FOIL FOR ADHESIONING

Abstract

Adhesive film, comprehensive: an embossed surface, wherein the embossed surface has an A2 / A1 value of 1 or less; and a region of increasing thickness, wherein the region of increasing thickness has a first end and a second end, and the thickness of the first end differs from the thickness of the second end; where a wedge angle (θ) is calculated according to equation 1 below and the wedge angle of the region with increasing thickness is 0.01 to 0.04°, where the embossed surface has an Sz value of 30 to 90 µm, where the ratio of Ha to w is between 0.0002 and 0.0015, and where the A2 value is 0.6 or less, θ = arc tan ( H b − H aw ) where in equation 1 Hb is a thickness of the thicker end from the first end to the second end of the region with increasing thickness, Ha is a thickness of the thinner end from the first end to the second end of the region with increasing thickness, and w is the width from the first end to the second end of the region with increasing thickness.

Description

TECHNICAL FIELD [CROSS-REFERENCE TO RELATED APPLICATIONS]

[0001] This application claims the priorities of Korean patent application No. 10-2019-0097413, filed on August 9, 2019; Korean patent application No. 10-2019-0103615, filed on August 23, 2019; Korean patent application No. 10-2020-0008459, filed on January 22, 2020; Korean patent application No. 10-2019-0105222, filed on August 27, 2019; and Korean patent application No. 10-2019-0145153, filed with the Korean Intellectual Property Office on November 13, 2019. BACKGROUND

[0002] Polyvinyl acetal is used as an interlayer (film for laminated glass) in laminated glass (safety glass) or translucent laminates. Laminated glass is primarily used for windows in buildings, cladding, and car windows. Due to its properties, such as preventing shattering upon breakage and its resistance to impacts of a certain magnitude, it can provide stability to minimize damage or injury to objects or people within it.

[0003] A film for adhesive application can be a wedge-shaped film whose cross-section has a uniform wedge angle to prevent the formation of a double image when used as a head-up display film.

[0004] A film for bonding has several tiny embossings formed in the surface to improve the property of preventing blockage between the intermediate layers, improving processability when overlapping a glass plate with an intermediate layer (gliding ability of a glass plate as processability) and improving venting stability when processing for lamination with a glass plate.

[0005] When an embossed film is used for bonding during lamination, there is a possibility that the embossed dots on both surfaces of the film will create an interference pattern or bubble, which can impair visibility. Furthermore, reduced processability can occur if glare develops. (Related state of the art)

[0006] Korean registered patent application no. KR 10-1376061 B1

[0007] Japanese Patent Publication No. JP 2001-220183 A US 2018 / 022058 A1, and US 2018 / 272661 A1. US 2018 / 022058 A1 describes an interlayer film for laminated glass that is easily removable without self-adherence even after storage in a stacked state, laminated glass manufactured using the interlayer film, and a method for manufacturing the interlayer film. Furthermore, US 2018 / 022058 A1 relates to an interlayer film for laminated glass that has a large number of indentations on at least one surface, wherein the at least one surface with the indentations has an arithmetic mean height Sa of 200 nm or more, measured according to ISO 25178. US 2018 / 272661 A1 describes an interlayer film for laminated glass that prevents air bubbles from remaining between a laminated glass element and the interlayer film during the manufacturing of laminated glass. The interlayer film for laminated glass contains a thermoplastic resin and has a section in which the increase in thickness from end to end is increased in the area where the thickness increases; a section in which the increase in thickness from end to end is decreased in the area where the thickness increases; a section in which the wedge angle in one direction from end to end is increased in the area where the cross-sectional shape has a wedge shape in the thickness direction; or a section in which the wedge angle in one direction from end to end in the area where the thickness increases is decreased.in which the cross-sectional shape in the thickness direction has a wedge-shaped form, is reduced, and the ten-point average roughness Rz of the surface at a central position of the section where the thickness is increased, the section where the thickness is decreased, the section where the wedge angle is increased, or the section where the wedge angle is decreased, is 20 µm or more. DETAILED DESCRIPTION OF THE INVENTIONAL TECHNICAL TASK

[0008] The purpose of the embodiment is to provide a film for bonding that has improved venting properties, edge sealing properties and the like, and can suppress the occurrence of a ghost image in a head-up display. TECHNICAL SOLUTION

[0009] The invention is defined by the claims. In a general aspect, a film for bonding according to one embodiment comprises an embossed surface, and the embossed surface has an A2 / A1 value of 1 or less.

[0010] The adhesive film has a region of increasing thickness, wherein the region of increasing thickness has a first end and a second end, and the thickness of the first end differs from the thickness of the second end; where a wedge angle (0) is calculated according to equation 1 below and the wedge angle of the area with increasing thickness is 0.01 to 0.04°, θ=arctan(Hb−Haw) where in equation 1 Hb is the thickness of the thicker end from the first end to the second end of the region with increasing thickness, Ha is the thickness of the thinner end from the first end to the second end of the region with increasing thickness, and w is the width from the first end to the second end of the region with increasing thickness. An Sz value of the embossed surface is 30 µm or more and 90 µm or less.

[0011] The Sz value of the embossed surface can be 40 µm or more and 80 µm or less.

[0012] The A1 value can be 0.5 or higher.

[0013] The A2 value is 0.6 or less.

[0014] The film to be bonded can be a single-layer film or a composite film with two or more layers.

[0015] The film to be bonded may contain a polyvinyl acetal resin.

[0016] A general aspect is that a film for bonding according to one embodiment has an embossed surface with a regular or irregular pattern, wherein the embossed surface has a Mr1 value and a Mr2 value, where a rev_Mr2 value is a value resulting from subtracting the Mr2 value from 100%, and where the embossed surface has a Mr1 value that is equal to or greater than the rev_Mr2 value, and where the A2 value is 0.6 or less.

[0017] A rev_Mr2 value is a value that results from subtracting the Mr2 value from 100%.

[0018] A peak valley distribution (Spv) is calculated according to Equation 1, and the peak valley distribution of the imprinted surface can be 0% or more and 25% or less. Spv=Mr1−rev_Mr2 where in equation 1 the Spv value is the peak-trough distribution and the rev_Mr2 value is a value that results from subtracting the Mr2 value from 100%.

[0019] The Mr1 value can be 10% or more.

[0020] The Sz value of the embossed surface can be 30 µm or more and 90 µm or less.

[0021] The film to be bonded can be a single-layer film or a composite film with two or more layers.

[0022] The film to be bonded may contain a polyvinyl acetal resin.

[0023] The film to be bonded can have a wedge shape in part or in its entire cross-section. BENEFICIAL EFFECTS

[0024] A bonding film can provide a bonding film that improves the venting stability during the formation of a translucent laminate, the edge sealing properties and the like by controlling the properties of a surface on which embossing is formed. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 and Fig. Figure 2 shows cross-sectional views schematically illustrating a film for bonding according to one embodiment. Fig. 3 is a cross-sectional view that schematically shows films for bonding with a soundproofing layer according to another embodiment in a), b) and c). Fig. Figure 4 is a conceptual diagram showing an embossing roller used as a comparative example in a film manufacturing process for bonding. Fig.Figure 5 is a conceptual diagram illustrating a method for preparing a surface embossing in the manufacture of a film for bonding according to one embodiment. DETAILED DESCRIPTION OF EXAMPLE EXECUTION FORMS

[0025] Exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying drawings, so that they can be easily implemented by those skilled in the art in the field to which the present invention relates. However, these exemplary embodiments can be implemented in many different forms and are not to be understood as being limited to the embodiments presented here. The same reference numerals denote the same elements throughout the entire description.

[0026] In the present application, terms such as "approximately", "essentially", etc., are used to denote values ​​that approximate the value when a tolerance is specified that is significant for the manufacture and the substance. Additionally, these terms are used to facilitate understanding of the illustrative examples and to prevent the presented content, which refers to an exact or absolute number, from being misused by inexperienced persons.

[0027] Throughout the application, the expression ‘combination(s) thereof’ contained in a Markush expression refers to one or more mixtures or combinations selected from the group of constituents mentioned in the Markush expression; that is, it refers to the one or more constituents selected from the group of constituents that are included.

[0028] Throughout the entire application, the term “A and / or B” means “A or B or A and B”.

[0029] This application uses terms such as "first", "second", "A" or "B" to distinguish between identical terms.

[0030] In this application, “B is placed on A” means that B is placed in direct contact with A or placed above A, with another layer or structure possibly in between, and should therefore not be interpreted as limiting this expression to B being placed in direct contact with A.

[0031] In this application, the singular form includes the plural form, unless it is obvious from the context that this is not the case.

[0032] In this application, the size of individual components of a drawing may be exaggerated and differ from the size to be used in practice.

[0033] In this application, the amount of the hydroxyl group was determined by measuring the amount of the ethylene group in combination with the hydroxyl group of the polyvinyl acetal resin in accordance with a method based on JIS K6728.

[0034] In this application, A1, A2, Mr1, Mr2, Sk, Spk, Svk and Sz are values ​​that are evaluated according to ISO_25178.

[0035] A1, A2, Mr1, Mr2, Sk, Spk, Svk and S*vk are values ​​derived from a diagram for the surface material ratio (Abbott-Firestone curve) and can be measured by a 3D roughness measurement.

[0036] An area-material ratio curve is a curve that represents the height of an object's surface contour in a mathematical cumulative probability density function and is a method for specifying the surface features of an object.

[0037] An area-material ratio curve uses an equivalent straight line. This equivalent straight line encompasses 40% of the measured points on the curve. A 40% segment of the total area (x-axis) is arbitrarily inserted into the curve, and connecting the two ends of this segment yields a line with minimal slope. Using this equivalent straight line, values ​​for surface features such as A1, A2, Mr1, Mr2, Sk, Spk, Svk, and S*vk can be derived.

[0038] A film for bonding has a surface embossing, such as a regular raised pattern or a fusion fracture in the surface, to prevent unnecessary blocking between surfaces during winding and to achieve venting performance when laminated with a translucent layer like glass. However, if only the venting property is considered during film manufacturing, the film's optical properties may deteriorate, or the edge sealing may be inadequate. Conversely, if only the edge sealing property is considered during film manufacturing, the film's optical properties may deteriorate due to problems such as the formation of bubbles.

