ISO 57-1975 PDF

Full title and description

ISO 57:1975 — Bleached lac — Specification. Specifies forms, types and quality requirements for bleached lac (white/bleached lac), and defines required test methods and acceptance criteria for physical and chemical properties used in trade and quality control of lac products.

Abstract

This international standard gives definitions, material forms, classification of types (regular, refined), and detailed requirements for bleached lac including limits for volatile matter (moisture), matter insoluble in hot alcohol, colour, wax, ash, rosin and copals, matter soluble in water, chlorine content, acid value and mineral acid, free chlorine or peroxides, and heavy metals (arsenic, lead). It also includes test methods and annexes describing laboratory procedures for the key determinations and a requirements table for purchaser/vendor agreement.

General information

• Status: Withdrawn / cancelled.
• Publication date: 1975-02 (first edition).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 87.060.20 — Binders (lac, shellac and related resins).
• Edition / version: Edition 1 (1975); amendment ISO 57:1975/Amd 1:1996 exists (also withdrawn).
• Number of pages: 24 (main text).

Key bibliographic and lifecycle facts: ISO lists the standard as withdrawn; national catalogues record the withdrawal effective in 2000 and note the 1996 amendment.

Scope

Applies to bleached lac intended for industrial use and trade. The standard defines acceptable physical and chemical properties of bleached lac (both bone-dry and surfacedry forms), sampling and testing procedures to verify compliance, and classification into types (for example regular and refined) with specific numerical limits for parameters such as moisture, insoluble matter, water-soluble matter and permitted impurities. It is intended for supply, inspection and contractual specification between vendor and purchaser.

Key topics and requirements

• Definitions and product forms (appearance and presentation).
• Limits for volatile matter (moisture) — specified for bone-dry and surface-dry lac.
• Limits for matter insoluble in hot alcohol and matter soluble in water (different limits for regular and refined types).
• Requirements for colour, wax, ash, and absence of rosin and copals.
• Controls for chlorine content, acid value and mineral acid, free chlorine/peroxides, and heavy metals (arsenic, lead) where specified by purchaser.
• Annexed test methods (volatilization, hot-alcohol solubility, colour comparison, etc.) and a requirements table for contractual use.

Typical use and users

Used by manufacturers, refiners and traders of lac and shellac-type resins, quality control and analytical laboratories, procurement/specification engineers in paints, varnishes and adhesives industries, and regulatory or standards bodies when referencing historical product requirements. It served as a contractual specification between purchasers and vendors for bleaching and trading lac.

Related standards

Standards in the same ICS group and topic include specifications for seedlac and shellac (for example ISO 55, ISO 56-series) and other ISO/TC 50 outputs covering lac and similar natural resins. The 1975 standard was amended by ISO 57:1975/Amd 1:1996 (amendment to the same number) — both items are recorded as withdrawn in ISO’s catalogue.

Keywords

bleached lac; lac; shellac; bleached shellac; specification; trade quality; test methods; volatile matter; hot-alcohol solubility; colour comparison; arsenic; lead; ISO/TC 50; binders (ICS 87.060.20).

FAQ

Q: What is this standard?

A: ISO 57:1975 is an international specification that defined quality, chemical and physical requirements and test methods for bleached lac (white bleached lac) used in trade and manufacturing.

Q: What does it cover?

A: It covers definitions, product form and types, limits for moisture, insoluble matter, colour, wax, ash, rosin/copals, water-soluble matter, chlorine content, acid value/mineral acid, free chlorine/peroxides, certain heavy metals, plus annexed laboratory methods and a requirements table for purchaser/vendor agreements.

Q: Who typically uses it?

A: Producers and refiners of lac products, QC and analytical laboratories, buyers and specifications teams in paints, varnishes and adhesives sectors, and standards or procurement groups referencing historical product specifications.

Q: Is it current or superseded?

A: The standard is withdrawn (cancelled) in ISO records; an amendment (ISO 57:1975/Amd 1:1996) was issued but the item and amendment are recorded as withdrawn. National catalogues indicate withdrawal actions (for example withdrawal recorded from 13 April 2000). Users should consult current national or ISO catalogues or more recent standards for up-to-date requirements.

Q: Is it part of a series?

A: It belongs to ISO/TC 50 work on lac and related resins and is associated with other ISO specifications for seedlac and shellac (ISO 55, ISO 56-series). It was issued as a standalone specification with a later amendment.

Q: What are the key keywords?

A: Bleached lac, lac, shellac, bleached shellac, specification, test methods, volatile matter, insoluble in hot alcohol, colour, binders, ISO 57:1975.