like desiccant is 0.5 g / m ² or more.
[4] The storage of the prepreg according to any one of [1] to [3], wherein a ratio of the area of one side of the sheet-like desiccant to the area of one side of the prepreg is 0.8 or more. Method.
[5] The method for storing a prepreg according to any one of [1] to [4], wherein the thickness of the sheet-like desiccant is 10 to 500 μm.
[6] The method for storing a prepreg according to any one of [1] to [5], wherein the sheet-like desiccant is made of a desiccant resin composition in which a desiccant is kneaded with a thermoplastic resin.
[7] The method for preserving a prepreg according to any one of [1] to [6], wherein the resin composition of the prepreg contains a resin having a cyanate group.
[8] The method for preserving a prepreg according to any one of [1] to [7], wherein the resin composition of the prepreg further contains an inorganic filler.
[9] The method for storing a prepreg according to any one of [1] to [8], wherein the laminate is stored in a package and stored.
[10] A laminate in which at least one sheet-like drying material and at least one prepreg obtained by impregnating a glass cloth with a resin composition are stacked.
[11] The laminate according to [10], wherein the sheet-like desiccant is disposed on both outermost surfaces of the laminate.
[12] The laminate according to [10] or [11], wherein a maximum moisture absorption amount of the sheet-like desiccant is 0.5 g / m ² or more.
[13] The laminate according to any one of [10] to [12], wherein the ratio of the area of one side of the sheet-like desiccant to the area of one side of the prepreg is 0.8 or more.
[14] The laminate according to any one of [10] to [13], wherein the thickness of the sheet-like desiccant is 10 to 500 μm.
[15] The laminate according to any one of [10] to [14], wherein the resin composition of the prepreg contains a resin having a cyanato group.
[16] The laminate according to any one of [10] to [15], wherein the resin composition of the prepreg further contains an inorganic filler.
[17] A laminate package comprising the laminate according to any one of [10] to [16] and a package containing the laminate.
[18] The laminate package according to [17], wherein the package has a sealing function.
[19] The laminate package according to [17] or [18], wherein the package has a moisture absorption function.
[20] The laminate package according to any one of [17] to [19], wherein the package is subjected to an aluminum vapor deposition process.

  INDUSTRIAL APPLICABILITY The present invention can provide a prepreg storage method, a laminate, and a laminate package that can maintain desmear resistance.

Hereinafter, embodiments of the present invention will be described in detail.
The prepreg storage method of the present invention is characterized by storing a laminate in which at least one sheet-like drying material and at least one prepreg formed by impregnating a glass cloth with a resin composition are stacked. . By storing the prepreg and the sheet-like desiccant in a laminated state in this way, the area where the prepreg is exposed to air is reduced, and the moisture content in the air that the sheet-like desiccant contacts is reduced. Therefore, the influence of water in the air of the resin composition impregnated in the prepreg can be minimized. For this reason, it is thought that the desmear resistance in a desmear process can be hold | maintained.

[Sheet desiccant]
Although the sheet-like desiccant used in the present invention is not particularly limited, for example, a desiccant resin composition obtained by kneading a desiccant in a thermoplastic resin into a sheet can be used. By using a desiccant resin composition, the sheet-like desiccant has a suitable flexibility and can simultaneously protect the surface of the prepreg. By using a flexible sheet-shaped desiccant, not only drying of the prepreg but also surface protection of the prepreg can be performed simultaneously.
Further, by using the desiccant resin composition, it is possible to prevent contamination of the prepreg because foreign substances are less likely to fall compared to a sheet-like desiccant made of paper or the like.

  The thermoplastic resin used in the desiccant resin composition is not particularly limited. For example, polyethylene, polypropylene, polycarbonate, polyamide, ethylene-vinyl acetate copolymer, ethylene-methacrylate copolymer, polyvinyl chloride, polystyrene , Polyester, polyacrylic acid ester, polyvinylidene chloride, acrylonitrile butadiene styrene copolymer (ABS), polylactic acid, polyacetal, polyacrylonitrile, polyimide, polybutylene terephthalate (PBT), etc., one or two of these The above can be used.

Although it does not specifically limit as a desiccant used for a desiccant resin composition, For example, magnesium sulfate, copper sulfate, cobalt chloride, calcium chloride, magnesium chloride etc. are mentioned. Among these, magnesium sulfate is preferable, more preferably magnesium sulfate represented by the formula MgSO ₄ · nH ₂ O (where 0 ≦ n ≦ 3), and more preferably anhydrous magnesium sulfate.
Although it does not specifically limit as a desiccant resin composition, For example, resin described in Unexamined-Japanese-Patent No. 2008-056784 can be used.