[0039] A pre-lamination is generally carried out at a lower temperature than a lamination, and in the case of a process where a squeeze roller is used rather than a pre-bonding process using a vacuum ring, the temperature at which the glass is picked up is relatively lower, and the pre-lamination is generally carried out at about 70 °C or less, relative to the temperature of the glass surface.

[0040] To achieve a stable bond when pre-lamination is carried out at a low temperature, it is common to achieve processability by simply reducing the surface roughness of the embossed pattern, but this is also one of the causes of lower venting performance.

[0041] Simultaneously, the film to be bonded can be laminated onto a translucent surface such as a glass plate to form a translucent laminate. This embodiment can provide a user (driver) with a head-up display by projecting an image onto the translucent laminate. However, the image projected onto the translucent laminate can form a double image upon transmission or reflection in a translucent surface such as glass or the bonding film, and the image may be perceived as a ghost image, or the image sharpness may be reduced for the user. To prevent such a phenomenon, a wedge-shaped adhesive film is used for the head-up display.

[0042] The inventors have confirmed that by controlling features such as A1, A2, Mr1, Mr2, Sk, Spk, Svk, and S*vk, and similar values ​​of the embossed surface, compromises can be achieved in both ventilation performance and edge sealing. They have also confirmed that by controlling the wedge angle of the film used to bond the translucent laminate, the ghosting effect of the head-up display image can be suppressed. They then present the embodiment.

[0043] One embodiment is described in detail below.

[0044] A1, A2, Mr1, Mr2, Sz, Sk, Spk and Svk are evaluated according to ISO_25178.

[0045] A1, A2, Mr1, Mr2, Sk, Spk, Svk and S*vk are values ​​derived from a diagram for the area-to-material ratio (Abbott-Firestone curve). A1, A2, Mr1, Mr2, Sk, Spk, Svk and S*vk can be the values ​​measured and calculated during a 3D roughness measurement.

[0046] The measurement of 3D roughness can be evaluated by an average value of values ​​taken over a total area of ​​1,000,000 µm. 2 or more were measured. When measuring with a three-dimensional optical profiling device or a 3D laser measuring microscope, the 3D roughness can be measured five times or more in different positions, each time covering an area of ​​340,000 µm. 2or more, and an average of the values, excluding the maximum and minimum values, can be used as a measurement of the three-dimensional roughness. When using a 3D laser measuring microscope, 3D roughness can be measured by stitching together adjacent images using a stitching function, and the measurement using such a stitching function can also be evaluated by averaging values ​​obtained over a total range of 1,000,000 µm. 2 or more were measured.

[0047] For example, the Contour GT model can be used as an optical 3D microscope from BRUKER, and the 3D roughness can be determined by measurement in VSI mode (Vertical scanning Interferometry) (see below).

[0048] The embossed surface may have minor irregularities.

[0049] The fine irregularities can occur at the peak and valley of the embossed pattern.

[0050] In the production of the embossing, the embossed side can have the properties described above by applying a process for further processing a fine pattern on one side of the film for bonding, or by additionally processing a fine pattern on the surface of a die or roller that transfers the embossing. In particular, the fine pattern can be incorporated on the surface of the film to be bonded by further processing the fine pattern on a die or roller to transfer the embossing onto the film to be bonded, and the pattern is transferred to the surface of the film to be bonded by means of the die or roller. For example, fine patterns can be further processed by fine sandblasting on a die or roller. However, the method of further processing the fine pattern is not limited to this.

[0051] Fig. 1 and Fig.Figure 2 shows cross-sectional views schematically illustrating a film for bonding according to one embodiment. Fig. Figure 3 is a cross-sectional view schematically showing films for bonding with a soundproofing layer according to another embodiment in a), b), and c). The following sections refer to the Fig. , Fig. until Fig. The embodiments are described in more detail.

[0052] A film for bonding 100 has an embossed surface whose A2 / A1 value is 1 or less, and includes an area A that increases the thickness.

[0053] The thickening region A has two ends, which in cross-section are one end and the other end, and the thickness of one end differs from the thickness of the other end.

[0054] The thickness of the region with increasing thickness A can increase from one end to the other. The thickness can increase at a constant rate across the entire region with increasing thickness A. The thickness can increase at a gradually increasing rate across the area with increasing thickness A. The thickness can increase at a rate that gradually decreases across the entire area with increasing thickness A.

[0055] The thickness of the region with increasing thickness A can decrease from one end to the other. The thickness can decrease at a constant rate across the entire region A with increasing thickness. The thickness can decrease at a gradually increasing rate across the area A with increasing thickness. The increase in thickness can be reduced at a gradually decreasing rate across the entire area A with increasing thickness.

[0056] Area A, which increases the thickness, has angles of transmitted or reflected light adjusted by the ends with their differing thicknesses. Therefore, a translucent laminate prevents the formation of a double image when light from the head-up display system's light source is emitted.

[0057] The thickening region A has a wedge angle (0), the wedge angle (0) is calculated by the following equation 3, and the wedge angle of the thickening region A can be 0.01 to 0.04°. θ=arctan(Hb−Haw) where in equation 3, The Hb is a thickness of the thicker part of one end and the thicker part of the other end of the increasing region A. Ha is the thickness of the thinner end of the region A, which increases in thickness at the other end. w is the width from one end to the other end of the region A where the thickness increases.

[0058] The Hb value and the Ha value, the mean thickness and the average thickness, can be measured with a Mitsubishi ® 547-401 thickness gauge, but are not limited to this.

[0059] The wedge angle of the thickening area A can be 0.01° or more. The wedge angle of the thickening area A can be 0.04° or less. The wedge angle of the thickening area A can be 0.011° or more. The wedge angle of the thickening area A can be 0.03° or less. The film for bonding with the wedge angle can effectively suppress the formation of double images when used as an intermediate film for a head-up display.

[0060] The ratio of Hb to w can be 0.001 or more and 0.002 or less.

[0061] The ratio of Ha to w can be 0.0002 or more and 0.0015 or less.

[0062] A specific measurement procedure for the Ha value and the Hb value is the same as the procedure described above.

[0063] Specifically, the Ha value can be 0.38 mm or higher. Furthermore, the Ha value can be 0.40 mm or higher. If the Ha value is greater than 0.38 mm, the film to be bonded can exhibit stable puncture resistance.

[0064] The ratio of Hb to W can be 0.001 or more and 0.002 or less. Furthermore, the ratio of Hb to W can be 0.001 or more and 0.0018 or less. If the W to Hb ratio is within the above range, it is possible to provide an adhesive film that exhibits excellent impact and penetration resistance and prevents double vision.

[0065] The ratio of Ha to W can be 0.0002 or more and 0.0015 or less. Furthermore, the ratio of Ha to W can be 0.0003 or more and 0.0013 or less. If the ratio of Ha to W is within the above range, it is possible to provide a bonding film that simultaneously exhibits penetration resistance and double-image prevention.

[0066] The thickness-increasing area A of the film to be bonded can be applied to part or all of the film to be bonded 100.

[0067] If the area A that increases the thickness is located in a part of the film for bonding 100, the area A that increases the thickness can be located on the side of the film for bonding 100.

[0068] The film for bonding 100 can have one, two, or more thickness-increasing areas A.

[0069] An adhesive film 100 has an embossed surface with a regular or irregular pattern. The embossed surface has a Mr1 value and a Mr2 value. A rev_Mr2 value is a value resulting from subtracting the Mr2 value from 100%. The embossed surface has an Mr1 value that is equal to or greater than the rev_Mr2 value. The film for bonding A includes an area A that increases the thickness.

[0070] The description of the thickening area A is omitted here, as it overlaps with the content described above.

[0071] The film for bonding 100 can be a single-layer film or a composite film with two or more layers.

[0072] The adhesive film 100 can consist of a polyvinyl acetal resin and may contain a polyvinyl acetal resin and a plasticizer.

[0073] In particular, the film to be bonded can contain a polyvinyl acetal resin in an amount of 60 to 76 wt%, 70 to 76 wt%, or 71 to 74 wt%. When the polyvinyl acetal resin is present in such a range, a film to be bonded can achieve a relatively high tensile strength and a high modulus.

[0074] The polyvinyl acetal resin may contain an acetyl group in an amount of less than 2 wt%, and in particular in an amount of 0.001 wt% or more and less than 1.5 wt%. The polyvinyl acetal resin may contain a hydroxyl group in an amount of 15 wt% or more, 16 wt% or more, or 19 wt% or more. Polyvinyl acetal resin applied to the first layer may also contain a hydroxyl group in an amount of 30 wt% or less.

[0075] When a polyvinyl acetal resin with such adhesive properties is applied to the film, the film can be excellently bonded to a material such as glass and exhibit mechanical properties such as good puncture resistance.

[0076] The polyvinyl acetal resin can be obtained by acetalizing a polyvinyl alcohol with a degree of polymerization of 1,600 to 3,000 with aldehyde, or it can be obtained by acetalizing a polyvinyl alcohol with a degree of polymerization of 1,700 to 2,500 with aldehyde. Using such a polyvinyl acetal can significantly improve the mechanical properties, such as the puncture resistance of the film.

[0077] Polyvinyl acetal resin can be synthesized from polyvinyl alcohol and an aldehyde, the type of aldehyde being unlimited. In particular, the aldehyde can be from the group consisting of n-butylaldehyde, isobutylaldehyde, n-valericaldehyde, 2-ethylbutylaldehyde, n-hexylaldehyde, and their mixed resins. If n-butylaldehyde is used as the aldehyde, the resulting polyvinyl acetal resin can have a refractive index that differs only slightly from that of glass and exhibit excellent adhesion to glass and similar materials.

[0078] The film to be bonded can contain the plasticizer in an amount of 24 to 40% by weight, 24 to 30% by weight, or 26 to 29% by weight. A film containing the plasticizer in such a range is preferable because a laminated film can achieve adequate adhesive strength and impact resistance for bonding.

