GB/T Translated English of Chinese Standard: GB/T NATIONAL STANDARD OF THE

Transcription

1 Translated English of Chinese Standard: GB/T GB NATIONAL STANDARD OF THE PEOPLE S REPUBLIC OF CHINA ICS Y 89 GB/T Replacing GB/T Spectacle frames General requirements and test methods 眼镜架通用要求和试验方法 (ISO 12870:1997, Ophthalmic optics - Spectacle frames - General requirements and test methods, MOD) Issued on: December 11, 2003 Implemented on: June 1, 2004 Issued by: General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China Page 1 of 21

2 Table of Contents Foreword Scope Normative references Terms and definitions Product classification Requirements Sampling Pretreatment and conditions Sample state, test procedure and determination rules Test methods Marking Page 2 of 21

3 Foreword This Standard modifies and adopts ISO 12870:1997 Ophthalmic optics - Spectacle frames - General requirements and test methods (in English). The technical differences between this Standard and ISO 12870:1997 are: - DELETE the subclause 4.9 Resistance to optical radiation in ISO 12870:1997; - ADD the subclausese 5.4 Appearance quality, Tensile properties and Coating adhesion (which are required in the original GB/T ); - The sample placement device in 7.1 Test lens, 8.4 Determination rules and 9.7 Resistance to perspiration and Table 3 Marking in adopt the corresponding contents in ISO/DIS 12870:2002 (E). This Standard is the revision to GB/T Spectacle frames. It retains only 3 items of the original standard from the content and layout. In order to facilitate the use, this Standard has the following editorial modifications: - DELETE the foreword of ISO 12870:1997; ADD the foreword of this Standard; - The contents of the standard listed in the clause Normative references of ISO 12870:1997 are directly referenced in this Standard; - COMBINE Table 1 and Table 2 in 4.1 of ISO 12870:1997 INTO Table 1 of this Standard; - REPLACE the words this International Standard WITH this Standard. This Standard replaces GB/T Spectacle frames. This Standard is proposed by China Light Industry Association. This Standard is under the jurisdiction of Sub-Technical Committee on Ophthalmic Optical of National Technical Committee on Optical and Optical Instrument of Standardization Administration of China. Drafting organizations of this Standard: Donghua University, China National Inspection & Testing Centre For Ophthalmic Optic Glass and Enamel Products, Taiheng Glasses City (Group) Co., Ltd., Jiangsu East Optics Co., Ltd., Shanghai Nojiri Glasses Co., Ltd. Main drafters of this Standard: Zhang Nini, Tang Lingling, Zhou Junwen, Lu Shoucheng, Zhang Jingdong, Zhuo Keming. The previous edition of the standard replaced by this Standard is as follows: GB/T Page 3 of 21

4 Spectacle frames General requirements and test methods 1 Scope This Standard specifies the product classification, requirements, test methods and marks of spectacle frames. This Standard applies to all types of spectacle frame made of metal, plastic and natural organic materials. This Standard does not apply to spectacle frames designed for special eye protection. 2 Normative references The following standards contain provisions which, through reference in this Standard, constitute provisions of this Standard. For dated reference, subsequent amendments to (excluding corrections to), or revisions of, any of these publications do not apply. However, the parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards. For undated references, the latest edition of the normative document referred to applies. GB/T 196 General purpose screw threads - Basic dimensions for diameter from 1 to 600 mm 3 Terms and definitions The following terms and definitions apply to this Standard. 3.1 metal frame Spectacle frame with the main part of the front frame being made of metal materials. 3.2 plastic frame Spectacle frame with the main part of the front frame being made of plastic (or similar) Page 5 of 21

5 materials. 3.3 natural organic materials Material that has not been synthesized from other raw organic materials and, when processed, remains essentially in its original state. Note 1: The word process is defined as cutting, shaping, bending, polishing and heating. Note 2: Some natural organic materials, such as shellfish, wood materials. 3.4 spectacle frames model Spectacle frame produced to a common design, using the same materials (but not necessarily the same pigmentation) and surface treatment. 3.5 horizontal boxed lens size Distance a between the two vertical edges of the frame around the lens (see Figure 1). 3.6 distance between lenses Distance d between the two lenses (see Figure 1). 3.7 distance between centres Distance c between the centre C of the box (see Figure 1). 3.8 overall length of side Distance l between the centre line of side and the intersection point of side end at the thread axis (see Figure 2). Page 6 of 21

6 c) light finger pressure to open and close the sides; d) the sides do not close under its own weight at any point in the opening/closing cycle. Note: d) does not apply to the sides fitted with sprung joints. 5.8 Coating performance Coating adhesion After being tested in accordance with 9.6, the sample surface shall be no wrinkle, defects and peeling Resistance to perspiration When tested in accordance with 9.7, and under the identification condition specified in 8.3, after 8 h of the test, visually inspect each part of the specimen; after 24 h of the test, visually inspect the part that easily contacts with the skin of users for long term (inner side of the side and lower edge of the rim); the specimen shall meet the following requirements at each test: a) no corrosion point or discoloration; b) no rust, erosion or peeling off the coating. 5.9 Resistance to ignition When tested in accordance with 9.8, there shall be no continued combustion on the tested position after withdrawal of the test rod. 6 Sampling In order to adapt to the test requirements, randomly select at least 3 samples for each type of spectacle frame, identified as Sample 1, Sample 2 and Sample 3, and then pretreated according to Clause 7. Note: For this Standard, if the spectacle frame design, material or surface treatment has changed, then the spectacle frame model is changed. 7 Pretreatment and conditions 7.1 Test lens Before the test, the spectacle frame shall be fitted with the test lens which shall satisfy: glass lens or resin lens with a vertex of 0.00 D ± 25 D, a centre thickness of 2.00 mm Page 10 of 21

