阅读说明：本技术 一种薄膜及其制备方法和电容器 (Film, preparation method thereof and capacitor ) 是由 许靖晗 卢锋 李医 罗进文 肖鄂 万卫平 杨红军 于 2021-06-09 设计创作，主要内容包括：本发明公开了一种薄膜及其制备方法和电容器,包括依次设置的介电膜层、金属层及硅油保护层。其能有效提高电容器在极端环境中的使用寿命,以增加电子产品的安全性能和使用寿命。(The invention discloses a film, a preparation method thereof and a capacitor. The capacitor can effectively prolong the service life of the capacitor in an extreme environment so as to increase the safety performance and the service life of an electronic product.)

1. A film, characterized by: comprises a dielectric film layer, a metal layer and a silicone oil protective layer which are arranged in sequence.

2. A film according to claim 1, wherein: and a blank area is arranged at one end of the dielectric film layer, and the silicone oil protective layer is arranged on the surfaces of the metal layer and the blank area.

3. A film according to claim 1, wherein: the water contact angle of the silicone oil protective layer is 70-105 degrees.

4. A film according to claim 1, wherein: the silicone oil protective layer is composed of polysiloxane.

5. A film according to claim 4, wherein: the water contact angle of the silicone oil protective layer is calculated by the following formula:

wherein n is a water contact angle, Δ h is a volume consumed by the silicone oil, ρ is a density of the silicone oil, s is a number of silicon atoms contained in a single polysiloxane molecule, Mn is an average molecular weight of the constituent polysiloxane, L is a roll film length, and D is a roll film width.

6. A film according to claim 5, wherein: the density rho of the silicone oil is 0.5-1g/cm³The number s of silicon atoms contained in a single polysiloxane molecule is between 1 and 100, and the average molecular weight Mn of the polysiloxane is between 100 and 5000.

7. A film according to claim 1, wherein: the dielectric film layer is composed of one of an oriented polypropylene film, a polyethylene terephthalate film, a polyimide film and a polystyrene film.

8. A film according to claim 1, wherein: the metal layer is composed of at least one of aluminum, zinc, magnesium, silver, iron, nickel and gold.

9. A method of producing a film according to any one of claims 1 to 8, characterized in that: the method comprises the following steps:

(1) depositing a layer of metal on the surface of the dielectric film layer to form a metal layer;

(2) depositing silicon oil vapor on the surface of the metal layer to form a silicon oil protective layer;

(3) and carrying out plasma curing treatment on the silicone oil protective layer to obtain the silicone oil protective layer.

10. A capacitor comprising the film according to any one of claims 1 to 8.

Technical Field

The invention belongs to the technical field of film capacitors, and particularly relates to a film, a preparation method thereof and a capacitor.

Background

In recent years, with the improvement of the safety performance requirement of electronic products, the market has higher and higher requirements on the service life of the products under extreme environments, and particularly has higher requirements on the performance of thin film capacitors. A film in a common film capacitor comprises a metal layer, and when the film is used in an environment with high temperature and humidity, the metal layer is easy to oxidize, so that the capacity of the capacitor is attenuated, and the service life of a product is influenced. In order to reduce the capacity fade, manufacturers typically choose to increase the thickness of the metal layer to prevent the complete disappearance of the active area of the metal layer. However, since the increase in the thickness of the metal layer damages the dielectric thin film and lowers the withstand voltage of the capacitor, it is urgently required to develop a thin film which is not easily oxidized in a high-temperature and high-humidity environment so as to prevent the capacity attenuation of the capacitor from being greatly reduced and to secure the service life of the thin film capacitor.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a film, a preparation method thereof and a capacitor, which can effectively prolong the service life of the capacitor in an extreme environment so as to increase the safety performance and the service life of an electronic product.

The technical purpose of the invention is realized by the following technical scheme:

a film comprises a dielectric film layer, a metal layer and a silicone oil protective layer which are arranged in sequence.

Preferably, a blank area is arranged at one end of the dielectric film layer, and the silicone oil protective layer is arranged on the surfaces of the metal layer and the blank area.

Preferably, the water contact angle of the silicone oil protective layer is 70-105 degrees.

Further preferably, the water contact angle of the silicone oil protective layer is 90-105 °.

Preferably, the silicone oil protective layer is composed of polysiloxane.