[0079] In particular, the plasticizer may be any one selected from the group consisting of triethylene glycol bis-2-ethylhexanoate (3G8), tetraethylene glycol diheptanoate (4G7), triethylene glycol bis-2-ethylbutyrate (3GH), triethylene glycol bis-2-heptanoate (3G7), dibutoxyethoxyethyl adipate (DBEA), butylcarbitol adipate (DBEEA), dibutyl sebacate (DBS), bis-2-hexyl adipate (DHA), and combinations thereof. In particular, any product from the group consisting of triethylene glycol di-2-ethylbutyrate, triethylene glycol di-2-ethylhexanoate, triethylene glycol di-n-heptanoate, and combinations thereof may be used as the first plasticizer, and in particular, triethylene glycol bis-2-ethylhexanoate (3G8) may be used.

[0080] The adhesive film may also contain an additive as required, which can be selected, for example, from the group of antioxidants, heat stabilizers, UV absorbers, UV stabilizers, IR absorbers, glass adhesion regulators and combinations thereof.

[0081] A hindered antioxidant based on amines or a hindered antioxidant based on phenols can be used. Particularly in the production of polyvinyl butyral (PVB), which requires a processing temperature of 150 °C or higher, an antioxidant based on hindered phenols is especially preferable. The hindered phenol antioxidant could be, for example, IRGANOX 1076, 1010, or similar products, which are available from BASF SE.

[0082] A phosphite-based heat stabilizer can be used as a heat stabilizer, taking into account its compatibility with an antioxidant. The heat stabilizer could be, for example, IRGAFOS 168, which is available from BASF SE.

[0083] In particular, Chemisorb 12, Chemisorb 79, Chemisorb 74, or Chemisorb 102, available from CHEMIPRO KASEI KAISHA, LTD, or Tinuvin 328, Tinuvin 329, or Tinuvin 326, available from BASF SE, can be used as UV absorbers. Tinuvin, available from BASF SE, can be used as a UV stabilizer. ITO, ATO, or AZO can be used as an IR absorber, and a metal salt such as magnesium (Mg), potassium (K), sodium (Na), modified silicon (Si) epoxy oil, or a mixture thereof can be used as a glass adhesion regulator, but this is not the only possible application.

[0084] The film 100 to be bonded can be a multilayer film. The adhesive film 100 can be a laminate with two or more layers. The film can be a laminate with three or more layers, or a laminate with five or more layers. The multilayer film can comprise an adhesive layer 10, 11, which is in direct contact with a translucent laminate such as a glass plate, and a core layer (not shown in the drawing) separate from the adhesive layer. The core layer can have a functional property, e.g., sound insulation, thermal insulation, and the like.

[0085] The multilayer film with an adhesive layer 10, 11 can comprise at least one layer with a polyvinyl acetal resin composition corresponding to the single-layer composition described above. The multilayer film can comprise a polyvinyl acetal resin and a plasticizer. The descriptions of the polyvinyl acetal resin and the plasticizer overlap with the description above, so further description is omitted.

[0086] The adhesive film 100 can contain a soundproofing layer 20. The sound-absorbing layer 20 can be located between the adhesive layers 10 and 11 and can be applied to a surface of the adhesive layer 10.

[0087] The sound-insulating layer 20 may comprise a polyvinyl acetal resin.

[0088] A sound-insulating layer can contain a polyvinyl acetal resin in an amount of 54 to 76 wt.% or 60 to 70 wt.%.

[0089] The sound-insulating layer 20 may contain a plasticizer in an amount of 24 wt.% or more and 46 wt.% or less, or 30 wt.% or more and 40 wt.% or less.

[0090] The polyvinyl acetal resin contained in the soundproofing layer 20 may contain an acetyl group in an amount of 8 wt.% or more, or in an amount of 8 wt.% or more and 30 wt.% or less. A polyvinyl acetal resin contained in the soundproofing layer 20 may contain a hydroxyl group in an amount of 26 wt.% or less, or 5 wt.% or more and 25 wt.% or less. In this case, the foil for bonding 100 can be given a stable sound-insulating property.

[0091] The adhesive film 100 can be produced in film form by extruding a composition containing a resin and a plasticizer with an additive as required, and then forming the composition through a T-nozzle or similar device. If the film to be bonded is a multi-layered film, a laminating agent, such as a feed block, can be attached to the front end of the T-nozzle.

[0092] The adhesive film produced in the form of a foil can be processed into an adhesive film by methods such as thickness control, embossing and the like, but the manufacturing process for an adhesive film is not limited to such a process.

[0093] If the adhesive film 100 simultaneously has the properties of the embossed surface and the properties of the thick area A, the adhesive film 100 has, in addition to the stable surface adhesive property, also a function to prevent double images.

[0094] In particular, if the area A, which increases the thickness, is partially contained within the adhesive film 100, a curved area is created that rapidly changes the surface angle of the adhesive film 100. Bubbles can easily form at this point if the thickening area A is laminated onto a translucent body such as a glass plate. However, the adhesive film of this embodiment is able to provide an adhesive film with excellent optical properties and excellent double-image prevention functionality by controlling bubble formation across the entire adhesive film that includes the curved part.

[0095] Fig.Figure 4 is a conceptual diagram showing an embossing roller used as a comparative example in a film manufacturing process for bonding. Fig. Figure 5 is a conceptual diagram illustrating a method for producing a surface embossing during the manufacture of a film for bonding according to one embodiment. The following section refers to the Fig. 4 to Fig. 5, a method for producing a film for bonding to the embossed surface of the embodiment is described in more detail.

[0096] A single- or multi-layer film 100 is produced in sheet form according to the same procedure as described above, and an embossing roller 500 or a die (not shown) is used to form an embossed surface of the film, and a film for bonding 100 is produced.

[0097] The surface properties of the embossing roller 500 or the die are typically transferred to the surface of the single-layer or multi-layer film by applying a pressing process to the surface of the embossing roller 500 or the die, where the transfer rate can be greater than or equal to 0.6, greater than or equal to 0.7, or less than or equal to 0.99. The transfer rate is evaluated as the surface roughness of a corresponding film surface, assuming the surface roughness of the embossing is 1.

[0098] The surface properties of the embossing roller 500 or the die are usually applied to the surface of the single-layer film or the multi-layer film by applying a process for pressing the surface of the embossing roller 500 or the die, and thus the surface properties of the embossing roller or the die can be controlled to control the properties of the embossed surface of the film.

[0099] The embossing roller 500 or the die can be manufactured by a process such as sandblasting in a concave part of a base roller or a die (applied to Comparative Example 1), as in Fig.4 shown, and by grinding the convex part. At this point, the surface properties can be controlled by adjusting the conditions (particle size, spray pressure, spray distance, spray angle, etc.) applied during the sandblasting treatment and the conditions (degree of grinding) applied during the grinding process, which are complementary to the properties of the embossed surface of the film.

[0100] For example, a sandblasting treatment can be applied 1 to 10 times to the concave part of a base roller with a matte pattern embossing and an Rz roughness of 30 to 90. This treatment applies particles with an average outer diameter of 3 to 8 µm at a distance of 40 to 45 cm using a direct pressure method with a nozzle angle of 85 to 105 degrees and an injection pressure of 0.3 to 0.5 MPa. A fine pattern is formed on the convex part of the film surface to increase the relative volume of the convex part of the film surface compared to the sandblasting of the concave part.

[0101] Furthermore, the convex part of the base roller can be ground, and the grinding thickness can be adjusted from 1 to 10 µm, preferably 3 to 5 µm. Grinding the convex part reduces the voids between the concave parts of the film surface and improves venting stability.

[0102] The grid blasting process and the grinding process can be repeated 1 to 10 times.

[0103] As another example, a grid blasting treatment can be applied 1 to 10 times to the concave part of a base roller with a matte pattern embossing and an Rz roughness of 30 to 90 µm. This treatment uses particles with an average outer diameter of 3 to 8 µm and is applied directly at a pressure of 0.3 to 0.5 MPa from a distance of 15 to 20 cm, with a nozzle angle of 85 to 105 degrees. A fine pattern is then formed on the convex part of the film surface to increase its relative volume compared to the sandblasting of the concave part.

[0104] Furthermore, the convex part of the base roller can be ground, and the grinding thickness can be adjusted from 1 to 10 µm, preferably 3 to 5 µm. Grinding the convex part reduces the voids between the concave parts of the film surface and improves venting stability.

[0105] The grid blasting process and the grinding process can be repeated 1 to 10 times.

[0106] Another example is shot peening, in which particles with a mean outer diameter of 50 µm are applied in a single pass to the surface of a base mold or roller of the mat pattern type, with an Rz roughness of 30 to 90 µm, at a distance of 15 to 20 cm, at a spray pressure of 0.4 MPa and a spray angle of 90°. Additionally, a fine pattern is created on the surface of the film by blasting to adjust the depth distribution of the troughs on the film surface.

[0107] Additionally, the surface of the base form or roller can be sandblasted 1 to 10 times with particles having a mean outer diameter of 5 µm. These particles are applied directly at a distance of 15 to 20 cm with a spray pressure of 5 to 10° and a nozzle angle of 5 to 10 degrees. The adhesive strength of the film to be bonded can be improved by etching any part that protrudes excessively into the surface pattern of the film through the sandblasting process.

[0108] A translucent laminate according to another embodiment disclosed in the present description comprises a first translucent layer; a bonding film arranged on a surface of the first translucent layer; and a second translucent layer arranged on the bonding film.

[0109] The first translucent layer and the second translucent layer can each consist independently of a translucent glass or a translucent plastic.

[0110] The adhesive film used is a film as described above, the detailed description of which overlaps with the description above, so further description is omitted.

[0111] The total number of bubbles counted in three translucent laminates, each 300 mm long and 300 mm wide, can be 5 or less. The detailed description of the measurement conditions and method for counting bubbles in the translucent laminates overlaps with the description below, so it is omitted here.

[0112] The first transmission layer, the second transmission layer, and a combination thereof in the translucent laminate can consist of aged glass.

[0113] With ordinary glass, the edge seal can be reduced because deposits form on the surface depending on temperature and humidity. Specifically, applying aged glass to the translucent layer (the first or second translucent layer) for a specific period at a specific temperature and relative humidity induces scale formation on the surface. This scale is then used in the production of the translucent laminate to test whether the bonding film exhibits excellent edge sealing properties even under challenging conditions.