Maximum moisture content of the sheet-like drying material is preferable to be 0.5 g / m ² or more, further preferable to be 1.0 g / m ² or more, and particularly preferably 1.3 g / m ² or more. Although an upper limit is not specifically limited, For example, it is 5.0 g / m < ² >. When the maximum moisture absorption amount is 0.5 g / m ² or more, the time during which the prepreg can be protected from moisture in the air can be kept longer. The maximum amount of moisture absorption means the amount of moisture absorption with respect to the surface area of the sheet-like desiccant. The maximum amount of moisture absorption is calculated from the weight change before and after being left in a constant temperature and humidity chamber at a temperature of 85 ° C./85% relative humidity for 24 hours.

  The sheet-like desiccant preferably has a hygroscopic property capable of holding a relative humidity of 50% or less, more preferably has a hygroscopic property capable of maintaining a relative humidity of 40% or less, and a relative humidity of 35% or less. It is particularly preferable to have a hygroscopic property that can be retained. Although a minimum is not specifically limited, For example, it is hygroscopic which can hold | maintain a relative humidity 0%. When the relative humidity is 50% or less, it is possible to further improve the desmear resistance maintenance performance of the prepreg. Hygroscopicity can be measured by placing a sheet-like desiccant in a sealable container having a relative humidity of 90% or higher and confirming the relative humidity in the container after 24 hours.

  In addition, it is preferable to use a sheet-like desiccant having a moisture absorbing layer composed of the desiccant resin composition and a moisture permeable protective layer on one side or both sides of the moisture absorbing layer because the amount of dust generation can be suppressed. . At this time, a protective layer having no moisture permeability may be provided on one side of the protective layer having moisture permeability on one side, but a protective layer having moisture permeability is provided on both sides from the point of protecting the prepreg from moisture in the air. Some are preferred.

The shape of the sheet-like desiccant is preferably substantially the same as the shape of the prepreg.
Further, the ratio [(sheet-like desiccant area) / (prepreg area)] of the area of one side of the sheet-like desiccant to the area of one side of the prepreg is preferably 0.8 or more, and 0.9 or more More preferably, it is more preferably 1.0 or more. The upper limit is not particularly limited, but is preferably 1.8 or less for economy. By setting it as such an area ratio, the surface of a prepreg can be covered and the influence of the water | moisture content contained in the air can be minimized.

  10-500 micrometers is preferable, as for the thickness of a sheet-like desiccant, 20-300 micrometers is more preferable, and 25-200 micrometers is still more preferable.

[Prepreg]
The prepreg used in the present invention is formed by impregnating a glass cloth with a resin composition.

The resin composition used for the prepreg preferably contains a thermosetting resin, and more preferably contains a thermosetting resin and an inorganic filler.
The thermosetting resin may be anything as long as it has thermosetting properties, but it preferably contains a resin having a cyanato group or a resin having an epoxy group, and is notable for a resin having a cyanato group. The effect is expressed.

Examples of the resin having a cyanato group include a resin having at least two cyanate groups in one molecule. More specifically, for example, novolak-type cyanate resin, bisphenol A-type cyanate resin, bisphenol E-type cyanate resin, bisphenol F-type cyanate resin, tetramethylbisphenol F-type cyanate resin, and the like, one or two of these A mixture of seeds or more can be used. Among these, bisphenol A type cyanate resin or novolac type cyanate resin is preferable from the viewpoints of dielectric properties, heat resistance, flame retardancy, low thermal expansion, and low cost. The average number of repetitions of the novolak-type cyanate resin is not particularly limited, but is preferably 1 to 30 from the viewpoint of having appropriate crystallinity and obtaining the strength of the cured product.
As a commercial product of bisphenol A type cyanate resin that can be used as a resin having at least two cyanate groups in one molecule, Lonza Japan Co., Ltd., trade name Arocy B-10 can be mentioned. Moreover, as a commercial item of a novolak-type cyanate resin, Lonza Japan Co., Ltd. make, brand name Primaset PT-30 (weight average molecular weight 500-1,000), brand name Primaset PT-60 (weight average molecular weight 2,000) ~ 3,000).

The resin having a cyanato group is preferably used after partially reacting.
The organic solvent used for the reaction of the resin having a cyanato group is not particularly limited, and examples thereof include toluene, mesitylene, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and the like. In particular, the resin in which toluene and mesitylene have a cyanate group (particularly in one molecule). And a resin having at least two cyanato groups) is preferable because of high solubility.