Preferably, theThe water contact angle of the silicon oil protective layer is calculated by the following formula:wherein n is a water contact angle, Δ h is a volume consumed by the silicone oil, ρ is a density of the silicone oil, s is a number of silicon atoms contained in a single polysiloxane molecule, Mn is an average molecular weight of the constituent polysiloxane, L is a roll film length, and D is a roll film width.

Preferably, the density rho of the silicone oil is 0.5-1g/cm³The number s of silicon atoms contained in a single polysiloxane molecule is between 1 and 100, and the average molecular weight Mn of the polysiloxane is between 100 and 5000.

Preferably, the dielectric film layer is formed of one of an oriented polypropylene film, a polyethylene terephthalate film, a polyimide film, and a polystyrene film.

Further preferably, the dielectric film layer is composed of an oriented polypropylene film.

Further preferably, the dielectric film layer is composed of a biaxially oriented polypropylene film.

Preferably, the metal layer is made of at least one of aluminum, zinc, magnesium, silver, iron, nickel, and gold.

Another object of the present invention is to provide a method for preparing the above film, comprising:

a method for preparing a thin film as described above, comprising the steps of:

(1) depositing a layer of metal on the surface of the dielectric film layer to form a metal layer;

(2) depositing silicon oil vapor on the surface of the metal layer to form a silicon oil protective layer;

(3) and carrying out plasma curing treatment on the silicone oil protective layer to obtain the silicone oil protective layer.

It is another object of the present invention to provide a capacitor comprising a film as described above.

Preferably, the preparation method of the capacitor comprises the following steps:

(1) using two films to carry out staggered winding to manufacture a capacitor core;

(2) flattening the round core into a flat shape;

(3) carrying out gold spraying treatment on the end surface of the flattened core to form a conductive gold spraying layer;

(4) welding wires on two sides of the metal spraying layer to form pins;

(5) and (4) placing the core subjected to wire welding into a plastic shell, pouring epoxy resin, and curing to obtain the core.

The invention has the beneficial effects that:

the film of the invention has excellent oxidation resistance, particularly when the water contact angle of the silicon oil protective layer is 70-105 degrees, the oxidation resistance is enhanced along with the increase of the water contact angle, and when the water contact angle of the silicon oil protective layer is 90-105 degrees, the oxidation resistance is optimal.

The film capacitor provided by the invention has excellent high-temperature and high-humidity resistance, when the water contact angle of the silicone oil protective layer is larger than 70 degrees, the capacity attenuation of the capacitor is gradually reduced, and the high-temperature and high-humidity resistance of the capacitor meets the requirement. When the water contact angle is between 90 degrees and 105 degrees, the capacitor has extremely low capacity attenuation, and the capacitor has the best high-temperature and high-humidity resistance.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic representation of a film of the present invention;

FIG. 2 is a schematic diagram of a capacitor according to the present invention.

Reference numerals:

100. a dielectric film layer; 200. a metal layer; 300. a silicone oil protective layer; 400. spraying a gold layer; 500. a pin; 600. a housing.

Detailed Description

The present invention will be further described with reference to the following specific examples.

Examples 1 to 21:

as shown in fig. 1, the films of examples 1 to 21 include a dielectric film layer 100, a metal layer 200, and a silicone oil protection layer 300, which are sequentially disposed, wherein a blank region is disposed at one end of the dielectric film layer 100, and the silicone oil protection layer 300 is disposed on the metal layer 200 and the blank region, wherein the dielectric film layer 100 is made of a biaxially oriented polypropylene film.

The preparation method of the film comprises the following steps:

(1) depositing a layer of aluminum or zinc-aluminum alloy on the surface of the dielectric film layer 100 to form a metal layer 200, and meanwhile, coating shielding oil on one end of the dielectric film layer 100 to shield deposition of aluminum metal and form a blank region;

(2) depositing silicon oil vapor on the metal layer 200 and one side surface of the blank area to form a silicon oil protective layer 300;

(4) and carrying out plasma oxidation curing on the silicone oil protective layer 300 to obtain the silicone oil protective layer.

Wherein in order to ensure that the silicone oil is completely cured, the strength of the plasma treatment needs to be defined, and the treatment strength formula is as follows:

E＝P/(v×D)

wherein E is the plasma processing intensity, P is the output power of the plasma equipment, v is the ion velocity, and D is the dielectric film width. In the production of the film of the present invention, the plasma treatment intensity needs to be more than 12.5.