[0114] Aging can be carried out by storing a glass for 60 days at 25°C and 40% relative humidity.

[0115] A translucent laminate has excellent edge sealing despite the application of aged glass, and it is assumed that improved effects can be achieved by controlling the surface properties of a film for bonding the embodiment.

[0116] A vehicle according to another embodiment disclosed in the present description comprises a translucent laminate as described above. The vehicle comprises a body forming a main body of the vehicle, a drive unit (engine, etc.) attached to the body, a drive wheel rotatably mounted on the body, a connecting piece linking the drive wheel and the drive unit, and a windshield attached to a part of the body, which is a translucent laminate for blocking external wind.

[0117] Detailed examples are described below. In the following descriptions of experiments, where % is mentioned without specifying whether the unit is wt.% or mol.%, it refers to wt.%. Manufacturing example 1: Processing the roller

[0118] A tiny additive pattern was formed on the concave part of a steel roller with an embossed shape that is a matte pattern in which random points are formed, and a grinding treatment was carried out on the convex part of the steel roller.

[0119] As in Fig. As shown in Figure 4, a roller with random irregularities in the form of a matte pattern (Rz = 50 µm) was used as ROLL 0.

[0120] A roller identical to ROLL 0 was treated by blasting in the concave area and by grinding in the convex area, thus producing ROLL 1a, ROLL 1b, and ROLL 1c, respectively. Specifically, the concave part (valley) of the matte pattern was treated by sandblasting, and the concave part (peak) of the matte pattern was treated by grinding. The sandblasting treatment was performed by injecting particles with an average diameter of 5 µm, after they had passed through a 200-mesh filter for impurities, at a distance of 40 to 45 cm and an injection pressure of 0.4 MPa using a direct air jet system. The angle between the roller surface and the injected particles (or a nozzle) was 85 to 105 degrees.

[0121] ROLL 1a was treated once, and ROLL 1b three times, with the blasting and grinding process described above. ROLL 1c was treated ten times with the blasting and grinding process.

[0122] The rollers produced in this way were used in the examples or comparative examples given in Table 1. Production example 1: Production of the film

[0123] The ingredients used in the following examples and comparisons are the same as those listed below.

[0124] Polyvinyl butyral resin (A1): PVA with a degree of polymerization of 1700 and a degree of saponification of 99 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 20.3 wt%, a butyral group of 78.9 wt% and an acetyl group of 0.8 wt%.

[0125] Preparation of the additive: Irganox1076 as an antioxidant at 0.1 wt%, TINUVIN-328 as a UV absorber at 0.2 wt% and Mg acetate as an adhesion promoter at 0.03 wt% were blended and mixed in a tumbler to achieve sufficient dispersion (total amount of 0.33 wt%).

[0126] Examples 1 to 3: Polyvinyl butyral resin (A1) at 72.67 wt%, 3g8 as a plasticizer at 27 wt%, and an additive at 0.33 wt% were added to a twin-screw extruder (a) and processed into a film by a T-die. Subsequently, different rollers (ROLL 1a, ROLL 1b, and ROLL 1c) were used before the film was wound up to perform an embossing treatment. A film onto which a surface pattern was transferred was sampled in the form of a roll sample, thus producing films of Examples 1 to 3. The produced film had a thickness of 760 µm and a width of 1.0 M.

[0127] Comparative Example 1: The foil of Comparative Example 1 was produced under the same conditions as the above Examples 1 to 3, except that it was produced using a roller that was not additively processed for a tiny pattern of the convex part and the concave part (ROLL 0) to perform an embossing treatment. EVALUATION EXAMPLE: PROPERTIES EVALUATION Surface roughness measurement

[0128] The 3D roughness was measured using a measuring device, and the A1 and A2 values ​​were each determined according to ISO 25178. Specifically, the 3D roughness was measured using a BRUKER non-contact optical microscope (model Contour GT) in VSI mode (vertical scanning interferometry).

[0129] Specifically, the 3D roughness values ​​were measured using a 2x eyepiece and a 5x objective lens. During this time, an area with an x-axis length of 0 to 0.887 mm and a y-axis length of 0 to 0.670 mm could be scanned. The measurement was repeated five times by randomly selecting a measurement area from the same pattern, and the three measured values ​​were averaged to obtain a single measurement.

[0130] Sz, A1 (peak area), A2 (valley area) and A2 / A1 values ​​as a result of the measurement are listed in Table 1 below. Edge sealing evaluation

[0131] Preparation of samples for evaluation 1) The samples of the examples and the comparison example were cut into a width*length of 1000*1000 mm and stored for two days at 20 degrees and 20% RH to age. One sample was selected based on the center of the film in the width direction with 300*300 mm, and three samples were cut lengthwise in the same way.

[0132] The samples were pre-laminated between two glass plates with a thickness of 2.1 T (T = mm) and three samples each were produced for the evaluation of each example and comparison example.

[0133] Each sample for evaluation had a width x length of 300 x 300 mm, with one sample having a total length of 1200 mm across four edges. Three samples each were produced for the evaluation of each example and comparison example, and the edge sealing of these was evaluated over a total length of 3.6 m.

[0134] Pre-lamination was carried out by de-aeration with a vacuum ring for 5 minutes at 20 °C and maintenance at three further temperature zones of 70 °C, 85 °C and 100 °C for 15 minutes each.

[0135] Preparation of samples for evaluation 2): A glass plate with a thickness of 2.1 T was cut into a width*length of 300*300 mm and aged for 60 days under conditions of 25 °C and 40% relative humidity. While a sample for evaluation was prepared in the same manner as the samples for evaluation 1), the maintenance temperature after venting was set to 85 °C.

[0136] If a sample exhibited perfect edge sealing and no pattern was discernible, it was awarded 5 points; if a sample exhibited good edge sealing and a pattern only faintly visible to the naked eye, it was awarded 4 points; if a sample exhibited normal edge sealing and a pattern discernible to the naked eye, it was awarded 3 points; if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 2 points; and if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 1 point. The total score for each of the three samples is listed in Table 2. Evaluation of the occurrence of blisters

[0137] The samples for evaluation of the examples and comparison samples were pressed in an autoclave for 20 minutes at 140 °C and 1.2 MPa after pre-lamination, resulting in laminated glass after the main lamination. The time used for the main lamination, consisting of a heating and a cooling period, totaled 90 minutes.

[0138] The number of bubbles present in the laminated glass after the main lamination was determined by the naked eye. If the sum of the bubble counts determined in three samples of each example and comparison example was 5 or less, it was recorded as 5 points; if the sum of the bubble counts was 6 to 10, it was recorded as 3 points; if the sum of the bubble counts was 11 or more, it was recorded as 1 point, and the result was presented in Table 2. [Table 1] Roller used The result of the surface roughness measurement Sz(µm) A1 A2 A2 / A1 Comparison example 1 ROLL 0 50,8 0,3 1,1 3,57 Example 1 ROLL 1a 48,9 0,9 0,3 0,37 Example 2 ROLL 1b 48,6 0,6 0,5 0,82 Example 3 ROLL 1c 48,2 1,2 0,1 0,09 Table 2] Glass type Edge sealing evaluation Evaluation of the occurrence of blisters Pre-lamination temperature Result of the pre-lamination assessment Evaluation of the occurrence of blisters Comparison example 1 Ordinary glass 100°C 15 5 85°C 10 3 70°C 4 1 Aged glass 85°C 5 1 Example 1 Ordinary glass 100°C 15 5 85°C 14 5 70°C 12 5 Aged glass 85°C 13 5 Example 2 Ordinary glass 100°C 14 5 85°C 13 5 70°C 12 5 Aged glass 85°C 13 5 Example 3 Ordinary glass 100°C 15 5 85°C 13 5 70°C 12 5 Aged glass 85°C 12 5

[0139] Referring to Table 1, the Sz values ​​of Examples 1 to 3, in which a tiny pattern is additionally processed by blasting and grinding on the roller surface, showed a maximum difference of 2.6 µm when compared to the Sz value of Comparison Example 1. This indicates that the surface roughness Sz value was not significantly altered despite the additional processing of the tiny pattern on the roller surface. Furthermore, in Examples 1 to 3, an A2 / A1 value of less than 1 was measured, whereas in Comparison Example 1, where no additional processing of minute patterns was performed, an A2 / A1 value of 3.57 was measured, representing a considerably larger difference.

[0140] Referring to Table 2, the cases of the examples achieved a score of 12 or more under all conditions; however, the case of Comparative Example 1 achieved a score of 5 or less on a sample pre-laminated with ordinary glass at 70 °C and on a sample pre-laminated with aged glass at 85 °C, and it could therefore be determined that the edge sealing property of a film was improved when an additional processing of a tiny pattern on the film was carried out.

[0141] In the evaluation of the occurrence of bubbles, the cases of the examples achieved 5 points under all conditions, while the case of the comparison example 1 received a score of 3 or less, with the exception of the case of a sample that was pre-laminated with an ordinary glass at 100 °C, and thus it could be determined that the deaeration stability of the film was improved when additional processing of a tiny pattern on a film was carried out. Manufacturing example 2: Processing the roller

[0142] An additional tiny pattern was formed on the concave part of a steel roller using an embossing die, which is a matte pattern in which random dots were formed, and a grinding treatment was carried out on the convex part.

[0143] A roller (Rz = 50 µm) with irregularities in the form of a matte pattern, as in Fig.The value shown as 4 was used as ROLL 0.

[0144] ROLL 2a, ROLL 2b, and ROLL 2c were each produced by blasting the concave part and grinding the convex part in the same roller as ROLL 0. Specifically, the concave part of the matte pattern was treated by sandblasting, and the convex part of the matte pattern was treated by grinding. The sandblasting treatment was performed by injecting particles that had been filtered through a 200-mesh impurity filter with an average outer diameter of 5 µm, using a direct air jet method at a distance of 15 to 20 cm and an injection pressure of 0.4 MPa. The angle between the roller surface and the injected particles (or a nozzle) was 85 to 105 degrees.

