Intangible assets net (Details) - ZHEJIANG TIANLAN - CNY (¥) ¥ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Patents	¥ 3,750	¥ 3,750
Others	165	165
Intangible assets, gross	3,915	3,915
Less: accumulated amortization	(2,050)	(1,795)
Intangible assets, net	¥ 1,865	¥ 2,120

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Name Accounting Standards Codification
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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Gross carrying amount before accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights.

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Amount before accumulated amortization of finite-lived intangible assets classified as other.

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