Meanwhile, the sheet resistance of the metal layer 200 region of the examples 1 to 21 was 14. + -. 2. omega./cm²。

Further, the silicone oil protective layer was composed of polysiloxane, and the water contact angle of the silicone oil protective layer was calculated by the following formula

Obtaining:

wherein n is a water contact angle, deltah is a volume consumed by the silicone oil, rho is a density of the silicone oil, s is a number of silicon atoms contained in a single polysiloxane molecule, Mn is an average molecular weight of the component polysiloxane, L is a roll film length, D is a roll film width, and the density rho of the silicone oil is 0.5-1g/cm³Wherein the number s of silicon atoms contained in a single polysiloxane molecule is between 1 and 100, the average molecular weight Mn of the polysiloxane is between 100-The deviation between the quantity values is less than 2 °.

Examples 1 to 21 use three types of silicone oils, but the silicone oils used for the film of the present invention are not limited to the three types described in the examples. The data relating to the water contact angle of the film are shown in table 1.

Table 1: water contact angles of films of examples 1-21:

as can be seen from Table 1, the deviation between the water contact angle data calculated according to the above formula and the actual measurement value of the contact angle measuring instrument is not more than + -2 degrees, which shows that the empirical formula of the present invention can be used for the production design of the thin film of the present invention.

As shown in fig. 2, the capacitors of examples 1-21, respectively, correspond to the films comprising examples 1-21, and the method of making the capacitors comprises the steps of:

(1) using two films to carry out staggered winding to manufacture a capacitor core;

(2) flattening the round core into a flat shape;

(3) carrying out gold spraying treatment on the end surface of the flattened core to form a conductive gold spraying layer 400;

(4) welding wires on two sides of the gold spraying layer 400 to form a pin 500;

(5) and (3) placing the core with the welded wire into a plastic shell 600, pouring epoxy resin, and curing to obtain the core.

Test example:

the films of examples 1 to 21 were each subjected to a saturated vapor test (PCT) under conditions in which the film was left to stand at 105 ℃, 100% humidity, and 1.3atm for 30min, and then the oxidation area measurement and the automatic calculation of the oxidation ratio were performed using a super-depth of field three-dimensional microscope system to obtain the oxidation rate of the film surface.

Meanwhile, the capacitors of examples 1 to 21 were tested in a durability test under normal pressure at 85 ℃ and 85% humidity, and after the capacitor was energized, the capacitor was tested under a 310V AC voltage for 1000h, and the capacitance decay rate of the capacitor was counted.

The oxidation rate of the film surface of examples 1 to 21 and the capacity fade rate of the capacitor of examples 1 to 21 are shown in Table 2.

Table 2: results of Performance testing

Examples	Water contact angle measurement	Oxidation rate of film	Rate of capacity fade of capacitor
				1	61.98	20.67％	15.96％
2	66.74	22.35％	15.87％
				3	69.53	21.46％	16.32％
4	71.32	15.33％	14.74％
				5	72.88	13.79％	14.69％
6	76.94	11.38％	13.66％
				7	85.96	6.32％	9.96％
8	89.67	4.41％	8.88％
				9	91.38	4.26％	5.61％
10	92.79	3.92％	5.85％
				11	94.86	3.85％	4.04％
12	96.05	3.69％	3.99％
				13	94.31	3.17％	2.77％
14	97.43	3.06％	2.91％
				15	99.85	2.69％	2.06％
16	98.35	3.07％	1.94％
				17	102.79	2.77％	1.85％
18	103.66	2.65％	1.73％
				19	100.94	2.98％	1.66％
20	106.38	2.64％	1.14％
				21	105.42	2.54％	1.12％

As can be seen from Table 2, through the test of saturated steam experiment, when the water contact angle of the surface of the film of the present application is 70-105 degrees, the oxidation rate thereof decreases with the increase of the water contact angle, and when the water contact angle of the surface of the film is 90-105 degrees, the oxidation area of the film after the PCT test is less than 6%, and the oxidation resistance of the film reaches the best state.

Meanwhile, when the water contact angle is less than 70 degrees, the capacitor has larger capacity attenuation after being tested, which shows that the capacitor has poor high temperature and high humidity resistance, when the water contact angle is more than 70 degrees, the capacity attenuation rate of the capacitor is gradually reduced, the high temperature and high humidity resistance of the capacitor meets the requirement, when the water contact angle is between 90 degrees and 105 degrees, the capacity attenuation of the capacitor is smaller, and the high temperature and high humidity resistance of the capacitor achieves the best effect.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.