[0145] The ROLL 2a was processed once, the ROLL 2b twice, and the ROLL 2c four times using the blasting and grinding process described above.

[0146] The rollers produced in this way were used in the examples or comparative examples given in Table 1. Production example 2: Production of the film

[0147] The components used in the examples and comparison examples below are the same as those listed below.

[0148] Polyvinyl butyral resin (A1): PVA with a degree of polymerization of 1700 and a degree of saponification of 99 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 20.3 wt%, a butyral group of 78.9 wt% and an acetyl group of 0.8 wt%.

[0149] Preparation of the additive: Irganox1076 as an antioxidant in an amount of 0.1 parts by weight, TINUVIN-328 as a UV absorber in an amount of 0.2 parts by weight and Mg acetate as an adhesion promoter in an amount of 0.03 parts by weight were mixed and blended in a tumbler until sufficiently dispersed (total amount of 0.33 parts by weight).

[0150] Examples 4 to 6: Polyvinyl butyral resin (A1) at 72.67 wt%, 3g8 as plasticizer at 27 wt%, and an additive at 0.33 wt% were added to a twin-screw extruder (a) and produced into a film by a T-die. Subsequently, different roller or transfer conditions were used to perform an embossing treatment as specified in Table 3 below before the film was wound up. A film onto which a surface pattern was transferred was sampled in the form of a roll sample, producing films of Examples 4 to 6. The pressure condition described above was used as the transfer condition, but the temperature condition was applied as specified in Table 3. The film produced had a thickness of 760 µm and a width of 1.0 M.

[0151] Comparative Example 2: The foil of Comparative Example 2 was produced under the same conditions as the above Example 4, except that it was produced using a roller that was not additively processed for a tiny pattern of the convex part and the concave part (ROLL 0) to perform an embossing treatment. Evaluation example 2: Assessment of properties - Measurement of surface roughness

[0152] The 3D roughness was measured using a measuring device, and the Mr1 and Mr2 values ​​were each determined according to ISO 25178. Specifically, the 3D roughness was measured using a non-contact optical microscope from BRUKER (model Contour GT) in VSI mode (vertical scanning interferometry).

[0153] Specifically, the 3D roughness values ​​were measured using a 2x eyepiece and a 5x objective lens. During this time, an area with an x-axis length of 0 to 0.887 mm and a y-axis length of 0 to 0.670 mm could be scanned. The measurement was repeated five times by randomly selecting a measurement area from the same pattern, and the three measured values ​​were averaged to obtain a single measurement.

[0154] The values ​​calculated from the measurement results for Sz, Mr1, Mr2, rev_Mr2 and Mr-rev_Mr2 are listed in the following Table 3. Edge sealing evaluation

[0155] Preparation of samples for evaluation 1) The samples of the examples and the comparison example were cut into a width*length of 1000*1000 mm and stored for two days at 20 degrees and 20% relative humidity to age. One sample was selected based on the center of the film in the width direction with 300*300 mm, and three samples were cut lengthwise in the same way.

[0156] The samples were placed between two glass plates with a thickness of 2.1 T (T=mm, as below) to be pre-laminated, and three samples each were produced for evaluation of each example and comparison example.

[0157] Each sample for evaluation had a width x length of 300 x 300 mm, with one sample having a total length of 1200 mm across four edges. Three samples each were produced for the evaluation of each example and comparison example, and the edge sealing of these was evaluated over a total length of 3.6 m.

[0158] Pre-lamination was carried out by de-aeration with a vacuum ring for 5 minutes at 20 °C and maintenance at three further temperature zones of 70 °C, 85 °C and 100 °C for 15 minutes each.

[0159] Preparation of samples for evaluation 2): A glass plate with a thickness of 2.1 T was cut into a width*length of 300*300 mm and aged for 60 days under conditions of 25 °C and 40% relative humidity. While a sample for evaluation was prepared in the same manner as the samples for evaluation 1), the maintenance temperature after venting was set to 85 °C.

[0160] If a sample exhibited perfect edge sealing and no pattern was discernible, it was awarded 5 points; if a sample exhibited good edge sealing and a pattern only faintly visible to the naked eye, it was awarded 4 points; if a sample exhibited normal edge sealing and a pattern discernible to the naked eye, it was awarded 3 points; if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 2 points; and if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 1 point. The total score for each of the three samples is listed in Table 4. Evaluation of the occurrence of blisters

[0161] The samples for evaluation of the examples and comparison samples were pressed in an autoclave for 20 minutes at 140 °C and 1.2 MPa after pre-lamination, resulting in laminated glass after the main lamination. The time used for the main lamination, consisting of a heating and a cooling period, totaled 90 minutes.

[0162] The number of bubbles present in the laminated glass after the main lamination was determined by the naked eye. If the sum of the bubble counts determined in three samples of each example and comparison example was 5 or less, it was recorded as 5 points; if the sum of the bubble counts was 6 to 10, it was recorded as 3 points; if the sum of the bubble counts was 11 or more, it was recorded as 1 point, and the result was presented in Table 4. Table 3 Transfer condition The result of the 3D roughness measurement Roller used Transmission temperature (°C) Sz(um) Mr1(%) Mr2(%) Rev_Mr2(%) Mr1-rev_Mr2(%) Comparative example 2 ROLL 0 115 59 9,8 88,9 11,1 -1,3 Example 4 ROLL 2a 115 57 13,1 89,9 10,1 3,0 Example 5 ROLL 2b 115 55 13,2 93,2 6,8 6,4 Example 6 ROLL 2c 115 54 14,6 98,0 2,0 12,6 Table 4] Glass type Edge sealing evaluation Evaluation of the occurrence of blisters Pre-lamination temperature Result of the pre-lamination assessment Evaluation of the occurrence of blisters Comparison example 2 Ordinary glass 100°C 15 5 85°C 9 3 70°C 5 1 Aged glass 85°C 5 1 Example 4 Ordinary glass 100°C 14 5 85°C 13 5 70°C 12 5 Aged glass 85°C 12 5 Example 5 Ordinary glass 100°C 15 5 85°C 14 5 70°C 12 5 Aged glass 85°C 12 5 Example 6 Ordinary glass 100°C 15 5 85°C 15 5 70°C 13 5 Aged glass 85°C 13 5

[0163] Referring to Table 3, the Sz values ​​of examples 4 to 6, in which a tiny pattern is additionally processed by blasting and grinding on the roller surface, had a difference of a maximum of 5 µm compared to the Sz value of comparison example 2, and it could therefore be determined that the value of the surface roughness Sz was not significantly changed, even though a tiny pattern was additionally processed on the roller surface.

[0164] Furthermore, in examples 4 to 6, a Mr1-rev_Mr2 value greater than 3.0 was measured, whereas in comparison example 2, where a tiny pattern was not additionally processed, the Mr1-rev_Mr2 value was -1.3. By additionally processing a tiny pattern on the roller surface, the density distribution of the protruding valleys in the valley section of the surface of the produced film could be relatively reduced, and the value of the peak valley distribution increased. In this case, the edge sealing demonstrated during pre-lamination could be further improved.

[0165] Table 4 shows that when evaluating edge sealing, the cases of Examples 4 to 6 achieved a score of 12 or more under all conditions, but the case of Comparative Example 2 achieved a score of 5 or less on a sample pre-laminated with ordinary glass at 70 °C and on a sample pre-laminated with aged glass at 85 °C, and thus it could be concluded that the edge sealing property of a film was improved when an additional processing of a tiny pattern was carried out on the film.

[0166] In the evaluation of the occurrence of bubbles, the cases of examples 4 to 6 achieved 5 points under all conditions, while the case of comparison example 2 received a score of 3 or less, with the exception of the case of a sample that was pre-laminated with ordinary glass at 100 °C, and thus it could be determined that the de-venting stability of the film was improved when an additional processing of a tiny pattern on the film was carried out.

[0167] It was also found that when using aging lenses with a comparatively uneven surface, examples 4 to 6 showed a better result compared to example 2. Manufacturing example 3: Processing the mold

[0168] An additional tiny pattern was formed on the surface of a steel mold using an embossing die, which is a matte pattern in which random dots were formed.

[0169] A mold (Rz = 50 µm) with irregularities in the form of a matte pattern was used as MOLD 0.

[0170] MOLD 1 was produced by shot blasting and sandblasting, using the same roller as ROLL 0. Specifically, shot blasting was performed by injecting particles filtered through a 140-mesh impurity filter with an average outer diameter of 5 µm, using a direct air jet method at a distance of 15 to 20 cm and an injection pressure of 0.4 MPa. The angle between a matte pattern surface and the injected particles (or a nozzle) was 90°. Sandblasting was performed by injecting particles filtered through a 200-mesh impurity filter with an average outer diameter of 5 µm, using a direct air jet method at a distance of 15 to 20 cm and an injection pressure of 0.4 MPa.The angle between the surface of a matte pattern and the injected particles (or a nozzle) was 5 to 10°.

[0171] The mold produced in this way was used for the examples listed in Table 5. Production example 3: Production of the film

[0172] The ingredients used in the following examples and comparisons are the same as those listed below.

[0173] Polyvinyl butyral resin (A1): PVA with a degree of polymerization of 1700 and a degree of saponification of 99 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 20.3 wt%, a butyral group of 78.9 wt% and an acetyl group of 0.8 wt%.

[0174] Preparation of the additive: Irganox1076 as an antioxidant in an amount of 0.1 parts by weight, TINUVIN-328 as a UV absorber in an amount of 0.2 parts by weight and Mg acetate as an adhesion promoter in an amount of 0.03 parts by weight were mixed and blended in a tumbler until sufficiently dispersed (total amount of 0.33 parts by weight). Production of plates

[0175] Production of plate 1: The polyvinyl butyral resin (A) with 72.67 wt.%, 3g8 as plasticizer with 27 wt.% and an additive with 0.33 wt.% were fed to a twin screw extruder and processed with a T-nozzle to form a plate 1 with a uniform surface.

[0176] Production of plate 2: In the production process using the same method as for plate 1, die lip cooling at 15 °C was used during film production by extrusion, and a plate 2 was obtained in which a melt fracture formed on the surface. Pattern transfer to the plates

[0177] Example 7: A pattern was transferred to the surface of the manufactured plate 1 using MOLD 1.

