Orla Kiely, the brand known for its 1970s-inspired prints and favoured by the Duchess of Cambridge and Alexa Chung, has closed its stores and website in the UK and Ireland after its parent company, Kiely Rowan, appointed administrators to wind down the company.

The company, named after the Irish designer who owns it – known as the “queen of prints” – and her husband, Dermott Rowan, said it was entering voluntary liquidation “following various challenges that have faced the company over the past few years, both in the UK and abroad”.

Insolvency practitioners David Rubin & Partners have been appointed to handle the winding down of the handbag and fashion business, which includes stores on King’s Road and Seven Dials in London and one in Kildare, Ireland.

A spokesman said the insolvency process, under which all assets of the business are sold to pay off creditors, had just commenced and the company would not be placed into liquidation until the beginning of October.

Facebook Twitter Pinterest Classic Orla Kiely patterns, from Orla Kiely: A Life in Pattern at the Fashion and Textiles Museum. Photograph: Orla Kiely

It is understood that about 40 of the group’s 50-plus staff, half of whom work in the stores and the rest at the brand’s head office in Fitzrovia in London, have been made redundant.

A spokesman added: “Orla Kiely’s home and design licensing business will not be affected, and its selection of accessories and homewares will continue to be sold through its distribution partners.”

In the year to March 2017, Kiely Rowan made sales of £8.3m, up 15% on a year before, as the brand expanded in the US and far east but pre-tax profits fell by about a third to £101,000 as interest payments on its debts jumped to £221,597 from just under £82,000 a year before. The group’s bank overdraft more than tripled to £1.9m.

Julie Palmer, a partner at the advisory firm Begbies Traynor, said: “Orla Kiely had the backing of high-profile celebrities and clearly had appeal to the latest generation of shoppers. If this latest news shows anything, it’s that there is no magic formula to success. Celebrity endorsements and being on trend don’t always guarantee results.

“Businesses must remain vigilant, adapt and innovate with a core strength if they are to rise out this distressing time for retail.”

The problems at Orla Kiely come amid widespread difficulties on the high street that have pushed well-known retailers including House of Fraser and Toys R Us into administration. A whole string of retailers, including New Look and Mothercare, have embarked on mass store closures as they cope with the switch to online shopping and a slowdown in consumer spending.

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Kiely, who set up her own label 23 years ago after cutting her teeth as a wallpaper and fabric designer, was this year celebrated in A Life in Pattern, an exhibition at the Fashion and Textile Museum in London. Her breakthrough came in the mid-1990s with her signature laminated bags that featured a simplified plant print in bright and bold colours.

In recent years the brand has become ubiquitous as its simple colourful graphics have played into the trend for mid-century furnishings. The label’s designs, once the preserve of well-heeled arty types, have appeared on bicycles, bedding, Tesco bags for life, budget fashion at the Uniqlo chain and on yoghurts.

The homeware business, which accounts for about half the brand’s sales, will not be affected by the liquidation of Kiely Rowan.