In the present invention, it is preferable to pre-react in an organic solvent in advance so that the reaction rate (disappearance rate) of the resin having a cyanate group is 40 to 70 mol%. When the reaction rate of the resin having a cyanato group is 40 mol% or more, the compatibility between the obtained thermosetting resin and a general-purpose organic solvent is increased, and the heat resistance and the copper foil adhesiveness are improved. Further, when the reaction rate of the resin having a cyanate group is 40 mol% or more, it becomes easy to produce an A-stage varnish (thermosetting resin composition) by the obtained thermosetting resin composition, and the B-stage coating is performed. Tack is less likely to occur during construction.
In addition, when the reaction rate of the resin having a cyanate group is 70 mol% or less, the resulting thermosetting resin composition is easily dissolved in a general-purpose organic solvent, the A-stage varnish is easily produced, and the varnish moldability is increased. Will improve.
In addition, the reaction rate of resin which has a cyanato group is calculated | required from the measurement result of GPC measurement. Specifically, the peak area of the cyanate resin appearing in the vicinity of a predetermined holding time is compared between the solution before the reaction containing a resin having a cyanate group and the solution after the reaction of this solution. The disappearance rate of the peak area of the solution after the reaction relative to the peak area of the solution before the reaction corresponds to the reaction rate.

  The resin composition used for the prepreg may contain an inorganic filler, such as crushed silica, fused silica, mica, talc, short glass fiber or fine powder, and hollow glass, calcium carbonate, quartz powder, metallic water. Japanese products are listed. The blending amount is preferably 10 to 300 parts by mass, more preferably 100 to 250 parts by mass, and 150 to 250 parts by mass in terms of solid content with respect to 100 parts by mass of the thermosetting resin composition. It is particularly preferred. If it is 10-300 mass parts, sufficient rigidity of a base material, moisture heat resistance, a flame retardance, the tolerance with respect to the erosion by a plating solution, etc. will be obtained.

  In the present invention, it is desirable to use a curing accelerator in the resin composition used for the prepreg in order to improve heat resistance, flame retardancy, copper foil adhesion, and the like. Examples of curing accelerators include organometallic salts such as zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, imidazoles and their derivatives, tertiary amines and quaternary ammonium salts. . In addition, known thermoplastic resins, elastomers, organic fillers, flame retardants and the like can be used in combination. Examples of thermoplastic resins that can be blended in the resin composition include tetrafluoroethylene, polyethylene, polypropylene, polystyrene, polyphenylene ether resin, phenoxy resin, polycarbonate resin, polyester resin, polyamide resin, polyimide resin, xylene resin, and petroleum resin. And silicone resin. Examples of elastomers that can be blended in the resin composition include polybutadiene, acrylonitrile, epoxy-modified polybutadiene, maleic anhydride-modified polybutadiene, phenol-modified polybutadiene, and carboxy-modified acrylonitrile. Examples of organic fillers that can be blended in the resin composition include organic powders such as silicone powder, tetrafluoroethylene, polyethylene, polypropylene, polystyrene, and polyphenylene ether. Examples of flame retardants that can be blended in the resin composition include triphenyl phosphate, tricresyl phosphate, trisdichloropropyl phosphate, phosphoric ester compounds, phosphazenes, phosphorous flame retardants such as red phosphorus, antimony trioxide, Examples include inorganic flame retardant aids such as zinc molybdate. In addition, the resin composition may appropriately contain compounding agents such as an ultraviolet absorber, an antioxidant, a photopolymerization initiator, a fluorescent brightening agent, and an adhesion improver. Examples of compounding agents that can be incorporated into the resin composition include UV absorbers such as benzotriazoles, antioxidants such as hindered phenols and styrenated phenols, light such as benzophenones, benzyl ketals, and thioxanthones. Examples thereof include polymerization initiators, fluorescent brighteners such as stilbene derivatives, urea compounds such as urea silane, and adhesion improvers such as silane coupling agents.

  As the glass cloth used for the prepreg, those having a thickness of 10 μm or less are preferable. Specific examples of the glass cloth include WEX-1017, WEX-1027, WEX-1037, and WEX-1086 (product name, manufactured by Asahi Kasei E-Materials Co., Ltd.).

[Packaging body]
The package used in the present invention is not particularly limited as long as it can store a laminate of a sheet-like desiccant and a prepreg.
The packing body preferably has a sealing function in order to prevent moisture in the air from entering. An example of a package having a sealing function is a bag with a chuck.
The package preferably has a hygroscopic function, and the interior is more preferably formed of a desiccant resin composition having a hygroscopic function. Here, the same desiccant resin composition as the above desiccant resin composition can be used.
Moreover, in order to obtain moisture-proof resistance notably, it is suitable for the package to have been subjected to an aluminum vapor deposition treatment, and it is more preferred that the exterior is composed of an aluminum vapor deposition film.