[0178] Example 8: A pattern was transferred to the surface of the manufactured plate 2 using MOLD 1.

[0179] Comparative example 3: A pattern was transferred to the surface of the manufactured plate 1 using MOLD 0.

[0180] Comparative example 4: The manufactured plate 2 was used without transferring a pattern. Evaluation example 3: Assessment of properties - Measurement of surface roughness

[0181] The 3D roughness was measured using a measuring device, and the values ​​Svk, S*vk, A2, and Sz were each determined according to ISO 25178. Specifically, the 3D roughness was measured using a non-contact optical microscope from BRUKER (model Contour GT) in VSI mode (vertical scanning interferometry).

[0182] Specifically, the 3D roughness values ​​were measured using a 2x eyepiece and a 5x objective lens. During this time, an area with an x-axis length of 0 to 0.887 mm and a y-axis length of 0 to 0.670 mm could be scanned. The measurement was repeated five times by randomly selecting a measurement area from the same pattern, and the three measured values ​​were averaged to obtain a single measurement.

[0183] The values ​​calculated from the measurement results for Svk, S*vk, A2 and Sz are listed in Table 5 below. Edge sealing evaluation

[0184] Preparation of samples for evaluation 1) The foils of the examples and the comparison examples were cut to a width*length of 1000*1000 mm and aged for two days at 20 degrees and 20 rh% (relative humidity %). One sample was selected based on the center of the foil in the width direction with 300*300 mm, and three samples were cut lengthwise in the same way.

[0185] The samples were placed between two glass plates with a thickness of 2.1 T (T=mm, as below) to be pre-laminated, and three samples each were produced for evaluation of each example and comparison example.

[0186] Each sample for evaluation had a width x length of 300 x 300 mm, with one sample having a total length of 1200 mm across four edges. Three samples each were produced for the evaluation of each example and comparison example, and the edge sealing of these was evaluated over a total length of 3.6 m.

[0187] Pre-lamination was carried out by de-aeration with a vacuum ring for 5 minutes at 20 °C and maintenance at three further temperature zones of 70 °C, 85 °C and 100 °C for 15 minutes each.

[0188] If a sample exhibited perfect edge sealing and no pattern was discernible, it was awarded 5 points; if a sample exhibited good edge sealing and a pattern only faintly visible to the naked eye, it was awarded 4 points; if a sample exhibited normal edge sealing and a pattern discernible to the naked eye, it was awarded 3 points; if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 2 points; and if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 1 point. The total score for each of the three samples is listed in Table 6. Evaluation of the occurrence of blisters

[0189] The samples for evaluation of the examples and comparison samples were pressed in an autoclave for 20 minutes at 140 °C and 1.2 MPa after pre-lamination, resulting in laminated glass after the main lamination. The time used for the main lamination, consisting of a heating and a cooling period, totaled 90 minutes.

[0190] The number of bubbles present in the laminated glass after the main lamination was determined by the naked eye. If the sum of the bubble counts determined in three samples of each example and comparison example was 5 or less, it was recorded as 5 points; if the sum of the bubble counts was 6 to 10, it was recorded as 3 points; if the sum of the bubble counts was 11 or more, it was recorded as 1 point, and the result is shown in Table 6 below. Assessment of the occurrence of bubbles in a high temperature and high humidity environment

[0191] The samples for the evaluation of the examples and the comparison examples were left in an environment of 85 °C and 92% relative humidity for 120 hours after pre-lamination, and the evaluation of bubble occurrence was carried out in the same manner as the bubble occurrence evaluation described above. The evaluation of the individual examples and comparison examples is shown in Table 6. Table 5] Used plate Form used The result of the 3D roughness measurement Svk(um) S*vk(um) DSvk(um) DSvk / Svk DSvk / Svk A2 Sz(um) Example 7 Plate 1 MOLD1 5,4 7,0 1,6 0,30 0,03 0,18 63,3 Example 8 Plate 2 MOLD1 7,0 10,7 3,7 0,53 0,06 0,25 63,7 Comparison example 3 Plate 1 MOLD0 3,6 9,7 6,1 1,68 0,09 0,15 64,1 Comparison example 4 Plate 2 - 2,5 15,9 13,4 5,35 0,21 0,06 64,0 Table 6] Edge sealing evaluation Evaluation of the occurrence of blisters Pre-lamination temperature (°C) Result of the pre-lamination assessment Evaluation of the occurrence of blisters Assessment of the occurrence of blisters in a high temperature and high humidity environment Example 7 100 15 5 5 70 15 5 3 Example 8 100 15 5 5 70 13 5 5 Comparison example 3 100 15 5 5 70 12 5 3 Comparison example 4 100 15 5 5 70 12 5 3

[0192] In Table 5, DSvk values ​​of less than 4 were measured for examples 7 and 8, while the DSvk values ​​of the comparison examples 3 and 4 were above 6.

[0193] The DSvk / Svk values ​​of examples 7 and 8 were measured in the range of 0.30 to 0.60, while the DSvk / Svk values ​​of comparison examples 3 and 4 were greater than 1.6.

[0194] The DSvk / Sz values ​​of examples 7 and 8 were measured at 0.06 or less, while the DSvk / Sz values ​​of comparison examples 3 and 4 were measured at 0.09 or more.

[0195] The A2 values ​​of examples 7 and 8 were measured at 0.18 or more, while the A2 values ​​of comparison examples 3 and 4 were measured at 0.15 or less.

[0196] The Sz values ​​of the examples and comparison examples were measured in the range of 63 to 64.5. This shows that the Sz value is not significantly changed despite the additional processing of a tiny pattern.

[0197] Table 6 shows that, in the edge sealing assessment, the examples achieved a score of 13 or higher under all conditions, while the comparative examples 3 and 4 only achieved a score of 12 when pre-laminated at a temperature of 70 °C. This indicates that the adhesive film with a DSvk value of 6 µm or less exhibits excellent edge sealing, even when treated with a low-temperature lamination process.

[0198] For the assessment of the occurrence of bubbles, the evaluation results of the examples and comparison examples generally proved to be excellent, and in particular example 8 achieved a rating of 5 points, despite being exposed to an environment with permanently high temperature and high humidity as well as a normal environment. Manufacturing example 4: Processing the roller

[0199] An additional tiny pattern was formed on a concave part of a steel roller using an embossing die, which is a matte pattern in which random dots were formed, and a grinding treatment was carried out on the convex part.

[0200] A roller (Rz = 50 µm) with irregularities in the form of a matte pattern, as in Fig. The value shown as 4 was used as ROLL 0.

[0201] ROLL 4a, ROLL 4b, and ROLL 4c were each produced by blasting the concave part and grinding the convex part in the same roller as ROLL 0. Specifically, the concave part of the matte pattern was treated by sandblasting, and the convex part of the matte pattern was treated by grinding. The sandblasting treatment was performed by injecting particles that had been filtered through a 200-mesh impurity filter with an average outer diameter of 5 µm, using a direct air jet method at a distance of 40 to 45 cm and an injection pressure of 0.4 MPa. The angle between a matte pattern surface and the injected particles (or a nozzle) was set to 85° to 105°.

[0202] The ROLL 4a was processed once with the above-mentioned blasting and grinding treatment, the ROLL 4b was processed three times with the above-mentioned blasting and grinding treatment, and the ROLL 4c was processed ten times with the above-mentioned blasting and grinding treatment.

[0203] The rollers produced in this way were used in the examples or comparative examples given in Table 1. Production example 4: Production of the film

[0204] The ingredients used in the following examples and comparisons are the same as those listed below.

[0205] Polyvinyl butyral resin (A2): PVA with a degree of polymerization of 1700 and a degree of saponification of 99 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 19.6 wt%, a butyral group of 80.0 wt% and an acetyl group of 0.4 wt%.

[0206] Polyvinyl butyral resin (B): PVA with a degree of polymerization of 2400 and a degree of saponification of 88 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 8.6 wt%, a butyral group of 79.9 wt% and an acetyl group of 11.5 wt%.

[0207] Preparation of the additive: Irganox1076 as an antioxidant in an amount of 0.1 parts by weight, TINUVIN-328 as a UV absorber in an amount of 0.2 parts by weight and Mg acetate as an adhesion promoter in an amount of 0.03 parts by weight were mixed and blended in a tumbler until sufficiently dispersed (total amount of 0.33 parts by weight).

[0208] Examples 9 to 11: Polyvinyl butyral resin (A2) at 72.67 wt%, 3g8 as a plasticizer at 27 wt%, and an additive at 0.33 wt% were fed into a twin-screw extruder (a), and polyvinyl butyral resin (B) and 3g8 as a plasticizer at 35 wt% were fed into another twin-screw extruder (b) for co-extrusion. The above-mentioned compositions were formed by a feed block into a shape of (A2) composition / (B) composition / (A2) composition, and subsequently, a film in the shape, where the thickness of one end is greater than the thickness of the other end, was produced by a T-nozzle.Before the film was wound up, different rollers (ROLL 4a, ROLL 4b and ROLL 4c) were applied to the upper and lower parts, respectively. A separate embossing treatment then shaped a film, onto which a surface pattern had been transferred, into the form of a roller pattern to produce films of Examples 9 to 11. During this process, to facilitate the transfer of the surface pattern from a film, the angle of both sides of an embossing roller was set to 0.014° and the transfer was carried out.

[0209] Comparative example 5: A foil of comparative example 1 was produced in the same way as the above examples 1 to 3, except for the embossing treatment with a roller, in which the additional processing of a tiny pattern on the convex and the concave part was not carried out (ROLL 0). Evaluation example 4: Assessment of properties Measurement of the wedge angle

[0210] The film sample to be evaluated has a thickness-increasing area corresponding to the entire film; therefore, the thicknesses of both ends were measured and used as Ha and Hb values. The thicknesses of both ends were measured using the Mitsutoyo 547-401 thickness gauge.