7 9.2 Dimensional stability at elevated temperature Apparatus Oven: the temperature is adjustable within the room temperature ~ +60 C, the temperature fluctuation within the oven is 3 C Flat plate: glass or metal materials, mounted in the oven either on, or parallel to, the base of the chamber Linear measuring device: measuring accuracy is at least 0.5 mm Procedure In the environment in accordance with 7.2, TAKE the spectacle frame with test lenses fitted and with the sides open to the fullest extent; MEASURE the distance between the side tips using the measuring device meeting the requirement of RECORD this measurement value as the pre-heating dimension L Before the test, STABILIZE the oven at the test temperature, PLACE the test sample on the plate, with the sides still open to the fullest extent, and with the top edge of the front and the top edge of the sides resting on the plate surface. PLACE the sample on the plate in the oven, and ensure that the sample does not touch other samples or the oven wall When the test sample has reached the test temperature of 55 C ± 5 C, leave it for 2 h min After the above test, REMOVE the test sample, still on the plate, from the oven; STABILIZE for a period of at least 2 h at the environment complying with 7.2; and then according to the method for measuring L 0, MEASURE the distance between the side tips; RECORD this measurement value as the post-heating dimension L 1, and calculate the difference L 1 L Tensile properties Apparatus Tensile testing machine with a accuracy of not less than 1% Procedure Metal frame: CLAMP two sides with the clamp at a distance of 20 mm from the dowelscrew centre, MOVE at the opposite direction; when reaching the required value, REMOVE the spectacle frame to observe the damage. Plastic frame and natural organic material frame: FIX the front rim within a distance of Page 13 of 21

8 9.4.2 Procedure MOUNT test sample on the device with the sides extended and with the front downwards; CLAMP the sample within 2 mm of the boxed centre of one lens. Lower the pressure peg so that it rests on the back surface of the unclamped lens within 2 mm of its boxed centre, ensuring that there is no movement of the lens. RECORD this value as the starting position. Then move the pressure peg downwards slowly and smoothly with a force of not more than 5 N; INCREASE the force until the distance equal to (10 ± 1) % of the boxed centre distance; RETAIN the initial displacement for 5 s RETURN the pressure peg to its starting position. After a relaxation period of 20 s, lower the pressure peg again until it just rests on the lens. RECORD this value as the end point If the maximum force of 5 N is insufficient to displace the pressure peg over the distance required, record the displacement at this moment, and retain the force for 5 s. REPEAT the procedure of Calculate the displacement between the end point and the starting point of the pressure peg. CALCULATE the percentage deformation using formula (1), and check if there is fracture on the spectacle frame. 100 where Φ - the percentage deformation; x - the displacement of the pressure peg, in millimeters (mm); c - the boxed centre distance, in millimeters (mm). 9.5 Endurance Apparatus The test apparatus consists of two clamping devices mounted on universal joints and a bridge support. The bridge support is a rigid metal reed with a diameter of 10 mm ± 1 mm and with a thickness of 1 mm ± 0.5 mm; the positions of the clamps and bridge support, relative to each other, are adjustable by at least 40 mm horizontally and vertically. The apparatus is capable of continuously and smoothly imparting a cyclical motion to Page 15 of 21

9 After the cycles have been completed, remove the sample from the apparatus. Measure the distance d 2 between the sides at the measuring point; the difference between d 1 and d 2 does is permanent deformation INSPECT the spectacle frame for fractures, cracks or change in side movement; RECORD the permanent deformation. 9.6 Coating adhesion BEND the sides to 120 ± 20, so that the convex arc radius is 15 mm; OBSERVE the surface condition of the sample. 9.7 Resistance to perspiration Apparatus Oven: capable of controlling the test temperature of 55 C ± 5 C Glass cylinder container: the diameter is 220 mm ± 20 mm, the height is 100 mm ± 10 mm; can be covered Volumetric flask: 1 L Water: ph = 5.0 ~ 7.5 (25 C), the conductivity is 0.50 ms/m (25 C) Artificial sweat solution, comprising: a) lactic acid: ρ = 1.21 g/ml, purity > 85%; b) sodium chloride: analytical reagent purity; c) water: meeting the requirements of WEIGH 50 g ± 0.1 g of lactic acid and 100 g ± 0.1 g of sodium chloride; DISSOLVE in water; USE the volumetric flask as described in to make 1 L of solution Frame supports, of glass or inert plastic, fitted in the container so that the sample(s) are held above the artificial sweat solution Procedure Pour the artificial sweat solution into the container to a depth of 10 mm, so that the lowest part of the frame shall be just 15 mm ± 3 mm above the solution. (see Figure 6). Page 18 of 21