[Storage method and laminate]
In the method for storing a prepreg of the present invention, a laminate in which at least one sheet-like drying material and at least one prepreg obtained by impregnating a glass cloth with a resin composition are stored.
Here, it is preferable that the laminated body which laminated | stacked the sheet-like desiccant and the prepreg arrange | positions a sheet-like desiccant on both the outermost surface sides of this laminated body. Thereby, it becomes difficult for moisture in the air to be taken into the laminated body, and a remarkably higher desmear resistance is obtained.
In addition, the configuration of the laminate is not particularly limited. For example, a laminate a in which a plurality of prepregs are stacked and a sheet-shaped drying material is stacked on both outermost surfaces (two surfaces), or a prepreg and a sheet-shaped drying are stacked. The laminated body b which laminated | stacked the material alternately is mentioned. Among these, in this invention, the laminated body a is preferable from a viewpoint of economical efficiency.
In the method for preserving the prepreg of the present invention, it is preferable to store the laminated body in a packaging body in order to prevent absorption of moisture in the air. That is, it is preferable to store the laminate in a state of a laminate package including the laminate and the package that stores the laminate. The above-mentioned thing can be used as a package.
The storage time is appropriately set according to the purpose and is not particularly limited, but is, for example, 3 hours to 1 year.

  Next, the present invention will be described in more detail with reference to the following examples, but these examples do not limit the present invention.

[Evaluation method]
<Desmear resistance>
Multilayer wiring by placing an inner layer board processed circuit prepared by the following method, a prepreg to be evaluated, and an electrolytic copper foil with a thickness of 18 μm in this order and pressure bonding for 90 minutes under conditions of a pressure of 2.0 MPa and a temperature of 200 ° C. I got a plate. Next, the multilayer wiring board was cut out to 50 × 50 mm, and the copper foil was removed by etching. Then, it was treated under the following conditions using a desmear solution manufactured by ROHM AND HAAS, and the weight per area from the weight change before and after the treatment. The amount of reduction was calculated.
MLB conditioner 211: temperature; 80 ° C., treatment time: 5 minutes MLB promoter 213: temperature; 80 ° C., treatment time: 10 minutes MLB neutralizer 216-2: temperature; 40 ° C., treatment time: 5 minutes

(Synthesis Example 1: Production of thermosetting resin composition)
Bisphenol A type cyanate resin as a compound having 1000 g of toluene and at least two cyanate groups in one molecule in a reaction vessel with a capacity of 3 liters which can be heated and cooled with a thermometer, a stirrer and a reflux condenser. (Lonza Japan Co., Ltd .; trade name Arocy B-10): 1000 g was added, heated while stirring, and after reaching 120 ° C., 0.01 g of an 8 mass% mineral spirit solution of zinc naphthenate was added, After refluxing at about 115 to 125 ° C. for 4 hours, the mixture was cooled to room temperature (25 ° C.) to obtain a thermosetting resin composition solution.

The solution before the temperature increase of the solution of the thermosetting resin composition and the solution after the reflux reaction and cooling were taken out little by little, and GPC measurement (polystyrene conversion, eluent: tetrahydrofuran) was performed for each. Compare the peak area of the bisphenol A-type cyanate resin that has a retention time of about 12.4 minutes between the solution before the reaction and the solution after the reaction, and compare the peak area of the solution after the reaction with the peak area of the solution before the reaction. The disappearance rate of the peak area was calculated. As a result, the disappearance rate of the peak area in the solution after the reaction was 65%. Therefore, the reaction rate of the compound having at least two cyanate groups in one molecule in the thermosetting resin composition was 65 mol%. Further, around 2270 cm ^-1 due to the triazine ring, 1560 cm around ^-1, and 1380 cm ^-1 can strong peaks confirmed the vicinity, was confirmed to include a resin having a cyanato group in the thermosetting resin composition.

<Inner layer board>
A resin composition was prepared by blending 1000 g of the thermosetting resin composition solution of Synthesis Example 1 and 800 g of silica and preparing a resin composition such that the resin content of the glass cloth having a thickness of 100 μm was 63% by mass. Was impregnated. This was dried by heating at 160 ° C. for 5 minutes to obtain a prepreg having a resin volume fraction of 72%.
Subsequently, four prepregs are stacked to form a laminate, and an electrolytic copper foil having a thickness of 18 μm is disposed on one surface and the other surface of the laminate, and the pressure is 2.45 MPa and the temperature is 230 ° C. A laminate was obtained by pressure bonding for 90 minutes. Thereafter, a lattice-like pattern was prepared so that the remaining copper ratio was 30%, and an inner layer plate in which the circuit was processed was obtained.