[0211] After measuring the length of a width connecting both ends of the foil sample to be evaluated, the measured Ha value, Hb value and w value were inserted into equation 3 below and the measured value of the wedge angle was determined. θ=arctan(Hb−Haw)

[0212] In equation 3, Hb is the thickness of a thicker side between the two ends of the thickness enlargement region, Ha is the thickness of a thinner side between the two ends of the thickness enlargement region, and w is the length of a width connecting the two ends of the thickness enlargement region. Measurement of surface roughness

[0213] The 3D roughness was measured using a measuring device, and the A1 and A2 values ​​were each determined according to ISO 25178. The 3D roughness was measured using a BRUKER non-contact optical microscope (model Contour GT) in VSI (Vertical Scanning Interferometry) mode.

[0214] Specifically, the 3D roughness values ​​were measured using a 2x eyepiece and a 5x objective lens. During this time, an area with an x-axis length of 0 to 0.887 mm and a y-axis length of 0 to 0.670 mm could be scanned. The measurement was repeated five times by randomly selecting a measurement area from the same pattern, and the three measured values ​​were averaged to obtain a single measurement.

[0215] Sz, A1 (peak area), A2 (valley area) and A2 / A1 values ​​as a result of the measurement are listed in Table 7 below. Edge sealing evaluation

[0216] Preparation of samples for evaluation 1) The foils of the examples and the comparison examples were cut to a width*length of 1000*1000 mm and aged for two days at 20 degrees and 20 rh% (relative humidity %). One sample was selected based on the center of the foil in the width direction with 900*300 mm, and three samples were cut lengthwise in the same way.

[0217] The samples were pre-laminated between two glass plates with a thickness of 2.1 T (T = mm) and three samples each were produced for the evaluation of each example and comparison example.

[0218] Each sample for evaluation had a width x length of 900 x 300 mm, with one sample having a total length of 2400 mm across four edges. Three samples each were prepared for the evaluation of each example and the comparison example, and the edge sealing of these was evaluated over a total area of ​​7.2 m.

[0219] Pre-lamination was carried out by de-aeration with a vacuum ring for 5 minutes at 20 °C and maintenance at three further temperature zones of 70 °C, 85 °C and 100 °C for 15 minutes each.

[0220] Preparation of samples for evaluation 2): A glass plate with a thickness of 2.1 T was cut into a width*length of 900*300 mm and aged for 60 days under conditions of 25 °C and 40% relative humidity. While one sample for evaluation was prepared in the same manner as the samples for evaluation 1), the maintenance temperature after venting was set to 85 °C.

[0221] If a sample exhibited perfect edge sealing and no pattern was discernible, it was awarded 5 points; if a sample exhibited good edge sealing and a pattern only faintly visible to the naked eye, it was awarded 4 points; if a sample exhibited normal edge sealing and a pattern discernible to the naked eye, it was awarded 3 points; if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 2 points; and if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 1 point. The total score for each of the three samples is listed in Table 8. Evaluation of the occurrence of blisters

[0222] The samples for evaluation of the examples and comparison samples were pressed in an autoclave for 20 minutes at 140 °C and 1.2 MPa after pre-lamination, resulting in laminated glass after the main lamination. The time used for the main lamination, consisting of a heating and a cooling period, totaled 90 minutes.

[0223] The number of bubbles present in the laminated glass after the primary lamination was determined by visual inspection. If the sum of the bubble counts in three samples of each example and comparison example was 5 or less, it was awarded 5 points; if the sum of the bubble counts was 6 to 10, it was awarded 4 points; if the sum of the bubble counts was 11 to 15, it was awarded 3 points; if the sum of the bubble counts was 16 or more, it was awarded 1 point, and the results are shown in Table 8 below. [Table 7] Roller used Wedge angle (°) The result of the surface roughness measurement Sz(µm) A1 A2 A2 / A1 Comparison example 5 ROLL 0 0,014 50,8 0,226 0,63 2,79 Example 9 ROLL 4a 0,014 48,9 0,70 0,34 0,49 Example 10 ROLL 4b 0,014 48,6 0,86 0,29 0,34 Example 11 ROLL 4c 0,014 48,2 1,46 0,09 0,06 Table 8] Glass type Edge sealing evaluation Evaluation of the occurrence of blisters Pre-lamination temperature Result of the pre-lamination assessment Evaluation of the occurrence of blisters Comparison example 5 Ordinary glass 100°C 14 5 85°C 8 3 70°C 4 1 Aged glass 85°C 4 1 Example 9 Ordinary glass 100°C 14 5 85°C 13 4 70°C 12 4 Aged glass 85°C 12 4 Example 10 Ordinary glass 100°C 14 5 85°C 12 4 70°C 10 3 Aged glass 85°C 12 3 Example 11 Ordinary glass 100°C 15 5 85°C 13 5 70°C 12 4 Aged glass 85°C 12 4

[0224] Referring to Table 7 and Table 8, the wedge angle of each foil sample was assessed as the same value of 0.014° for the evaluation of each example and comparison example in all cases.

[0225] The Sz values ​​of Examples 9 to 11, in which additional processing of a tiny pattern was carried out by blasting and grinding, had a maximum difference of 2.6 µm compared to the Sz value of Comparison Example 5. This showed that, although additional processing of a tiny pattern was performed on the roller surface, the surface roughness Sz value was not significantly altered. On the other hand, in Examples 9 to 11, where additional processing of a tiny pattern was performed, an A2 / A1 value of less than 1 was measured, but in Comparison Example 5, an A2 / A1 value of 2.79 was measured, indicating a comparatively large difference.

[0226] Referring to Table 8, in the evaluation of edge sealing, a score of 10 or more was achieved under all conditions in the case of Examples 9 to 11, but a score of 8 or less was achieved in the case of the comparative Example 5 for samples pre-laminated with ordinary glass at 85 °C and 70 °C, and for a sample pre-laminated with aged glass at 85 °C, and thus it can be concluded that the edge sealing property of a film is improved when an additional processing of a tiny pattern is carried out on the film.

[0227] In assessing the occurrence of bubbles, the cases of examples 9 to 11 achieved a score of 3 or more under all conditions, but the case of comparison example 5 only achieved 1 point when pre-laminated with ordinary glass at 70 °C and with aged glass at 85 °C, and thus it can be concluded that the de-venting stability of a film is improved when the film is additionally treated with a tiny pattern. Manufacturing example 5: Processing the roller

[0228] An additional tiny pattern was formed on a concave part of a steel roller using an embossing die, which is a matte pattern in which random dots were formed, and a grinding treatment was carried out on a convex part.

[0229] A roller (Rz = 50 µm) with irregularities in the form of a matte pattern, as in Fig. The value shown as 4 was used as ROLL 0.

[0230] ROLL 5a, ROLL 5b, and ROLL 5c were each produced by blasting the concave part and grinding the convex part in the same roller as ROLL 0. Specifically, the concave part of the matte pattern was treated by sandblasting, and the convex part of the matte pattern was treated by grinding. The sandblasting treatment was performed by injecting particles that had been filtered through a 200-mesh impurity filter with an average outer diameter of 5 µm, using a direct air jet method at a distance of 40 to 45 cm and an injection pressure of 0.4 MPa. The angle between a matte pattern surface and the injected particles (or a nozzle) was set to 85° to 105°.

[0231] The ROLL 5a was treated once with the above-mentioned blasting and grinding treatment, the ROLL 5b was treated twice with the above-mentioned blasting and grinding treatment, and the ROLL 5c was treated four times with the above-mentioned blasting and grinding treatment.

[0232] The rollers produced in this way were used in the examples or comparative examples given in Table 9. Production example 5: Production of the film

[0233] The ingredients used in the following examples and comparisons are the same as those listed below.

[0234] Polyvinyl butyral resin (A1): PVA with a degree of polymerization of 1700 and a degree of saponification of 99 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 20.3 wt%, a butyral group of 78.9 wt% and an acetyl group of 0.8 wt%.

[0235] Polyvinyl butyral resin (B): PVA with a degree of polymerization of 2400 and a degree of saponification of 88 and n-BAL were added to carry out an ordinary synthesis procedure, thereby obtaining a polyvinyl butyral resin with a hydroxyl group of 8.6 wt%, a butyral group of 79.9 wt% and an acetyl group of 11.5 wt%.

[0236] Preparation of the additive: Irganox1076 as an antioxidant in an amount of 0.1 parts by weight, TINUVIN-328 as a UV absorber in an amount of 0.2 parts by weight and Mg acetate as an adhesion promoter in an amount of 0.03 parts by weight were mixed and blended in a tumbler until sufficiently dispersed (total amount of 0.33 parts by weight).

[0237] Examples 12 to 14: Polyvinyl butyral resin (A1) at a wt% concentration of 72.67%, 3g8 as a plasticizer at a wt% concentration of 27%, and an additive at a wt% concentration of 0.33% were fed into a twin-screw extruder (a), and polyvinyl butyral resin (B) at a wt% concentration of 65%, and 3g8 as a plasticizer at a wt% concentration of 35%, were fed into another twin-screw extruder (b) for co-extrusion. Subsequently, the above-mentioned compositions were formed by a feed block into a shape of (A1)-composition / (B)-composition / (A1)-composition and produced by a T-die into a film with a thickness at one end greater than the thickness at the other end.Before the film was wound up, different rollers (ROLL 6a, ROLL 6b, and ROLL 6c, as shown in Table 9) were applied to the upper and lower parts, respectively. A separate embossing process then scanned a film, onto which a surface pattern had been transferred, in the form of a roller pattern to produce films of Examples 9 to 11. During this process, to facilitate the transfer of the surface pattern from one film, the angle of both sides of an embossing roller was set to 0.014°, and the transfer was carried out. The resulting film had a thickness of 960 µm at one end, a thickness of 1200 µm at the other end, and a width of 1.0 M.

[0238] Comparative example 6: A foil of comparative example 1 was produced in the same way as the above examples 1 to 3, except for the embossing treatment with a roller, in which the additional processing of a tiny pattern on the convex and the concave part was not carried out (ROLL 0). Evaluation example 5: Assessment of properties Measurement of the wedge angle

[0239] The film sample to be evaluated has a thickness-increasing area corresponding to the entire film; therefore, the thicknesses of both ends were measured and used as Ha and Hb values. The thicknesses of both ends were measured using the Mitsutoyo 547-401 thickness gauge.

[0240] After measuring the length of a width connecting both ends of the foil sample to be evaluated, the measured Ha value, Hb value and w value were inserted into equation 3 below and the measured value of the wedge angle was determined. θ=arctan(Hb−Haw)

[0241] In equation 3, Hb is the thickness of a thicker side between the two ends of the thickness enlargement region, Ha is the thickness of a thinner side between the two ends of the thickness enlargement region, and w is the length of a width connecting the two ends of the thickness enlargement region. Measurement of surface roughness

[0242] The 3D roughness was measured using a measuring device, and the Mr1 and Mr2 values ​​were each determined according to ISO 25178. The 3D roughness was measured using a BRUKER non-contact optical microscope (model Contour GT) in VSI (Vertical Scanning Interferometry) mode.

[0243] Specifically, the 3D roughness values ​​were measured using a 2x eyepiece and a 5x objective lens. During this time, an area with an x-axis length of 0 to 0.887 mm and a y-axis length of 0 to 0.670 mm could be scanned. The measurement was repeated five times by randomly selecting a measurement area from the same pattern, and the three measured values ​​were averaged to obtain a single measurement.

[0244] The values ​​for Sz, Mr1, Mr2, rev_Mr2 and Spv as a result of the measurement are listed in Table 9 below. Edge sealing evaluation

[0245] Preparation of samples for evaluation 1) The foils of the examples and the comparison examples were cut to a width*length of 1000*1000 mm and aged for two days at 20 degrees and 20 rh% (relative humidity %). One sample was selected based on the center of the foil in the width direction with 900*300 mm, and three samples were cut lengthwise in the same way.

[0246] The samples were pre-laminated between two glass plates with a thickness of 2.1 T (T = mm) and three samples each were produced for the evaluation of each example and comparison example.

[0247] Each sample for evaluation had a width x length of 900 x 300 mm, with one sample having a total length of 2400 mm across four edges. Three samples each were prepared for the evaluation of each example and the comparison example, and the edge sealing of these was evaluated over a total area of ​​7.2 m.

[0248] Pre-lamination was carried out by de-aeration with a vacuum ring for 5 minutes at 20 °C and maintenance at three further temperature zones of 70 °C, 85 °C and 100 °C for 15 minutes each.

[0249] Preparation of samples for evaluation 2): A glass plate with a thickness of 2.1 T was cut to a width x length of 900 x 300 mm and left to be treated with aging for 60 days under conditions of 30 °C and 50% rh. While a sample for evaluation was prepared in the same way as the samples for evaluation 1), the maintenance temperature after venting was set to 85 °C.

[0250] If a sample exhibited perfect edge sealing and no pattern was discernible, it was awarded 5 points; if a sample exhibited good edge sealing and a pattern only faintly visible to the naked eye, it was awarded 4 points; if a sample exhibited normal edge sealing and a pattern discernible to the naked eye, it was awarded 3 points; if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 2 points; and if a sample exhibited poor edge sealing and a pattern discernible to the naked eye, it was awarded 1 point. The total score for each of the three samples is listed in Table 10. Evaluation of the occurrence of blisters

[0251] The samples for evaluation of the examples and comparison samples were pressed in an autoclave for 20 minutes at 140 °C and 1.2 MPa after pre-lamination, resulting in laminated glass after the main lamination. The time used for the main lamination, consisting of a heating and a cooling period, totaled 90 minutes.

[0252] The number of bubbles present in the laminated glass after the primary lamination was determined by visual inspection. If the sum of the bubble counts determined in three samples of each example and comparison example was 5 or less, it was awarded 5 points; if the sum of the bubble counts was 6 to 10, it was awarded 4 points; if the sum of the bubble counts was 11 to 15, it was awarded 3 points; if the sum of the bubble counts was 16 or more, it was awarded 1 point, and the results are shown in Table 10 below. Table 9] Roller used Transmission temperature (°C) Wedge angle 1 (°) The result of the 3D roughness measurement Sz(µm) Mr1(%) Mr2(%) Rev_Mr2(%) Spv(%) Comparative example 6 ROLL 0 115 0,014 64,4 8,2 91,1 8,9 -0,7 Example 12 ROLL 6a 115 0,014 61,6 9,0 92,0 8,0 1,0 Example 13 ROLL 6b 115 0,014 60,1 15,5 92,8 7,2 8,3 Example 14 ROLL 6c 115 0,014 59,0 21,3 91,7 8,3 12,9 Table 10] Glass type Edge sealing evaluation Evaluation of the occurrence of blisters Pre-lamination temperature Result of the pre-lamination assessment Evaluation of the occurrence of blisters Comparison example 6 Ordinary glass 100°C 14 5 85°C 8 3 70°C 5 1 Aged glass 85°C 5 1 Example 12 Ordinary glass 100°C 14 5 85°C 12 5 70°C 11 4 Aged glass 85°C 11 4 Example 13 Ordinary glass 100°C 15 5 85°C 14 5 70°C 12 4 Aged glass 85°C 12 5 Example 14 Ordinary glass 100°C 15 5 85°C 15 5 70°C 13 5 Aged glass 85°C 13 5

[0253] Referring to Table 9, the wedge angle of each foil sample of each example and comparison example was rated as 0.014°.

[0254] The Sz values ​​of examples 1 to 3, in which additional processing of a tiny pattern is carried out by blasting and grinding, had a maximum difference of 5.4 µm compared to the Sz value of comparison example 5, and it could therefore be determined that, although additional processing of a tiny pattern was carried out on the roller surface, the value of the surface roughness Sz was not greatly changed.

[0255] Furthermore, in the cases of Examples 12 to 14, where additional processing of a tiny pattern was performed, Spv values ​​in the range of 1.0 or higher were observed, and the Spv values ​​increased in the order of Examples 12, 13, and 14. However, in the case of the comparative Example 6, where additional processing of a tiny pattern was performed, an Spv value of less than 0 was measured. From the above, it can be concluded that when additional processing of a tiny pattern was performed on the roller surface, the density distribution of the protruding valley in the valley section of the surface of the produced film could be relatively reduced, and the Spv value could be increased. Similarly, when the number of additional processing operations of a tiny pattern was increased, the Spv values ​​were also increased.

[0256] Table 10 shows that, in the evaluation of edge sealing, the cases of Examples 12 to 14 achieved a score of 11 or more under all conditions, whereas the case of Comparative Example 6 achieved a score of less than 10 under all conditions, except when pre-laminated with ordinary glass at 100 °C, and in particular when pre-laminated with ordinary glass at a pre-lamination temperature of 70 °C, the score was only 5 points. It is known from the above that an adhesive film with an Spv value of 0% or more exhibits stable edge sealing characteristics and, in particular, excellent edge sealing characteristics when pre-laminated at a low temperature.

[0257] Furthermore, the cases in Examples received 4 points or more under all conditions; however, the case in Comparative Example 6 received a score of 3 or less, except for a sample pre-laminated with ordinary glass at 100 °C, and in particular, when pre-laminated with ordinary glass at 70 °C, the score was only 1 point. From the above, it is known that the deaeration stability of the film is improved by additional processing of a tiny pattern on the film for bonding, and that the film, especially when pre-laminated at a low temperature, can exhibit excellent deaeration properties.

[0258] In examples 12 to 14, where aged glass was used, the pre-lamination was rated at 11 or more points and the bubble occurrence at 4 or more points, whereas in comparative example 6, the pre-lamination was rated at only 5 points and the bubble occurrence at only 1 point. This clearly demonstrates that when laminating aged glass, whose surface is not flat, laminating with an adhesive film, where an additional processing of a tiny pattern is carried out, enables stable edge sealing and de-airing performance.

[0259] Although the exemplary embodiments have been described in detail, the scope of the present invention is not limited to these, and modifications and changes made by those skilled in the art using the basic concept of the present invention as defined in the following claims are within the scope of protection of the present invention. (DESCRIPTION OF REFERENCE MARKS) 100 sheets of adhesive film 500, 500' Embossed roller 10, 11 Adhesive layer 20 Sound-insulating layer A area with increasing thickness

Claims

[1] Adhesive film comprising: an embossed surface, wherein the embossed surface has an A2 / A1 value of 1 or less; and a region of increasing thickness, wherein the region of increasing thickness has a first end and a second end, and the thickness of the first end differs from the thickness of the second end; where a wedge angle (θ) is calculated according to equation 1 below and the wedge angle of the region with increasing thickness is 0.01 to 0.04°, where the embossed surface has an Sz value of 30 to 90 µm, where the ratio of Ha to w is between 0.0002 and 0.0015, and where the A2 value is 0.6 or less, θ=arctan(Hb−Haw) where in equation 1 Hb is a thickness of the thicker end from the first end to the second end of the region with increasing thickness, Ha is a thickness of the thinner end from the first end to the second end of the region with increasing thickness, and w is the width from the first end to the second end of the region with increasing thickness. [2] The film for bonding according to claim 1, wherein the embossed surface has an Sz value of 45 to 75 µm. [3] The film for bonding according to claim 1, wherein the Al value is 0.5 or more. [4] The adhesive film according to claim 1, wherein the A2 value is 0.5 or less. [5] The film for bonding according to claim 1, which is a single-layer film or a composite film with two or more layers, and comprises a polyvinyl acetal resin. [6] Adhesive film, comprising: an embossed surface with a regular or irregular pattern, where the embossed surface has a Mr1 value and a Mr2 value, where a rev_Mr2 value is a value resulting from subtracting the Mr2 value from 100%, and where the embossed surface has a Mr1 value that is equal to or greater than the rev_Mr2 value, and where the A2 value is 0.6 or less. [7] The film for bonding according to claim 6, where a peak-valley distribution value is calculated according to equation 1 below and the embossed surface has a peak-valley distribution value of 0% to 25%, Spv=Mr1−rev_Mr2 where in equation 1 Spv is the peak-trough distribution value and the rev_Mr2 value is a value that results from subtracting the Mr2 value from 100%. [8] The adhesive film according to claim 6, wherein the Mr1 value is 10% or more.

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