[Production Examples 1 to 3]
A solution of the thermosetting resin composition and silica were blended at a ratio shown in Table 1, and impregnated into a glass cloth having a thickness of 40 μm. This was dried by heating at 160 ° C. for 3 minutes to obtain prepregs 1 to 3 having a resin volume fraction of 85%.

[Examples 1 to 3]
50 prepregs (500 mm × 500 mm) obtained according to the above production examples 1 to 3 were stacked immediately after preparation, and sheet-like desiccant (S-PES-30-111J, Sasaki Chemicals, Inc., trade name, maximum moisture absorption) (Amount 1.4 g / m ² , 600 mm × 600 mm, thickness 40 μm), packed in a plastic bag, and stored for 2 months at 25 ° C. and 60% relative humidity of the outside air. Desmear resistance was evaluated using the stored prepreg. The results are shown in Table 2.

[Reference Examples 1-3]
Using the prepreg obtained in the above Production Examples 1 to 3, desmear resistance was evaluated immediately after production. The results are shown in Table 3.

[Comparative Examples 1-3]
Fifty sheets of the prepregs obtained in the above Production Examples 1 to 3 were stacked immediately after preparation, packed in a plastic bag, and stored for 2 months at 25 ° C. and a relative humidity of 60% in the outside air. Desmear resistance was evaluated using the stored prepreg. The results are shown in Table 4.

  From the results of Tables 2 to 4, it can be seen that the use of a sheet-like desiccant can suppress a decrease in desmear resistance.

  According to the prepreg storage method using the sheet-like desiccant of the present invention, it has high desmear resistance and is useful for preserving prepregs used in the production of printed wiring boards for electronic devices.

Claims (20)

  A method for preserving a prepreg, comprising storing a laminate in which at least one sheet-like desiccant and at least one prepreg formed by impregnating a glass cloth with a resin composition are stored.   The method for preserving a prepreg according to claim 1, wherein the sheet-like desiccant is disposed on at least both outermost surfaces of the laminate. The method for preserving a prepreg according to claim 1 or 2, wherein a maximum moisture absorption amount of the sheet-like desiccant is 0.5 g / m ² or more.   The method for preserving a prepreg according to any one of claims 1 to 3, wherein the ratio of the area of one side of the sheet-like desiccant to the area of one side of the prepreg is 0.8 or more.   The method for preserving a prepreg according to any one of claims 1 to 4, wherein the thickness of the sheet-like desiccant is 10 to 500 µm.   The prepreg storage method according to any one of claims 1 to 5, wherein the sheet-like desiccant comprises a desiccant resin composition in which a desiccant is kneaded with a thermoplastic resin.   The method for preserving a prepreg according to claim 1, wherein the resin composition of the prepreg contains a resin having a cyanato group.   The method for preserving a prepreg according to claim 1, wherein the resin composition of the prepreg further contains an inorganic filler.   The method for preserving a prepreg according to any one of claims 1 to 8, wherein the laminate is stored in a package.   A laminate in which at least one sheet-like desiccant and at least one prepreg formed by impregnating a glass cloth with a resin composition are stacked.   The laminate according to claim 10, wherein the sheet-like desiccant is disposed on both outermost surfaces of the laminate. The laminate according to claim 10 or 11, wherein a maximum moisture absorption amount of the sheet-like desiccant is 0.5 g / m ² or more.   The laminate according to any one of claims 10 to 12, wherein a ratio of the area of one side of the sheet-like desiccant to the area of one side of the prepreg is 0.8 or more.   The laminate according to any one of claims 10 to 13, wherein the thickness of the sheet-like desiccant is 10 to 500 µm.   The laminate according to any one of claims 10 to 14, wherein the resin composition of the prepreg contains a resin having a cyanate group.   The laminate according to any one of claims 10 to 15, wherein the resin composition of the prepreg further contains an inorganic filler.   It has a laminated body in any one of Claims 10-16, and the package which stored this laminated body, The laminated body package characterized by the above-mentioned.   The said package body has a sealing function, The laminated body package of Claim 17 characterized by the above-mentioned.   The said package body has a moisture absorption function, The laminated body package of Claim 17 or 18 characterized by the above-mentioned.   The said package is the aluminum vapor deposition process, The laminated body package in any one of Claims 17-19 characterized by the above-mentioned.